The Truth About Flat Tappet Cam Failure

[@TxStang]

I worked in quality control at a manufacturer though not for a cam company for 7 years before my stroke and I can tell you how it works . In a batch of less than 100 parts you inspected just 1 part , In a batch of 100 parts or more the inspection rate was 10 % so we grabbed 10 random parts none next to each other and did a full inspection as per blueprints . If we found no issues at all the whole batch passed as per the company inspection quidelines , if even 1 failed inspection out of the 10 then that triggered a full batch inspection and any that did not pass were culled out . I personally never had any batch of parts that fully passed and days were long culling the bad parts and tagging them and locking them up in the " cage " ( a fenced area only accessable by inspectors and management ) Imagine spendaing a day inspecting 1000 parts and culling out 200 to 300 of them . Parts in there were supposed to be destroyed and either scraped or recycled in house but some supervisors and managers would re inspect and sign off on them and send them to the floor anyways to keep their numbers up and stats high . I would imagine these cam comanies have the same issues with many parts sneaking by that should be rejected .

[@chestrockwell8328]

Your take sounds logical. All across the board of products from every category quality is down. Lately the blame has been some bug that gave people the sniffles; however I think it is what you described Craig. Management on up want numbers and dollars and they'll put the consumer last.

[@lowluv72]

This is exactly how it works, different industries, different tooling but management will come by and sign off on out of spec pieces and ship them. Then the workers miss out on bonuses and numbers because management undermined them. This is exactly correct.

[@trillrifaxegrindor4411]

inspection frequencies vary as do levels of acceptability according to ISO and qs9000 quality requirements and the requirements of the specific part...........ive been a machinist and inspect ,program and verify the quality of my own parts and those of others..........batches of 100 absolutely have a higher inspection frequency than 1 in 100.......it would be more like 1 in 10 or whatever the statistical control of the part required according to process capability

[@dantupper1784]

Doing QA work you often 'deal' with Management undermining your work. The destroyed Space Shuttles and their Crews were killed by Management ignoring the people that knew their sh*t.

[@scottvining3117]

Sounds just like a pharmaceutical company's I worked at. Pack that shit up and send it out.

[@robertheymann5906]

As a machinist my thoughts on flat tappet failure have generally assumed exactly that, the manufacturer's all using roller tappets have moved away from taking the time to get the convex surface of flat tappets correct and or the taper required on lobes. Quality control indeed

[@b.c4066]

and the good high quality oem flat tappet lifters are gone. better off having a 45 year old set resurfaced than buying the crap being sold today.

[@Anarchy-Is-Liberty]

​@@b.c4066 Not true! You can still buy Johnson Hylift lifters! Also, there are a couple of family owned cam companies who make their own cams and lifters, and take a lot of pride in their products. I no longer buy anything from any "corporate conglomerate", because they're only in it for the money, and could give a damn about the end users. Comp Cams, Lunati, Edelbrock, TCI, Fast, Russel, and many others, are all now owned by one massive corporation named Industrial Opportunity Partners!! Holley has done the same thing, now owns over 70 companies!!! Please explain, how in the hell are you going to provide a good product, when it's all about the bottom line and your share holders? All I've got to say about that is... Hell no!!!

[@travisbooth7106]

I started measuring lifters after having several failures and it took several sets to get a good set and compared new cams with nos cam and new cams quality was horrible that combined with insanely aggressive cam lobes trying to out due each other at same time zink removed from oil

[@Haffschlappe]

China sucks

[@corbinhbucknerjr558]

Glad I saw this video. I've built three engines in my life, 2 Pontiac 400's, and one flathead Ford. Both Pontiacs were before 2000, and the flathead was in 2003. No problems with any of them. Now I've got one more, it will be my first Chevy engine, a 350 for my 81 Corvette. I wanted to put a flat tappet, since that older tech is what I know and understand. Now, I have to go with your advice and adapt my block for a roller cam. I can't be rebuilding twice, and I am not building a horsepower monster, I just want reliability above all, with some mild power upgrades. But you convinced me, I need to go roller and update my knowledge. Thanks for the advice.

[@mrpmotorsports8536]

Thank you for your time and sharing these videos with everyone! It’s much appreciated! With everything else out here you see you can always guarantee one thing.. you always offer great knowledgeable advice and information! Thanks for your time and dedication 😎👊

[@slick-px4pq]

Thank you, very good info. The man who owns my preferred machine shop told me the QC issues extend to roller lifters as well. They had to change their methods and get their people trained as to what to look for when inspecting lifters before assembling an engine. He said 10-12% of lifters are rejected and go back to the supplier. Also, he recommends saving the lifters when tearing down an engine as they just might be the best lifters available.

[@flinch622]

That makes sense: a manufacturer with quality control issues is likely to have them across the board. What did he share about roller lifter inspections?

[@704406bbl]

That is the best explanation I ever heard and makes sense. Back in my earlier years the first engine I built was a 440 and used a mopar purple shaft hydraulic flat tappet and worked great then a few sbc cam swaps no problems. Now with all the problems now I'll be using roller for sure in my 440s. . Low buck builds are not what they used to be but rather spend the money and let that motor run and live. A testament to this is my two chevy pick ups have rollers from the factory and one has 235k miles and the other 198k miles and still run great. Thank you for sharing your findings and experience.

[@frigglebiscuit7484]

ive got a lunati cam and howard lifters in my 400 mopar. runs great.

[@dougsmaintenanceshop5868]

This is the video every car guy needs to watch. I had gleaned from reading old forum posts that non-detergent, SAE 30 oil + ZDDP additive was the way to go. Then, I read that it is possible to add TOO MUCH ZDDP. THIS clears the air. Thank you. I think it is roller for me all the way now. Period.

[@davechat-yu3du]

Thank you. You are correct in your reasoning. I changed a Ford FE cam last year. I am an old machinist. The first cam I bought was a Melling OE type replacement. I checked it out and found no taper on 2 lobes. The next cam custom ground from a grinder in California and this was bent .015 at the center journal. There replacement seamed correct except for their hydraulic lifers, I disassembled all 16 and found one had a broken spring inside, but all were extremally dirty inside and out. The cam has lived so far but has a lifter tick when fully warmed up. The quality control on everthing seems to have vanished. Good luck to all and check every thing you buy!!

[@mikestrasheim923]

I just found your channel, I watched your LS1 build , very good thank you. I recently took a Pontiac 400 to a machine shop that I had never been to before and he told me exactly what you say in this video, just not as detailed. He could not stress enough to not use flat tappet cams. I have used flat tappet cams forever, and yes I've had some fail but no other machine shops or anyone for that matter claimed it was the motor oil, just poor manufacturing. So with that in mind I thought this new machinist was just blowing smoke. So thanks for making this a qualified issue , I appreciate it. I really like how you present information, I will be watching you frequently I'm sure.

[@jimhailmann7052]

100% RIGHT, BEEN BUILDING ENGINES FOR 60 YEARS. I BUILD ENGINES FOR CIRCLE TRACK THAT DO NOT ALLOW ROLLER CAMS. AS FAR AS FLAT TAPPETS GO I HAVE FOUND EVERY THING YOU SAID TO BE 100% CORRECT. GOOD VIDEO

[@lesteredwards2576]

Nailed it. I'm retired now and don't usually comment but have gone thru everything you described. Would not warranty spec engines that had to have flat tappet cam and turned others away that would not upgrade to a roller. Did you know that in the 1970's Chevy dealers replaced many V8 cams under warranty? I don't know of any that got torn apart and cleaned.

[@shaggydogg630]

Yup, 305 and 350’s if I remember right. Did many cam replacements.

[@Oscarphone]

If I am not mistaken it was the late 70s and early 80s. The problem was that GM switched to laser hardening of the cams and the hardening didn't penetrate deep enough.

[@misters2837]

@@Oscarphone For some reason pre-85/86 Chevy 305's seemed to be the most troublesome....At least I remember putting many new cams in those....Even though I specialized in Ford Engines myself...The dealers were so busy they had our shop doing them!

[@InPrimer]

Best video on the interwebs on this topic! You have challenged some of my assumptions on the topic (soft steel) but done so with actual data. There are a lot of engines still in service (my beloved Chevy Stovebolt among them) for which no roller cam option exists. So we are left pouring over oil spec sheets, looking for NOS parts, or just squinting and hoping that our cams survive. But for those working with more modern/ common stuff….I totally agree that going roller is the only way to go. One little addendum/ correction on the diesel oil front. There are many diesel oils which still contain pretty high levels of ZDDP. But one cannot simply assume that they do. Gotta do your homework, and then even if you do pick a high ZDDP oil, I don’t think it guarantees a modern flat tappet cam will live. Lake Speed Jr has a good video on this topic. Too much other weirdness with metallurgy, lobe taper, etc.

[@gj91471]

Just use Oil Extreme Concentrate in your engine oil.

[@leonardgilbreath9004]

I've been watching you for a while and the information you put out and the advice you give on engine's and what to or how to do engine rebuild is greatly appreciated and you answer questions on what to do and how to do it is one I respect, keep telling us on how to do it thumbs up 👍

[@Myvintageiron7512]

Thanks

[@whocares2227]

Great information and advice. I am 100% with you, budget for a roller cam into your build. I have been building engines successfully for 45 years and like you have had virtually no valvetrain problems in the early days. You could build an engine, drive it 10 miles with varying rpm and load and it was broke in, basically a stomp and go engine. My most recent engine is an early 454BBC, first cam Isky flat tappet, then a Crower flat tappet, now another rebuild with all new and better $$$$ parts and a Comp Cams roller kit, No troubles. After watching your video, maybe the flat tappet cams went out from double springs or detergent oil but they didn't last very long after the break in. My advice is the same, don't go cheap on your valvetrain put in a roller and if you have any doubts, make a call to the cam manufacturer to verify that all of your parts will work together.

[@TargaWheels]

Wow your reasoning and explanation is the best I've heard. The last engine I built was in 2001, and I never had a cam failure back then. Never did a over-2000 rpm break-in back then. All these cam failures happened after I was done building. So all what you're saying kind of lines up with what I've seen.

[@milomanx6531]

I wish you made this video two years ago when I went through the "Flat Tappet" nightmares. Lost two cams with metal chips in all the parts of the engine, with damage to the crank, roller rockers and oil pump, etc. Now it's only roller cams for me. I also, have been doing this for years and never had a problem before. The EPA screwed me big time.

[@wintonhudelson2252]

I've been involved with hi-perf engines for over 50 years. Your findings are spot on. I'm refreshing an original '70 LTI 350 after the new year. It will receive a roller cam and lifters. Thank you for your commentary.

[@Myvintageiron7512]

Thanks for sharing

[@shanescrimshire8395]

@@Myvintageiron7512 so what to do if I'm building an engine that rollers aren't available for? I'm currently building a 4.0 jeep engine. Have the cam and lifters on hand.

[@dougsmaintenanceshop5868]

@@shanescrimshire8395 I'd trust myvintageiron's response to your question, of course, but thought I'd offer a couple ideas: 1) send the cam out to reputable cam grinder or company, someone like Delta Camshaft in Tacoma, Washington. He has a KZbin channel. Have him check the cam and lifters and verify they are dimensionally correct. 2) myvintage iron has a pretty excellent hydraulic cam install video. Maybe with these 2 ideas, and a true-blue break-in oil, you could go forward with confidence.

[@richardprice5978]

@@shanescrimshire8395 give up swap-time, on the 4.0 my family's fully loaded TJ 2006 has eaten 3x engine's ( 800lb vs LSX 6.2L @ 400lb ish and pass epa/CARB testing and double the potential power and its cheaper ect ) all OEM spec ( 150-ish on the dashboard odometer and as far as i know using real jeep parts from the dealership aka not aftermarket engine parts and yes flat tapped cam X3 wiped out ) and used royal purple aka new hight quality oil the ZDP isn't there and or now made for it and it's also married to automatic aka junk-combo separately in the right era's there okay independently but married junk, right now-2022 N-5 exhaust lifter or lobe is bad i can here it and it's locked up the engine under the right condition's luckily i so far have been able to restart it hand baring and a hammer ect, the older 4.0L jeep blocks have access plate for the cam and lifter's area's so copycat it ( or find a useable pre1962 ish block sorry can't remember the parts numbers/year that's ideal ) and use tie bar's if you're still insistent or that dummy desperate ( MR.boomer stubborn hasn't given in yet others wise it would already have been swaped out lsx or coyote 5.0L and 6 or 10speed automatic or a diesel engine swap ), still going to use 383-B/906-used in RB's as conversion tie-bar and your going to need to get/find a custom grind camshaft for the tie's to work and not wipe out my charger's1966-71 383-B engine died in 2019-21 as well a roller would have made rebuilding and salvage easier as it was sabotaged parked overnight in my driveway but the camshaft and lifter's are now boat anker's now aka junk and un-regrind-able

[@richardprice5978]

@@Myvintageiron7512 thanks for pointing out the feeling's of a 1/2 sticky cam/lobe after the "break in period is over"/damaged engine ( how to get if free-er when driving rather than being helpless ) it's saved me from stalling in traffic a couple of times as now i just try and keep it at 2200RPM's like it's a generator engine even know the ( i borrowed ) 4.0L is really power band/max torque and MPG wise better at 650-1700RPM and max-horsepower is at 3k ish and fuel-pig

[@frankadkins3861]

Thank you for making this video! Just so you know, I have been a fan of Tony DeFeo (Uncle Tony's Garage) since his magazine days many decades ago. He released a video in which he references you and this video, and he encourages his viewers to check you out. So, here I am. Having said all of that, I was a dealership "wrench" for most of my life. I have also been teaching automotive technology for over 20 years, and I have built dozens of engines for myself and my customers over the last 40 years. Knock on wood, I have not suffered a cam failure. I ALWAYS do the proper break-in procedure. I didn't know about the problem with detergents in modern oils, so thank you for that. Also, thank you for checking the Rockwell hardness of cams and lifters. Like many others, I assumed the Chinese metal was soft. I know that the cam lobes require rake and the lifter faces require radius. I could see the radius with a straight edge, but I never knew how much rake was necessary. So, again, thank you for that information. I'll admit, over the last four years or so, I have built four engines for myself. In one engine I used an old cam and lifter package (brand new parts that I'd had on the shelf since the '90s) and in the other three engines I reused low mileage cams and lifters (lifters reinstalled on their respective lobes) because I was terrified to purchase new cam/lifter packages. None of the cams are perfectly matched for how the engines are used, but at least I didn't have to build the engines two or three times.

[@DeanBishop-gb9mx]

Have followed you for some time now and appreciate your message. Have a new rebuilt 350 ready for break in. I am tearing it back down and going with a roller. Thanks for looking out for us.😊

[@6h471]

1 thing I always found interesting. Back in the early '80's I worked for a Toyota dealership. At that time the old 2T engines. which was a solid lifter pushrod engine, was still in production. If you disassembled the engine and looked at the lifters, you would find that none of the lifters ever rotated, with a clearly seen silver stripe in the center of the lifter face, and varnished areas on each side of the face. Never saw a cam failure in those, and nothing was built into the engine to prevent them from rotating. They simply ran centered on the cam load with a flat faced lifter. Makes me wonder why most engines are designed with radiused lifters, offset from the cam lobes.

[@scottrobertson6949]

The offset is to prompt rotation, the radius is so the lifter doesn't dig into running surface, like a ball rolling on a surface verses a flat disc. The way the 2T probably got away with it was very low spring loads and hard lifters and lobes and back then the oil wasn't as cleaned up for EPA. The lifter is designed to roll over the lobe not the lobe wipe under the lifter. Like someone said flat tappet cams years ago were not as aggressive and had less open pressure on them. Hi-intensity, Hi-velocity profiles with higher rocker ratios are high risk. The hi-volume budget cams from the then two US manufactures don't really have enough tapper only .0015 when it really needs to be .003. when it is all said and done Flat tappet is like playing Russian roulette....VERY STRESSFUL!!!

[@6h471]

@@scottrobertson6949 I still say it's unnecessary and undesirable to have a radiused lifter running on a tapered lobe. If all you want to do is induce the lifter to rotate, that can be accomplished with all surfaces flat and parallel simply by offsetting the lifters from the lobes. The contact area between the 2 will be orders of magnitude greater. Ever work on Pontiacs much? Even the mildest of those engines had valve spring pressures in the OMG range. Never could understand why they felt it was necessary, and surprisingly they didn't seem to suffer much from camshaft failure. Chevy though, was another matter. Anyone telling me that the small block Chevy hasn't suffered from camshaft failure issues since 1955 just hasn't worked on too many of them. IMO, changes to the oils just exacerbated what was always a problem.

[@akallio9000]

The laxness in quality control extends to almost all automotive parts nowadays. I was watching a mechanic in a local shop working on a 10 year old car and he mentioned that the right front wheel bearing was rumbling. I asked him why didn't he put in a new one and he said that bad as it was, the old OEM bearing would likely outlast a new OEM replacement.

[@E66_h3ad]

I don’t know if you read these but you’ve helped me along so much with my 327 build. I’ve been watching so many videos trying to get the right geometry but nobody compares to the quality, length and knowledge packed into your videos. You’ve taught me so much about engines and for that I’d like to say thank you and to keep up the great quality videos. I’ll probably give an update in a month or so how my motors going. Take care

[@howitzerman]

I have had a 383 small block Chevy with a flat tappet Crane cam in my 1955 Chevy for 21 years. I begin to have issues about 7 years ago. Everything that you said in this video makes perfect sense. I just had a new 383 built by Jeff Taylor Performance and he said he will not build a engine with a flat tappet cam. He used a hydrolic roller cam and lifters from Bullet Camshafts. It was dynoed at 500 hp. Thanks for the excellent information. I am better informed.

[@christophgroat4725]

I have to say, I agree 100% with this video you've made. I've been a machinist and builder for 25yrs, and built my own stuff before that since the mid 80s. I've Rockwell tested lifters and cams also, and haven't seen much variation either.

[@briang4470]

It's so sad how you used to be able to buy a mild flat tappet cam kit for $300 or less, throw it in and pick up a decent boost in power and get some great sound out of it, but now unless you want to play camshaft roulette you now have to drop $1200+ on a roller set up all to get the same results as what a $300 flat tappet would have gave you years ago. Also not sure if it has effected you much but I know a lot of people have been having quality control issues with the aftermarket hydraulic roller lifters where the lifter bleed down as soon as you shut the engine off, resulting in a bunch of valve train noise as well as some peoplr having the riller wheels lock up and fall apart. But ALL NEW PARTS in the automotive world have been so problematic and quality control is totally non existent anymore, Soo many parts arrive dead right out of the box, parts are constantly mispackaged or damaged and parts that used to be common and readily available a few years ago are now non existent and on an indefinite backorder and what parts are available are junk and extremely overpriced due to the rising inflation, the automotive world is in a bad downward spiral right now.

[@frigglebiscuit7484]

@@J.R._ i know a guy that had a 383 stroker sbc. he had a retrofit roller setup, and one of the lifter link bars broke, and the lifter turned sideways.

[@chrishensley6745]

Seen that on comp cams Roller lifters where they bleed like that.......sad when you try a good name brand.....supposely.

[@chrisw5837]

Not if you are a cam manufacturer, just triple or quadrupled your sales….

[@larryjohnson8089]

Sir you are a wealth of knowledge, wisdom and logic. Thank you for sharing that with the internet. Great videos.

[@chuckg9805]

Thanks for the info. I think you hit the nail on the head. My next build will be a roller, I'm tired of fighting a bad cam and lifters!

[@michaelgreer8659]

Lifter crown, lobe shape, cam position and end play are everything. Another thing I think contributes to more failures is more people using higher ratio rockers and heavy springs. Keep in mind the higher the ratio the rocker is, it puts more load on your cam On a heavily loaded primary valve train, you may be better off with rollers.

[@SMOBY44]

Thank you for an in depth look at this issue. I do still believe a lot of the cam failures out in the non professional world (me included) are related to the issues you touched on, like big spring pressure, idling at initial start up, improper lubrication. The other two issue I keep seeing are guys that are impatient and just want to start it up to "hear that lope at idle". The other is the engine isn't ready to start, like ignition timing is off, carb is dry, firing order is incorrect, and they crank and crank and crank, mess with it and crank forever again and again. I was taught the 2500 rpm 30 minute break in with my first build at the age of 14 in 1982. Always used non detergent for break in, change the oil immediately after break in. I build at most 2 engines a year and have yet to deal with a cam wipe out. With that said I also hear about guys wiping a cam and just changing the cam and lifters and wiping another. Well duh, the engine is full of metal paste and will be until fully cleaned. Keep up the vids, I send folks your way every time I get the chance.

[@musashinagatsubo9574]

Excellent, taking the channel to a new level!! Qualty is not a Chinese strong point currenty, just saying.

[@craig8187]

Lobe profiles have also changed a lot. The typical old school cams had a lot of seat duration and a lazy lobe with low lift. I use a lot of flat tappet stuff still BUT i do not use some of the very agressive lobe rate cams that are very common now. This approach keeps spring pressures to a minimum which is a huge factor in flat tappet life. If you want aggressive lobe rates and big lift and want stuff to last go for roller.

[@frenchonion4595]

Yep flat tappet is just harder on components. The cam diameter in the older engine's is smaller too so the ramp to peak lift is more extreme. Later engines like the LS use a larger diameter cam to make the transition to peak lift smoother

[@flinch622]

There is something to examine regarding ramp intensity vs oil. An old muscle car cam might have as much as 30 degrees between 0.006" and 0.050". Everybody making cams reached for more area under the curve and now 16 degrees is not uncommon. Think the harshest spec I ever ran across was 14.5 degrees. Did we break something, I sometimes wonder? Bill Jenkins had an engineering degree under his belt, and did some prolific writing his later years thanks to the internet. If I read his stuff, its down the rabbit hole - an hour or more gets burned as one link leads to another. He was reasonably assured of zddp it seems to me, and that makes sense: its what he won with and found success. Yet... there is more than one way to skin a cat, but it takes a chemist these days [which I am not]. Of note, the business of "break in" procedures growing in acceptance from somewhere in the 80's also paralells the offshoring of quite a bit of American business, so there is no single convenient thing to point at and blame. But isn't it interesting that the bloom of cam failures seems to go hand in hand with the number of break in routines done? Detroit built millions of cars in the 60's and 70's with flat tappets - I doubt they had more than 5 minutes per engine to prove it operational with good oil pressure, set idle speed & mixture, and kick it out the door for the assembly line. Cam grinders are for the most part... good machinists, who just maybe got sold low grade oils where the base didn't rate good enough for use under the big labels? Hm.... Think I will give calcium sulfonate a look, and not get all ocd about zinc, and... I am going to avoid a "break in" oil my next build - just to see how it goes [but with prelubed lobes]: I have a solid/flat cam with 17 degree ramps that ought to make for a good test.

[@travissaffery]

Probably the best explanation of what's going on with these flat tapped cams nowadays

[@Clydes.Shop78]

In the past year I had two cam issues. The first was in a SBC and the lifter collapsed on the second start after break in. The second was in a Ford FE where the lobe/lifter wiped themselves. I heard all the you did or didn’t do this…the FE had already broken in a cam. Stock springs…. I used break in oil/lube etc. How many times have you bought a new aftermarket parts and it been the absolute best quality…it’s rare now days. I’ve switched to rollers for now. Might try the the “tool steel” stuff in the future.

[@2old2rodeo]

I work in a different industry but I suspect some of what I see, is going on in the cam and lifter industry. Experienced (old guys like me) retire or die and their knowledge goes with them. The new guys get very little and sometimes very poor training and are left to figure it out on their own. They have to figure it ALL out rather than getting the knowledge passed down. The fact that there is a lot of turn over in employees, and that a lot of people don't want to work, or just don't care about quality, doesn't help. I fear it a generational thing that is only going to get worse. It's why I don't eat out anymore. I don't trust those who are handling the food. Thank you for passing on your knowledge!

[@Bobthebuilder.69]

I just freshened up my 383 Chevy recently and went with a comp flat tappet cam and lifters. I used Brad Penn break in oil (30 wt) and after breaking in the cam I switched to Brad Penn 10w30. All is well, sounds great. Great oil pressure. I am gonna definitely go roller on my next build. You get alot more engine life usually with a roller.

[@howabouthetruth2157]

I would tend to agree with your last statement. I'm 61 yrs old, and if memory serves me correct, it seems like the vast majority of daily driven engines ( not even talking about high-performance racing, but maybe add in some of the "street/strip" stuff ) produced ( or rebuilt ) back in the 60's, 70's, usually averaged around 150,000 to 180,000 miles, and those motors were pretty much tired & done. But for the past 20 yrs or so, it's common to see engines living ( the better designed platforms anyway ) beyond 250,000 miles. In addition to roller cams, just overall better technology throughout every component in these engines. Although I can't say I would put much faith in these latest engines with all of their fancy variable valve timing and water thin oils. I've been a SBC man for most of my life & owned quite a few I really loved & had good service from. But back in 2000, I bought a new Tacoma 4x4 with the 2.7 liter 3RZ engine ( I still love American V8's ) and after 22 yrs & 380,000 miles, I finally blew a head gasket. The bottom end was still in great shape, but I had it completely rebuilt anyway with upgraded parts. This little 3RZ has been the most dependable & durable engine I've ever owned. I beat the living snot out of it at work, always towing work trailers & boats on the weekends, if not running the swamps & trails. I know some folks running the same engine, who were not as hard on it, and they are now beyond 500,000 miles & still going. Toyota quit making the 3RZ after 2004. I don't believe these newer engines with VVT & thin oils will live that long. I could be wrong. We'll all just have to wait & see I guess. Speaking of your Chevy 383, my buddy recently built a Chevy 383 stroker ( NA of course) to run in his airboat. That engine is a beast. Wish you all the best with yours.

[@bluegrassman3040]

@@howabouthetruth2157 have a 2013 Camry with the 2.5 engine that requires the 0w20 oil. It’s got 218,000 on it, and still purrs like a kitten. It also has the VVTi. I drive it 45 miles one way to work. They key is changing the oil every 5,000 miles and not 10,000 like most are doing.

[@howabouthetruth2157]

@@bluegrassman3040 Anyone still remaining who changes their oil every 10,000 miles are those who watch far too much TV and not paying any attention to the real information that has been circulating for quite some time now. You are very wise for changing it every 5,000 miles. While it's great that you're at 218,000 miles, any of the better engine designs have been expected to get at least 250,000 miles for the past 20 or so years now. The real test remains to be seen: getting well over 350,000 miles on it, or even more. There's a fella featured on youtube who ran his 1st gen Tacoma 2WD with 2RZ engine ( same block & head as my 3RZ, but with a shorter stroke bringing it down to 2.4 liters instead of 2.7 for my 3RZ ) to 800,000 miles before finally blowing a head gasket. He opted for swapping in an entirely new 2RZ engine. He delivers the hardcore narcotic drugs to anesthesiologists all over the eastern part of America. He drives more miles in a month than many do in a year. He now has over 1 million miles on his little 1st gen Tacoma. You can check it out for yourself, it's really amazing. Everyone was curious about what the odometer does when it hits 1 million, and the answer is: it just sticks @ 999,999. It doesn't roll over to "0". So now he has to keep his mileage logged by hand, in a paper tablet. Best of luck, and hopefully you prove me wrong ( and many engine builders I know who don't hold much faith in these newer engines either. ) And believe me, I'm the type of guy who will admit if or when my hunches & assumptions are proven wrong. I hear crow doesn't taste half bad with plenty of salt, lol. Stay safe out there.

[@carlstephens1532]

@Howabouthetruth I put a 350 in a S10 for service work , it carried 1700 lbs of tools And towed a trailer every day. I had put the forth engine in and started changing the oil after the first quart disappeared usually around 20,ooo miles , that engine had 537,000 on it and I took it out , torn it down ,took everything to a racing machine shop , no work was needed ,all parts were good , nobody in the shop could believe it , I reassembled the engine and after another year of working, making money. It ended up on the local drag strip and , I won king of the track ,and king of the hill titles, at the Gainesville raceway , I was offered a very large amount of money for it and sold it,, that person raced that truck for several years before he. Sold it to another racer, so it lasted, I used mobile one with prolong added , and still use both , my suburban has 250,000 and my 1500 Chevy has 390,000 on it and gets 28mpg , and l've have it 18 yrs now as a service truck. Luck maybe but I think after working on street and racing vehicles my whole life I believe it's the oil and proper care.

[@RichMander1]

Going with nothing but roller cams is easy to say if you’re cranking out Chevy engines all day. Two problems with this. The first is that there aren’t any roller conversions for things like slant sixes, and AMC 195.6s. My customers don’t want an LS crammed into everything, they want their car the way it was. The second problem is that people I build engines for don’t want .600 lift in their street car. Most retrofit roller setups have a ridiculous cam profile, and most of the cars I work on are old bread and butter sedans, and daily drivers. They want a nice smooth, torquey, no hassle car. I realize my customers are the absolute minority, but that’s what these cars used to be.. Cars. Is a ‘72 Tbird with a 460 fast? No. It wasn’t meant to be. It was meant to cruise the highway at 80 all day in total comfort. A rambler wagon wasn’t meant meant to run 12s. I’d love to see more realistic cam profiles in roller setups.

[@gurneyforpresident2836]

Thanks for this. Well said and very true. Plus I am Ford man and they can put the LS where the sun don't shine.

[@msgofast]

Is there a reason you can't run a roller lifter on a flat tappet cam?

[@barrycuda3769]

@@gurneyforpresident2836 Just about every Chevy in the Autotopia la videos is fitted with an LS ' no regard for tradition 'is that possibly because carburetor's are seen as naughty now?

[@barrycuda3769]

Thanks for being real on this subject ' a lot of us are just enthusiast restorers of classic cars .Could you advise me on the following' I live in New Zealand and I'm going to be rebuilding the 225 slant six for my 66 Valiant .A supplier in Australia has rebuild parts for slants ' the cam and lifters they have are "Melling " I've always perceived that to be a quality brand. I've become aware of problems with cams and lifters 'and the last thing I want is a failure in this area .I threw out my original cam 'so I'll have to go brand new for that 'but should I just get my original solid lifters resurfaced? Should I get a high zinc oil for break in (and thereafter) Do you know of suppliers in America of quality slant parts? Any advice would be much appreciated .

[@RichMander1]

@@msgofast I’m by no means an expert on the subject, but I assume most of the reason has to do with cam profile. If you look at a flat tappet cam, the lobes come to a more extreme point, and are much more egg shaped, whereas the roller cam has a broader ramp, or shoulder leading to the top. A roller lifter might chatter at the top, or be forced into the sides of the lifter bore with the bottom of it trying to climb and fall off of the sharper ramp? Dunno. Just guessing.

[@robertnelson3734]

Very, very good video. I had a flat tappet cam failure in the early 80s due to improper break in amongst other things. On my new FE stroker build, doing roller cam/lifters. Worth it. Thanks for your good advice to novices.

[@Myvintageiron7512]

Glad it helped

[@GregHuston]

There’s 1 flat tappet lifter producer in the USA: Topline Hylift in Muskegon MI. There’s only 2 Cam core Forgeries in the USA Textron also in Muskegon and they supply 80% of the cores (CWC is stamped on these). The other is in Ohio and the name escapes me at the moment. The Federal Mogul lifters and other name brands are made in Mexico. You’d also be surprised to know Jeep was running flat tappet cams until 2006!

[@frigglebiscuit7484]

stay away from mexican lifters.

[@thisisyourcaptainspeaking2259]

Thanks, I'm still running flat tappet without issues in older engines built to factory spec.

[@TatersUnited]

The good ol 4.0!

[@Schlipperschlopper]

@@thisisyourcaptainspeaking2259 I only use Elgin cams- never any problems yet!

[@cmartin6189]

Great video! Just wanted to say I now use a dial indicator check on my lifters, along with holding two of them together face to face up to a strong light to physically see the gap and measure it with a feeler gauge, for all 16 lifters. Then measure cam taper with a vernier caliper on every lobe to check that it has 2 to 3 thousanths of taper. Unfortunately this is time consuming for most people but with todays flat tappet cams you have to do it. Its added peace of mind. Before putting the cam in the engine.

[@MrXerxes415]

Thank you for this insanely helpful information with a very understandable culprit many people are extremely whiny and feel like they can’t justify a roller cam but it is the way to go and I think you’re always gonna be better off if you do

[@howardgaither8759]

Believe m we, it's lubrication, I found out over 30 years ago, oils offer very little protection in high pressure loads. I have been selling a product that increases the load bearing property's of oil over that of oil. Don't believe it, I have had customers that ran old trucks way past their normal life with oil. How about loss of oil pressure or water, I have had a number of those things happen, they just added oil or water, or repaired failed oil pump, that engine is still running today after running 30 to 45 minutes with out oil pressure. Do some research there are things out there that work beyond your wildest dreams.

[@davidpurifoy7985]

Thanks for sharing your knowledge. This video and information has been needed for years. I, like you, quit using flat tappet cams years ago, unless we are forced because of rules. (i.e. dirt track engines) Before I offer my experience let me say, it only cost around 6-800 bucks to add a hydraulic roller set up. As you mentioned it cost much more than that to repair an engine that has a 1/4 cup of powdered cast iron running around its inner parts. I have an engine dyno service. Last year we broke in and tuned 105 small Chevies that had flat tappet cams, Some hydraulic, some solid, because of rules. Only one or 2 had any issues.These engines had 140-150 lbs spring pressure on the seat and around 340lbs open. They all had a good break-in oil. (Maxima/Gibbs/Comp cams) With that said, most of the cams only last til the first rebuild/freshen of the engine. So at best a flat tappet MIGHT make it past break-in on a race engine but not past a season or so of only running on the weekends. Not a gamble I would take on a street engine. I believe you to be correct about the manufacturing tolerances/procedures to be a big part of the problem. As far as oils. There is a great website (540Ratblog) where an engineer tests wear protection of oils. It is really interesting but not the final word in my opinion. Just one more piece of info... I built a reverse rotation 351W for a boat application. I wanted to put a roller in it but No none makes cores for a hydraulic roller reverse rotation cam. I bought springs, cam and lifters from Comp just in case. I bought the oil that the 540 rat blog guy had listed at the top of his list as the best wear protection! Stuck it on the dyno and ran it 7 minutes. 15 bad lobes. Not only were the bearings trashed but the cylinder walls and piston skirts were so scratched up I bored it again and replaced the pistons. Comp warranted the cam and lifters. Sent me another one and some of their break in oil. Stuck it back on the dyno and as far as I know its still running up and down the lake. That was 3 years ago. Thanks again for sharing

[@Myvintageiron7512]

Thank You It's interesting how shops that are actually performing this work are coming to the same conclusions, Thanks for the tip on 540ratblog I saved it to my favorites and will be reading the info

[@misters2837]

That 540 Rat Blog is some of the biggest line of BULLSHIT I have ever read.... His idea of when oil is breaking down is when he sees "smoke" coming off the oil...its not very scientific, and he does not reveal where he comes up with his pressure number either... PURE SCAM IMO.

[@dennissherman8776]

Completely agree, been building engines for almost 5 decades, Truth in everything you said. In my opinion pay attention people this man knows of what he speaks. Again well said sir. Thank you for sharing your knowledge. Gotta love old iron. Keep em on the road

[@tomnekuda3818]

You've given a veritable encyclopedia of good knowledge in this upload! Thanks.

[@earlwhite2620]

I owned a Cessna Aircraft Dealership in 1977 and The Lycoming Air Craft Engine on the c152 and other single eng Cessnas from 1975 and up were wiping out camshafts fast. The Lycoming answer was the oil needed an additive every 100 hrs of run time. The problem was two fold according to therou. Unsold Aircraft sat without renning at the factory and there was a new camshaft and lifter combination. The lifter was like a car engine in that it was removable with out dissemebly of the engine. The "snake oil" fixed the problem. A great engine after that. Earl White

[@Schlipperschlopper]

In Germany we always add 2% Mos2 additive (Molykote or Liqui Moly made) to the engine oil

[@BobVan]

I’m in middle of putting my old 74 sbc back together after a full rebuild and opted to switch over to a Howard cam roller lifter combo retrofit kit. My engine had originally wiped out the original cam probably from years of running inferior oils in it. I figured out about the need for the additive upon doing research and just decided roller lifters are more superior anyways (if it’s a good brand). I’ll still use the break in oil and the extra zdpt stuff because it’s an old engine and I don’t have a catalytic converter. It’s just not enough to fix something. Sometimes you gotta figure out why it failed to begin with. Thanks for the vid. It helped reinforce what I figured out in my situation.

[@tylerpangerl]

Great video. I absolutely love listening to wise builders like yourself and others that have lots of experience and information to help further my own.

[@Myvintageiron7512]

cool Thanks!

[@geraldscott4302]

You hit the nail on the head at 13:40. The problem is POOR MANUFACTURING STANDARDS. There is no reason why a flat tappet cam and lifters can't last just as long as they ever did, IF the manufacturers made them right. That is what needs to be fixed. In fact it can actually be improved. There have been significant advancements in metallurgy since the old days, and there is no reason we can't build engine parts that can survive with the garbage we have for oil these days. Roller cams are fine, but they are not available for all engines, and that especially includes the engines that hot rodders and amateur drag racers use. I rebuilt my first complete engine back in 1973, at the age of 14. It was a 1964 Chevy 283. I used STP oil treatment for assembly lube. It went into a 1963 Chevy Nova SS. It was not my car. I know for a fact that that engine lasted at least 5 years with no problems, because the owner kept the car for that long before selling it, and it was running fine when they sold it. As for EFI and any kind of emissions crap like cat cons, I don't mess with any of that trash. I build and rebuild ONLY vintage American engines, though I have done a few air cooled VW engines. I have built engines from near stock daily drivers to full blown drag race engines that ran in the mid tens. I have used roller cams and lifters, but far more flat tappet cams and lifters. I have also found brand new cams and lifters with no taper and no crown. I have no way to check the hardness, but I'll take your word for it. But the question is, WHY are cams and lifters being made this way? And whether anyone likes it or not, in my opinion it is because what were once American companies are having their parts made in CHINA. I could write a book on how many JUNK parts I have found from China. Pretty much everything from China is JUNK. And that includes parts for brand new cars and motorcycles as well as vintage parts. A friend of mine who is a service manager for a new car dealership told me that a lot of failed parts removed from new cars were JUNK, and the new replacement parts were also failing. The one thing those parts had in common was they were made in China, Thailand, Korea, Mexico, etc. I totally agree that putting a ZDDP additive in HD oil is not a good idea for break in. But most oils sold today do still have some ZDDP in them. Just not nearly as much as they used to have. It's actually the phosphorus in ZDDP that caused a problem with catalytic converters. But since I don't deal with cars that have catalytic converters, that is of no concern to me. Lucas makes a great break in oil, part number 10631. As far as spring pressures and aggressive cam profiles, yes you have to take that into consideration. If you are building a drag racing engine, or a hot rod street engine, use a roller cam if one is available for the engine you are using. Fortunately the engine I deal with the most, the pre LS small block Chevy (carbureted) can use roller cams and lifters. But this problem with poor quality flat tappet cams needs to be solved. The survival of a whole lot of vintage cars out there depends on it. Remember, REAL cars DO NOT have computers.

[@jeffjankiewicz5100]

Thanks for taking the time and effort to clear this mystery up. You presented your facts clearly. Always a learning experience in your videos. Thanks.

[@Myvintageiron7512]

thx

[@macfranks2456]

I agree with most all of what you have said on this with perhaps one aspect I don't completely agree with. It isn't just flat tappet cams and lifters that have been failing. The roller lifters and cams are failing too and that includes the $1000+ Iskys and Crowers. The frequency of failure may be less but the reports are still coming up online all the time. When a roller fails it doesn't just throw some powdered metal either. It can and often will destroy the lifter bore and potentially wipe out the block. I am at a cam decision right now on my Cleveland build and frankly, I don't know what to do. Its been a while since I have put an engine together and my last one was a hydraulic flat tappet 302 for my truck. Runs perfect. I have a couple of hydraulic flat tappet cams and 4 solid flat tappet cams in 2 different species of engines, all of them perfect but all of them older than the past few years.

[@sunnyray7819]

Uncle Tony recommend this video and channel. This is a topic he was trying to get to the bottom of and your video is a help to all .. Thanks!

[@Myvintageiron7512]

Thanks for that

[@rodallen1357]

I agree with your findings, I suspect that some cam companies don't change the cam grinder machine angle for flat tappet taper from roller lobe straight across. I also agree that the crown is not being ground correctly. With regard to hydraulic roller lifters, I have had trouble from one major cam company (CC) internal tolerances, it was so bad the leak down prevented the engine from firing evenly. As an engine builder with 50yrs experience, I too will not build another flat tappet engine.

[@rickss69]

That doesn't address the hydraulic roller failure you referenced...

[@isaachousley325]

Nah, its definitely out sourcing. Completely different set to grind the face on a flat tappet lifter than whats required to simply machine the straight cylinder and pin holes for a roller lifter.

[@WallaceCustomMotors]

Thank you for you always amazing and ever so helpful videos. I’ve learned SO much from your videos. Since finding your channel I’ve built almost 2 dozen engines over 2 years for a hobby and side job. Have yet to build one for myself lol. Keep the great videos coming!

[@Myvintageiron7512]

cool Thanks!

[@silicon212]

The last flat tappet engine I built was in 1993. The next engine I built for myself was in 2012 and it was an SBC 350 with a roller cam, for the very issues you laid out. I inherited a car from my dad when he passed in 2015, was a 1967 El Camino undergoing a restoration. The engine in it was a 350 as well, with a flat tappet cam. I am the one who fired it up for the first time, and I followed the break in procedure that I had used since the late 1980s, 20 minutes at 2k-2500 RPM, shut down, change oil and go. It wiped a lobe around 10 minutes in. I obtained an L79 cam NOS with NOS AC lifters and installed that after thoroughly cleaning out the engine of metal from the previous failure (which was shut down almost immediately upon beginning to misfire). This time it lived, and continued to live when I sold the car in 2022. The oil I ran in the engine was Rotella 15w40 for the ZDDP content. As of the mid aughts, only lifters from GM or from COMP were not experiencing these failures. I don't know if that has changed since, I don't expect that GM continues to make them today considering the last SBC with a flat tappet cam was installed in a 1995 Chevy truck (which I always found odd considering that 305s and 350s installed into passenger cars got hydraulic roller cams in 1987).

[@stevestock2439]

Thanks for taking your time explaining this. What do people do that are rebuilding non performance vintage engines like your 305 GMC V6 build you did a few years ago? Break in oil with zinc additive and 2000rpm breakins? The spring pressures are so low, maybe there is forgiveness there. I have assembled three stove bolt inline 6s in the last four years, all flat tappets low perf engines and used Rotella T4 to break them in without issue. Believe the T4 has 1200ppm zinc

[@andyay1306]

@stevestock2439, hi steve I've been using Rotella with 1200ppm Zinc to break in my freshly rebuilt flat tappet OHV motorcycle engine but saw large amount of particle like metal shaving, I suspect it could only come from the tappet. In theory T4 has high zinc but also high detergent, so it should work as wel as the video suggest detergent and Zinc isnt compatible. Whats your thought in this?

[@darrellbriggs6674]

Well explained mate,hit that ongoing subject on the head. Love your work mate. From Australia 👍

[@25bikertrash]

Excellent breakdown. If the extra cost of a roller setup is a deal breaker, you shouldn't be building it, or be into this hobby altogether.

[@davidkeeton6716]

F U

[@borismcfinnigan3430]

Wankjob. Some of us like our flat tappet setups and have grinds that work perfectly. You cant just copy a grind either as the ramp rates are different from flat to solid, so there goes all the years of developmemt because people cant make parts properly.

[@ws2664]

Now that has to be the best explanations i have ever herd!

[@scottgulkin]

I definitely agree. At the cost of engine parts and machine costs now all my future builds will be roller cams. It's just not worth the risk and 20min of stress to break in a flat tappet when a roller cam adds about another 800 on the build to stand to lose over 3 to 5k in a single engine build. Also, I would agree that lifter spin would be linked to failures and that lifter geometry has alot to do with it. In the Crane break-in procedure before they went under, they had a step to right away check for rod spin on startup to verify lifter spin during the break in to prevent a wiped lobe, so I'm sure they were aware of the main causes of failure.

[@kevinlowe4845]

Hey pal, in 1991 I bought a 1956 Chevy 1/2 ton pickup,I had a 1964 283 cu in motor, I used all stock components (jegs summit and local parts stores) I have not had the intake or heads off since I rebuilt that 283,new air filter and oil change every 2000 miles,I have used this truck for my daily driver taking short trips,no problem, I watched your cam break-in video,just what needed,take care my friend

[@Myvintageiron7512]

cool

[@cammer68oliver2]

True… roller is better. But yeah, more expensive. That’s why I went flat tappet in 2012 when I built my 347 stroker SBF. I’ve had ZERO problems with that Comp Cams cam that I put in there. Once I had a polylock back off a rocker and the clip and pushrod seat on the lifter popped out of the inside of the lifter. I got lucky, no major damage done. But! I had to pull the intake to fix it, obviously. When I pulled the lifter out of the bore IT WAS LIKE BRAND NEW! 6+ years of hard street running! Fast forward to now, post-covid and here I am rebuilding my dads 350 out of his ‘78 K20 pickup and I’m looking at 16 munched up lifters after only 16 minutes of runtime not even finished breaking in the cam. I did the same install and break-in procedure as I did for my stroker. So in my eyes SOMETHING CHANGED. To me I still believe we’re getting inferior lifters from China. As you say (partially) the cam manufacturers aren’t to blame. They didn’t make the lifters. I believe covid caused a shortage in lifters made in the US and what we got now is junk from China. So now I gotta clean that entire engine stem to stern and reinstall a new cam/lifters (thankfully warrantied by summit) and pray to God it takes this time. SOMETHINGS AH MUCK HERE! Can’t convince me otherwise

[@richardsmith-qy6vl]

I agree with you 100% I tell people all the time don't waste your money on flat tappet cams it's so many problems if a lifter hangs up in the bore and don't spin to much spring pressure not adjusting the valves right ang having them to tight with to much preload and the wrong break inn rpm and letting them idle and the wrong oil like you said people say they can't afford a roller ok then buy a few flat tappets until you get lucky or realize you need to go with a roller nick at nicks garage has had the best luck I've seen in the last few years. I bet if you told the cam company's they had to pay for a rental car if a person buys a cam and it goes flat and pay for it until the motor was right they would either step up there game or stop selling them my engine builder built a DZ 302 with a flat tappet cam that just set a NHRA record the cam only had 480 lift the motor made 575 hp and ran 10 seconds in a 3100 lb car he's been building race engines for 56 years. Anyway great video your friend from Louisiana Rick 427

[@LuvTruckGarage]

Great video, lots of good information. I think you nailed it with the manufacturing issues. Quality control is not what it once was in a lot of products these days.

[@donstieben3939]

Another thing that is missed is the position of cam in the block. The lobe must have offset when looking down through the lifter bore. Lifter crown ,cam taper and cam offset create lifter spin. The cams offset is controlled by the timming gear and the oil pumps drag pulling the cam rearward so a cheep gear can give incorrect offset. The more offset without causing the edge of lifter scraping the lobe the better also the rpm at break in needs to keep changing and not just set at 2000 and parked there the whole time and never idle. This is a great video and so much correct info to all new builders pay attention to this one.

[@mk-xg2kt]

"Another thing that is missed is the position of cam in the block." have thought about that a lot. you can move camshaft back and forth in the block. I have tried it in a slightly different position. but never started the engine "didn't dare". just looked at how it looks. I have seen that it looks a little different with different camshafts and blocks when you assemble them together, without moving them. if I Know what the correct position is in the block. then I would make sure it ends up there. but I don't know what dimensions it should have?

[@borismcfinnigan3430]

horseshit. The whole idea of the rpm is to sling oil up to the lobes. Varying rpm is not required at all.

[@donstieben3939]

@@borismcfinnigan3430 the varying rpm helps to change the load and will help get a lifter spinning that has started to stall at spinning ,if you mark the pushrods the lifter spin is easy to watch with clear valve covers or no valve covers and engine running and yes the rpm does help sling oil but the change in rpm also helps change the oil delivery

[@donstieben3939]

@@mk-xg2kt the position of the cam doesn’t have an exact measurement because manufacturers don’t make cams to a consistent dimension it’s just one of those things you take notice of and make a mental note so when looking at a setup you can spot if the lobe is offset in the lifter bore hole. After building motors for years it’s an easy thing to see but hard to explain or help others with but just start paying attention to motors and cams that fail and others that worked and you will get a feel for it

[@StephenGiovi]

Thanks for the info. It was informative, and I will surely take your advise very soon - I have three or four flat tappet cams from Summit Racing, Isky, and Crane that I still have not used for different reasons. See ya!

[@barrychandler5250]

I will take your advice and swap to roller cam/lifter setup in my old school build.

[@johndouglas3724]

Thank You sir....about to build up my old 73 camaro as a newby...i will budget for Roller....thx for your honest advice!!!

[@terrydolbow4299]

Good info about this subject! But what I want to know is what is going on with timing chain's that have a lot of play in them! Thanks for the video

[@maxs.5905]

I was still kinda on the fence about spending the $1200 for a Howards #240705-10 cam and roller lifters. After watching your video I have to agree with you. I built a 460 and had it on my engine run stand. I had 3.5 hours run time on it from starting it every week. I installed an hours meter to keep track of the run time. I had a persistent oil fouled plug on the #8 cylinder. I was sure it must be something with the oil control ring so I tore it all apart. I was very surprised to find four lifters with a strange uneven circular pattern. All the other lifters looked brand new like they were never run. The cam was a Summit #3500 very mild cam. I had no valve train noise but apparently was about to. I used Lucas 30wt break in oil for 25 minutes and a Mobil one filter. I drained the oil then refilled with Lucas 30wt and a new Mobil 1 filter. I started the engine every week and ran it up to 180 degrees always keeping it at 1200-2000 rpm. I only let it idle about a minute prior to shut down each time cuz my headers would glow red. I never had cam problems before this

[@richardrichard4394]

Use a good break in oil with no added detergents or zddp additives proper chemistry and assembly lube, rpm, spring, rocker pressure all good works for me Great video

[@barnhousegarage]

I've been a mechanic for 30 plus years and have installed many flat tappet cams with zero issues. I just installed a comp cam and lifters, valve springs, and retainers in a big block chevy and with 20 minutes of 2k rpm break in the cam and lifters are coming back out it's acting like the cam is flat already,I've never had any issues with flat tappet cams I'm guessing the cam and lifters are of poor quality as is the issue with many aftermarket parts these days

[@nitromyke]

Thanks for the info!! Other youtubers brought this issue, but your tech insight is above all the rest!! Keep the good work coming Sir!!

[@tonyc223]

If your lifter does not start and continue to spin at star-up or if fails to pump up in a reasonable short time your on your way to a failure. Yes check your lifter bases,proper spring pressure, proper oil ,rpm you know the rest. And high rpm is good break in for the rest of your new engine parts.

[@MikeJones-zj5lj]

Strange thing is, we(Jones Cam Designs) manufacture about 300 flat tappet cams a year, mostly for circle track racing, and we don't have cam failures. So far, in 2022, we have lost one cam. It's all about the machining quality. If you're having failures, you're buying mass-produced junk.

[@isaachousley325]

Yep. Everyone is quick to blame failures on "Chinese garbage" while ignoring the facts. Ive watches several videos from knowledgable sources now and heres a few take aways: 1. Alot, if not the majority of your aftermarket cams, no matter the company that grinds them, start their lives as cam blanks forged by 2 companies in Michigan. Yep, they are USA steel, not Chinesium. 2. The cam hardness isn't the issue. Once again, the cams are coming from 2 US companies as blanks and then ground to whatever profile the the name on the box wants. Its also been noted that the harder cams actually wipe out more often, as the harder material wears away the softer lifter faster. 3. Zinc. No, you off the shelf pour in zinc additive wont protect your cam any better that off the shelf oil, nor will the diesel oils. Check out lake speed JR for a better explanation, but basically the type of zinc differs and and theres a process during the oil blending that actually causes the zinc to be properly suspended in the oil (which your off the shelf snake oil zinc additive doesn't do) for it to actually work. 4. This is the coup de grace of the issue as confirmed by several sources: lifter machining. A flat tappet cam and lifter is a metal of metal interface; if the machining angles dont match close enough, all the resistance of the valve spring is going to focus on one small point instead of the entire surface that is supposed to interface. The result its that the lifters dont spin, and one side of that focused point is going to eat into the other as the cam spins. Unfortunately, it seems alot of the cam brands are simply reboxing cheaply ground lifters or aren't employing adequate quality control on their in house lifter grinding. My assumption is that most have out sourced their flat tappet lifter grinding to 1-3 companies as there just isnt the volume of flat tappet setups being sold to justify it being done in house.

[@chrischeney4384]

So good to know, my mild build 350 made it 7000 miles and ate the cam and lifters. Now I'm hoping the comp cam retrofit lifers and roller cam last a little longer! Hurts to spend another 1200 on better cam and lifters in addition to another rebuild kit but oh well!

[@stevenhobbs709]

Thank you for some very good information, I’m glad we can still buy oils with zddp & zdtp here in OZ, still makes roller cams even more attractive.

[@MisterTwister222]

I love your hate for flat tappet, its one of your most endearing qualities.

[@overbuiltautomotive1299]

so basicly i need to send my new cam and new lifters to Delta cams for checking and regrinding or just do a regrind on old cam and lifters .or just get a roller set up and avoid all that doing crap twice and and metal in oil sounds like a winner Thanks for videos

[@Squares.SSs.and.Bowties]

1st off hats off to vintage iron. Your videos are interesting and seem to be on point. Im a 55-60 yr old guy thats been playing w Chevys since the age of 15. In my experience I've had a dozen or so new engines. I started buying Target Master engines from Chevy then Goodwrench etc. At some point a top shelf engine builder (Long Island NY community) got my ear and convinced me to buy custom as opposed to of the shelf GMPP. So I did. His engine failed. Not immediately but cam lobe dimensions were all over the map! No lobes were round but they werent what they started out at either. I went to a 2nd and a 3rd builder. Still real strong reputations. They're engines failed as well. All the Target Motors or Goodwrench engines lived! They lived heartily I'd add. My needs are for towing vehicles. I run a residential excavation business and move my equipment around with 1 ton squarebodies- all of my trucks get the same treatment- rebuilt 350 or 454, rebuilt sm465 trans and 14 bolt corporates. Period. They see lots of rpm's and lots of oil changes. Everything was broken in the same way- 2000 rpm for 20 minutes, proper breakin oil changed out at 500 miles of no load driving then switched to rotella 15-40. As far as I know Rotella still has 1100 - 1200 count of additives making up zddp. The GMPP engines may have come out for burned valves or every gasket is leaking. I give it a thorough refreshen and repurpose it... reliably! The custom engines- ugh reused for parts- scrapped etc. So the big question is... which cams and lifters are the GMPP engines being outfitted with?? No disrespect to custom engine builders at all! Super knowledgable, passionate, high quality guys & staffs. But!... the problem has to be found in cam & lifter manufacturing. If you're going to respond in a non productive way, at least include real life experiences with which cam &/or lifter manufacturers have proven reputable.

[@Myvintageiron7512]

GM has very high-quality control standards I have also used many of the Mexican made GM crate engines with OEM cam and lifters I have put at least 75 of them into service and not one cam failure, also it's important to note the cams have very small lobe profile around .400 lift and a duration @ .050 of 197 to 202 the valves springs have 70 Lbs of seat pressure and 260 Lbs of open pressure (very light spring pressures) in other words not a performance cam at all bone stock so low rpm's and light springs this all helps cam life but I also think gm is very picky about lifter and cam grinding when you start getting into performance cam grinds and heavy spring pressures the grind of the cam and lifters is much more critical

[@aaronbarnes8938]

Back around 2010 I lost my first and only flat tap camshaft and if I remember correctly that is around the time you really heard about flat taps going flat a lot. Have not done anything but a roller in my Mopars ever since. Yes, it costs more up front but it's cheaper than having to go back through an engine when those junk flat tappet fail.

[@Oscarphone]

No kidding. Cam going flat is, at least, is a complete teardown, inspection and reassemble. The extra cost of rollers is well worth it.

[@gregorymalchuk272]

The oil in 2010 was API SM which was a low water mark in wear protection due to errors in formulation. Modern API SP oil supposedly has the best anti-wear properties of any API approved oil, ever.

[@joeshumo9457]

I didn’t hear you mention ramp profiles. A cam with too extreme of a ramp angle yet has the lift, duration and LSA desired, will wipe a cam out due to the lifter edge essentially digging into the cam. This is worsened by solid lifters and high spring pressures with high lift profiles. With a low enough spring pressure and fast rate of lift , high rpm valve train instability leads to destructive harmonics as well. Aggressive ramp profiles need to be considered as that is the primary reason for roller cams to begin with along with higher spring rates in order to control instability. I use an externally pressurized oil fill system with a calibrated oil plug leak when firing up a new flat tappet cam with verified hardnesses, flat tappet spring pressures and profiles. I was born and raised in a high performance automotive machine shop 54 years ago.

[@unclejessiesrodshop8432]

I have been saying the same thing, those "new" lobe profiles work well, until they don't.

[@daveski4496]

Great info , much needed education for us users. Thank you.

[@mylanmiller9656]

i agree with everything you say, you don't need to lose to many cams before you see that the cost of a Roller is cheap compared to redoing a new engine.

[@Myvintageiron7512]

Yep the only people who still defend flat tappets are people who have not watched weeks or months of their work and a ton of money be destroyed in a matter of minutes during break in one thing I know for sure for most people it will only take one destroyed engine to make them convert to roller there are probably a few who won't but you know what the definition of insanity is keep doing the same thing expecting a different result

[@mylanmiller9656]

@@Myvintageiron7512 i have a Friend that own's a Speed shop, he almost went broke because of cam fails. It isn't the cost of the cam like you say, it is the cost of redoing the whole engine. If you are building 3 or 4 engines a week you can get into big trouble on a hurry if they start flattening Cams.

[@jimbonettles]

I went roller cam for my first engine build after hearing the horror stories with flat tappets since I was inexperienced. Another thing to keep in mind for people dipping their toes into this hobby is the engine needs to be ready to fire and go right away before breaking in the cam, wouldn't you agree? This makes considering a flat tappet cam an even more unattractive option for the novice in my opinion. So many things to keep in mind/ward off like timing, fuel delivery, vacuum leaks, wiring etc.

[@catbird1759]

Exactly. Example. I replaced 2 camshafts in a POS 1.6 VW diesel Jetta. The 3 camshaft was an aftermarket billet one. I changed oil earlier, put additive, and used synthetic oil. Pure junk. As the years went by ZDDP was being taken out of the oil. Killing this engines life expectancy. Recently in the past 3 years, had 2 camshaft failures in rebuilt stock engines. Yes, I've been going through the same thing as you for over 45 years.

[@busdriver1209]

As i write this comment I'm looking at a lifter with a hole in the bottom face of it where it failed. It came out of my Ford FE 431 Stroker motor that had a whopping 500 miles on it when it started rattling like crazy. No other symptoms up to that moment. It was running great! Not my first FE rebuild, and all cam break-in procedures were followed to a T including no detergent break-in oil with ZDDP. High pressure break-in lube on the cam. Pre-start oil priming, immediate RPM to 2000 for 20 minutes. This was a mild cam with stock heads fully compatible with the stock springs. Now I have to spend another $3500 to rebuild my newly rebuilt engine. A roller cam may be expensive but it would have saved me a lot of money! Never another flat tappet cam for me!!!

[@Myvintageiron7512]

Yep I hear this same story over and over just about 1 a week, sorry about your troubles brother I know exactly how you feel, I've been there more than ounce, you just got to suck it up and start again Going roller is a very wise decision

[@marvmiller1708]

Flat taps have worked for longer than rollers just like stamped rockers. Proper break in on the cam, proper spring tension and high zinc oil (no emission control devices) will be the three most critical things to address. Shit just build the damn engine to spec and tollerence, do the cam break in and then go drive it like it was stollen the first 500 miles in town through all the rpm ranges. This is how it was done many times with guys back in the day and things broke in properly and lasted. Thank you for your video's. But the cost for most guys with roller assemblies is just too high, especially today. It's more important to get a solid rotating assembly and heads with flow than to fret over less drag in the cam shaft assembly.

[@Myvintageiron7512]

This is exactly the problem everything you have listed here is being done religiously by engine builders and the cams are going flat, what we did in the past is irrelevant If you actually watch the video and listen to what is being said you would realize that the advice you are giving simply will not work on every flat tappet, my response to your claim that the cost for most guys to go roller is just too high, is how are they going to come up with the money to rebuild the engine over again when the cam shreds if they can't afford a few hundred more for a roller if you are not building engines with the parts that are being sold in the last 3 to 5 years please don't give advice on this subject because comparing what used to work to what is happening now is Appels and oranges also rollers have been around since 1893 in Diesel engines so I would say they have been proven pretty well.

[@TagsGarageAZ]

Hey Mr.T!!! Fellow student if yours here! Recently I’ve been experiencing 3 issues with cam and lifter manufacturing defects that you CAN NOT see with the naked eye, first problem is grind chatter on the lobes due to grinding stone loading up (the parkerizing hides it all too well until the wear pattern reveals it), second is no taper on lobes AT ALL!, also I’m seeing little to no crown ground on lifters, usually been rejecting at least 3 lifters per box due to insufficient crown. It’s getting ridiculous!

[@Just1Spark]

Engine builders: "We are going to roller cams, because too many flattys are wiping out." 5.7 Hemi cams: "Hold my beer"

[@Myvintageiron7512]

The late Model Hemi cam sets are a completely different issue, they are having problems because of a design flaw in the Hemi block itself it is most problematic with late model hemi engines that spend allot of time at very low RPM or idle IE police cars. the cam and lifters do not get enough oil. Uncle Tony has an excellent video on the subject he explains it well you can watch it here kzbin.info/www/bejne/mnqcZGCQmd2SpLs

[@Just1Spark]

@@Myvintageiron7512 Thanks. im aware. I lost 2 hemis back in 2015. I hardness tested all parts. They checked out. I just thought it was funny. A few years ago i built a 305sbc to put in my 8n ford, and i was hesitant to put a new cam in it because of all the issues everyone was having. I used amsoil break in oil, and ZRod there after. No issues what so ever.

[@steveblottenberger1097]

Keep up the good work Steve from Annapolis Maryland I believe every word you say and I love your show keep up the good work

[@Myvintageiron7512]

Thanks

[@michaeledge8905]

Just built a 350 chevy and used a Melling cam and lifters. Did everything right with break in and extra lube and it failed after 30 minutes of use. Never used to be that way. Been a mechanic for over 40 years and never used to break in cams. Now this.

[@Haffschlappe]

Melling seems to use Chinese crap Cores and lifters

[@monkeluv707]

Great information. I have a jet boat with A 460 that has a flat tappet and a Nova that also has a flat tappet and they are doing fine for now but next rebuild I am definitely going roller.

[@Only1nexus]

Thank you. You just taught me something. I will be going with the roller cams.

[@cartracer64]

good points, i have also heard of failures of hydraulic roller lifters and bleeding down.

[@bassettraceengines]

Great information! I use break in oil on all my engines including roller cam engines. Thanks for sharing.

[@Myvintageiron7512]

Thank you!

[@jefferykaighin7039]

I work for the Brown Delivery Company In the Automotive Department and was a mechanic for 2 years and now have been in Management for 32 years and all my Technicians watch and subscribe to Myvintageiron and trust what they learn and practice these instructions 1000% we are very grateful and trust everything you teach! Thank you. I going to donate monthly!

[@Myvintageiron7512]

Wow Thanks

[@ken0x34]

I just got done replacing a COMP cam in my custom 454 motor after #6 exhaust lobe went flat. I had about 5000 miles on it. I did everything wrong... used additives with detergent oil, ect... Oh well. I am enjoying the replacement roller cam, however it doesn't rough idle rumble like it did before.

[@crash1769]

Thanks Myvintageiron7512 for a great informative video. I had this discussion with a guy at the Turkey rod run show in Daytona about this same issue with detergent oil vs break in oil and ZDDP additive and adding this to over-the-counter oil. A roller cam cost 400 to 500 more but the cost of a new motor rebuild Twice was a phenomenal point. Because why it happened to me.

[@Myvintageiron7512]

Thanks for sharing!

[@skylinefever1658]

I saw some interesting results in the Powell Machine channel. What they saw was that lobe taper is wrong on some of these cams, and lifter crown is often wrong. They measured some new Isky cams as an example, but have seen it almost everywhere. I am now sure that the major cam companies no longer have passion for building cars. They no longer care about building a good part. I would buy a cam from some custom cam grinder to avoid this. I like the Jeep 4.0L, and they were all built with flat lifter cams. Roller cam conversions are super expensive for regular street drivers and offroaders. It's not that current oils have no ZDDP. They have lower ZDDP. Also, there were still flat lifter cams in the 1990s. The Jeep 4.0L was common until 2006. 10:58 ZDDP was not eliminated from heavy DPF diesel engine oils. It was reduced. That was in 2007. It was reduced more, later on, but it still isn't without zinc. You can't use it in European DPF diesels, the ZDDP is still high. VW507 and MB229.52 oils have even less ZDDP than most current gasoline engine oils.

[@robertveeneman9229]

I guess I was either lucky, or covered all the bases correctly when I put a new flat tappet in the sbc of my Monte Carlo two years ago. The biggest things I did was use Brad Penn break-in oil, and I pre-lubed the oil system. I cut an old distributor off, put it in a drill, and spun the oil pump until there was oil coming up through all the rockers. Then started it as soon as I could after put the distributor back in. And brought it up to 2k rpms asap. I had three other guys helping, and we did the carb and timing adjustments while the engine was running. Cam is still good after many miles and many trips through the upper rpm range!

[@dynodon100]

I went to school to teach auto mec. in the 70's and WOW have things changed! Now I tell the kids (as most are as I am in my 90's) use non det. oil with some ZDDP added and so far that has worked.