This Engine Wont Rev Over 6800 RPM !! Let’s Figure It Out

[@kenmackay9276]

Merry Christmas Mr Morris my teacher , as always teaching this young 60 years young Aussie new information and methods .❤Steve Morris .

[@0097205]

Mad props to a company willing to sacrifice profit to make sure the thing is done right all the way instead of just sending it out to be the customers problem

[@TomJ00769]

True, Mr Morris is pretty smart. He knows great product and customer service will result in more business and profits in the long run.

[@oscaracme]

What's a "mad prop"?

[@FOH3663]

​@@oscaracme Uh, ... mad props = big ups

[@JohnSmith-ps7wp]

He's not sacrificing any profits.

[@amalfi460]

I’m not a real engine builder just an assembler, I wouldn’t criticize anything you do…. There are too many experts in the comment section for that. Keep on being you brother

[@Im_Old_Gregg]

Props to you for knowing the difference between builder and assembler.

[@johncampbell2297]

When I hear people talking about engine builders, you guys are the type of people that come to mind. The people that just put stuff together and ship out engines are just assemblers not builders.

[@veto8792]

Agree 💯

[@D95SI420]

You can tell the sense of honor that Steve has, truly a good dude to the core and exactly who u want to be building your engine. Customer was dead on about anybody else just shipping it too cause they would not put this much effort into sorting every little detail/issue, being a diag guy i was glued to this video cause its such a great example of how to really diag showing how to hone in on the problem along with the process of elimination. Data is so important and always tells the tale though, problem is knowing how to interpret that data and seeing the differences. Great job and excellent customer support :), I am the same way and wont send a job if its not perfect cause customers don't care about the good reviews since they usually just look at the bad. Its not worth a little money to risk your reputation in this industry and being so transparent about everything really helps assure your customers that your looking out for their best interest, most engine builders only care about the money and would never go maximum effort like this for a random customer. Have seen it many times where people try to save money on a engine build taking it to some dude that their friend knows or whatever, the outcome is either they loose the money invested plus all the parts or they actually get a slapped together engine that's never been run/tested. Most of the builders cant even come close to the level of Steve's stuff cause he has all the data from years and knows what works because of it, the guys slapping parts together bought off ebay/amazon thinking they are a pro engine builder just makes me laugh. Have a guy right now that did a stock "rebuild" on a 98 civic D16y8 and after getting it all back together he has a knocking noise lol, funny thing is that's y he was "rebuilding" the engine and he didn't bother to check tolerances or anything and figured he would just slap some std bearings in along with some fresh rings with dingleball hone action. Tried to bring it to me but i wouldn't take it on cause it was all the cheapest Chinese stuff he could get and didn't wanna spend the money at machine shop, the moment he said that i just put the tailgate back up on his dads truck and told him i just cant do it. That's a whole can of worms problem i don't want and its different when the customer has a clue what it takes to actually rebuild a engine properly, money is always the main factor but to do it right always will cost u more unless u have the tools/skills to do it yourself at that level.

[@GhostSniper67]

Steve Morris talking to Mike (customer). Mike, I have good news and bad, good news is we got your engine perfect. The bad news is it took 30 runs and its now time for the 30 run refresh, so it will be another week...😂

[@steveletson6616]

That engine is fine. Steve didn't over rev it. Didn't make it spark knock or detonate. Didn't Lean it out. It did float the valves a number times but that isn't the biggest deal. Valve float is the poor mans rev limiter.

[@danmyers9372]

@@steveletson6616- Do jokes routinely go right over your head?

[@tenzinnorzin65]

@@danmyers9372very well put lol 😂

[@freedomfox8183]

If it was a aluminum rod hemi it damn near would 😂

[@jdubcbr600]

I take it you usually laugh at shitty jokes.

[@cdnaudioguy]

Boost = volume with nowhere to go! kudos for doing it right!

[@ABBperformance]

I really appreciate you giving away years of experience just to help the next one bring another piece of this puzzle for the future ones to improve (bring another piece)

[@bradlink6606]

Merry Christmas!!! You guys are on it. Boost goes up when the valve/'s float causing inefficient air flow overall through the engine, creating "back pressure". Stuff like this is exactly why you are respected by many. Hard tedious work is not cheap, but the results are priceless.

[@89ddx]

On the matter of a solid lifter on a hydraulic camshaft, I have a 383 sbc that we converted around 2 years ago. The engine never really sees more than 6500 rpm and was run for an entire season this past year. The car sees double entry at most events and probably saw around 180-200 runs this season. I had set them during the winter last year, never touched them all year, just checked them a few days ago, and found that they all were still adjusted properly.

[@dallaswiens126]

Fought all these same problems with my bbc, I too put solid roller lifters on my hydraulic roller as well as stronger springs to also solve my problems. Great information and great video.

[@clarkdl19]

Talking about solid lifters, even though this is a completely different use case, The Honda J-series still uses them to this day and the service manuals typically only mention adjusting lash once you hear the valvetrain making excessive noise. I have one that likely has never been adjusted over its 360k mile lifetime.

[@JimN_AustinTx]

I got to 275K miles on a J series till the lash started to become noticeable.

[@EASTSIDERIDER707]

I much prefer to follow builders and tuners as they solve problems and adjust to conditions. Just drop in power and run fast times is less interesting to me. This is like math teachers requiring the student to show the process.

[@sjcottsi]

But then there are a selected few who can do complicated math in their head instantly. How do you show the process there? The equivalent would be a guy that makes changes at the track instinctively and improves performance.

[@scottjamison1602]

This is why I followed you. You are an honest competent engine builder who is worthy of emulation.

[@ChrisRoseberry-r6q]

Steve, great demonstration of valve control and how it can affect the engine performance. Hope you and your family have a Merry Christmas.

[@Bimmer2047]

The fact that it makes more boost psi when it looses control of the valve makes sense seeing that boost is a measurement of restriction and when the valves don’t open all the way there is more restriction in the engine so the boost goes up and the power goes down.

[@2secondslater]

Or is it compression from the cylinders being pumped back into the intake manifold under the supercharger when the intake valves are floating and not seating?

[@g0fvt]

@@2secondslater I don't know but I arrived at the same conclusion. I think inlet valve float may even be allowing some combustion pressure into the inlet manifold.

[@johnhufnagel]

I would hope the valves are opening completely, as I can't see how them not doesn't result in valvetrain damage.

[@onthelake9554]

"losing control" means they are not closing on time . They have no choice but to open .

[@2secondslater]

@g0fvt yeh, it's seems it's pretty much an issue with the hydraulic lifters causing lack of clearance in the valve train at the rpm exhibited and not allowing the intake valves to fully close, it would explain the drop off in power due to less compression charge in the cylinders and the increase in boost due to the compression charge being leaked back to the intake. Either way, we're both on the same page as armchair quarterbacks, there are definitely some weird valvetrain dynamics going on, it was proven by the swap to solid lifters solving the problem.

[@jacquescrusan9500]

At least early on, sounds like The intake valve is bouncing on the seat. That way you're getting pressure feedback into the intake manifold from the force of compression in the cylinder. Assuming that all valve springs are identical across the engine, it would contribute significantly to the manifold pressure increase once valve bounce/valve float starts occuring. Either that or maybe (and take this with a large grain of salt) the exhaust header is becoming a partial restriction at or above 6,800 rpm for the exhaust volumetric flow rate that the engine's producing. Or it could be a combination of both to varying degrees.

[@rustyh8806]

Valve bounce is what I think. People have commented that the valve isn’t opening all the way, because of leak down of the lifter. I can’t imagine this making a bit of difference.

[@georgemanettasmanettas8072]

I have a 430 ci LS with a Harrop 2650, it has 2” primary with a 3” collector. The engine has been built to run to 7500/7800 but it only makes power to 6300 then just plateaus, doesn’t really drop. I have been told my collectors could be restricting a lot of power and not getting exhaust out quick enough.

[@JustinMorrisV82]

@@georgemanettasmanettas8072 How much boost are you running through it. Spring pressure is like fuel pressure. The more boost U need spring pressure. The higher rpm you need valve control . My race engine has 260lb seat it revs 7-7500 all night

[@JustinMorrisV82]

​@@rustyh8806also if springs aren't heavy enough it will blow the valve off the seat aswell

[@georgemanettasmanettas8072]

@ It has made 20lbs of boost The springs are 230 on the seat and 660 open

[@edpetrocelli2633]

I`ve wanted to try putting solid rollers on a hydraulic cam but was afraid to do it for fear of wrecking good parts. About 2 years ago I heard you say that you do it and it`s not a problem. Thats when I started doing it too and the power gains were significant and so was the rpms before nose over. It made sense when you said the cam doesn`t care how stiff the springs are but the lifters do. You were soooo right. My street pump gas motors, air boat and the mud motors get the treatment so to say. No problems to date. User friendly aswell. Your info is spot on and I appreaciate it.

[@JasonHam41]

My guess early on, hydraulic lifter is collapsing at high rpm. Seen something similar on small GM stuff.

[@cruizinmax01]

I'm 5:37 in and my guess is valve float is allowing some combustion pressure back in the intake manifold.

[@cruizinmax01]

After watching the rest of the video and thinking about it, valve float/bounce is what I'd say. The intake valve is not completely closing before the compression stroke starts and the piston is pushing air back in the intake manifold. I'd be curious if you could advance the camshaft to get the intake valve open/closed sooner before the compression stroke starts. Assuming there is enough piston to valve clearance between the exhaust valve and piston. I think this is also proof that overkill sometimes hurts you in the case of the push rods being too large and heavy.

[@TurboJohnRacing]

That is wild seeing the boost increase as the springs start losing valve control. That's great info, thanks for sharing!

[@stevemorrisracing]

No problem bud.

[@rbosley2]

Good job on figuring out the problem and going above and beyond to correct it.

[@brianalbrecht4423]

work'd with a great guy back..ahhh...say.almost 40 years ago...flop'd hydrolic's to solids on a hydrolic cam...cause same basic issue u had...& corrected it...!..as a 20ish yo kid i dident think u could do that...BUT...learned never to question him again...!..as u do...he knew his s**t...he was a "hard" core drag racer/dealer shop forman...i learnd SO much...!..thanks steve 4 all the videos over the past year...healthy & merry christmas to u & family...!

[@mr2cam]

5:41 Pretty easy, boost is a measurement of restriction, when you have a valve hanging up and not opening all the way, that is more restriction, which is why your boost is higher.

[@cruizinmax01]

If a valve was hanging up and "not opening all the way" you'd have broken parts. Rocker, push rod, cam. It's not possible as it's mechanically pushed open by the valvetrain.

[@jeffreyharley1480]

@@cruizinmax01but couldn’t hydraulic lifters collapse and and allow the valves to open all the way? Just thinking…

[@cruizinmax01]

@@jeffreyharley1480 I don't think this is the case here since they shimmed up the springs and it helped the issue some. Then they switched to solid rollers and it helped more but didn't solve completely. It wasn't until putting stiffer springs on the solid lifters that it appears to be resolved. I'd be curious of the weight of the solid rollers vs hydraulic rollers. If the solids were lighter weight that may have impacted the issue more than making the assumption they were collapsing at higher rpm.

[@scottconrad2719]

Loving the search for the root cause of the problem. Thanx for showing us all the extra effort you do. I'll keep buying merchandise to get some coin your way... 😊

[@stevemorrisracing]

Thanks

[@richardmoerke9329]

That’s a lucky man! He is getting what he paid for. Wouldn’t it be nice if more people did this. Like starting with the lifters? Nice job Steve. Thank you for sharing and showing us that people do care about what they do .

[@davidhiggs5670]

Merry Christmas to the entire SM family and crew!!! God Bless all you folks and thank you for the entertainment as well as the education!!!

[@NastyZ28-MY2NDAMD]

Thanks for another great lesson and donation of your time to do so Steve.

[@css0076]

Boost pressure on the back of the intake valve effectively reduces spring pressure. The area of the intake valve (minus the stem) multiplied by boost pressure is the force acting against the spring, reducing its rating.

[@C5Z06CarGuy]

@@css0076 That’s not really true, by the time the valve is closing the cylinder is filled so the pressure gradient is not as high. Forced induction does effectively reduce intake spring pressure, but it’s not as much as you suggest.

[@kacesmithhart5005]

No it doesn't.

[@KenWicks-kp6my]

Boost on the backside of the intake valve is something I never thought about but now that it is mentioned, I can see where that could come into play very interesting thanks guys. Keep up the good work. You’re doing great.

[@scottmuller1901]

As a builder of high 250+ boost on diesel pulling engines , long time ago we figured out boost has little to do with spring pressure needed.. if we were to put enough spring pressure to keep the valves shut at 250psi plus of boost we would need we would need 1200 psi springs just to control the boost, not even taking into account of pressures need just to control the mechanical part of the valve train. 200 on the seat and 7-800 open is all it takes unless your cam is crazy on these diesel engines and the valve train is much heavier than these automotive engines.

[@css0076]

@scottmuller1901.. I imagine the relatively lower RPM of a diesel wouldn't require enough spring handle 7000 RPM either.

[@bobroberts2371]

Two things 1 ) I wonder what the stiffer spring will do to spring osculation at lower RPM ( Spring breakage on other D and D engines ) 2 ) I've pitched the following before but it gets lost in the shuffle. It looks like the dyno room does not have enough make up air from outside of the entire building. ( RE it might not be just the dyno room not getting enough air flow, it might be the entire building isn't getting enough air from outside. ) Look at time 900 and 1641. The left hand exhaust fan slows down and the shutters get pulled shut at high RPM. When the throttle is dropped, you can see the lexan window spring back. A quick test is to make a U tube Manometer from clear plastic tubing / colored water or hook up with a HVAC guy and use their differential pressure gage ( Generically Dwyer Gauge ) While this isn't related to the lifter / spring / HP spike issue, it is going to present a restriction to the intake and have the effect of a restrictive air filter. Given the boost sensor is referenced to ambient air, a lower pressure in the dyno room is going to make measures pressure a bit higher. ( Maybe 1/2 LB ? ) This effect is very evident on larger engines moving lots of air.

[@robertmason8341]

Killer eye, this comment needs to get more attention! I’ve noticed the Dyno rooms get more sophisticated and more attention is paid to things like making sure the engine doesn’t suck the room dry so to say when you go up the line in order of the small guys to the real big guys like Gale Banks who is approaching oem level with his setup.

[@bobroberts2371]

@@robertmason8341 Thanks Gale Banks can do EPA validation testing. He also does stuff for the military. He isn't a yahoo that just throws fuel at a diesel thinking that smoke = power.

[@robertmason8341]

@ exactly that’s why I mentioned him in particular. I watch all his stuff, best in his industry IMO. Hey do you know any channels with guys that do naturally aspirated stuff. Trying to find some good cylinders head content. I enjoy watching Steve’s stuff cause he’s a great guy, but I’m an all motor plus nitrous motorcycle drag racer. We need the cylinder head to make power before we put any spray to it!

[@bobroberts2371]

@@robertmason8341 Powell machine and Eric Weingard ( I think the spelling is correct ) Seem to be doing NA automotive stuff that could relate to MC stuff. I'd think that high RPM bike stuff would be very different due to high port velocities leading to choked flow sooner than automotive stuff.

[@robertmason8341]

@ I watch both of them, know any others ? I don’t think there’s any bike specific engine builders but i can still sometimes catch a nugget of useful info here and there from car guys plus I’m thinking of building a drag car, I’m getting a little too old to be going 180+mph

[@jameshenson4871]

Steve i am so glad you mentioned about the lash adjustment on a solid roller. I have ran them on the street for years, check them on the oil change and they are usually correct. When Idecided to run a solid roller on the street everyone said I was crazy. Solid roller are the best.

[@kylemilligan752]

Hydraulic lifter Hp trend improved with more valvespring pressure. A bad/squishy/leaky hyd lifter would normally be pissed off with more spring pressure. I'll bet the cam lobe/spring pressure combination is allowing some valve bounce on closing, and the hyd lifter took up the slack. Got better with solid lifters because they cant pump up when you have seat bounce on closing. Improved again with solids and more valvespring pressure to combat valve closing bounce. A milder/slower cam lobe might make the hyd setup happier and require less spring and more rpm? Honestly, im just throwing out some ideas, not trying to detract from the video. This was a great problem solving video, paying attention/analyzing the data, and approaching the problem in a scientific method. Thank You Sir!!!

[@rickbrandt9559]

"Best Holiday Present" -- Miles of SME Smiles opening to video

[@marianoleonel8914]

I love this channel... I saw a ton of good channel about engine on youtube, but SM is one of my favorite with any doubt. It would be a dream living in the US and working as an engine builder! The american are the best, I read a ton of cartech books, see a ton of videos of SM, Darrin Morgan, EFI university, total seal, etc etc, and learn a lot! So I really appreciate the people who take the time to share information, and make good content, for people like me who can't really do that kind of cool stuff. Merry Christmas from Buenos Aires, Argentina, and thanks

[@MsKatjie]

Yes I agree. Cheers.

[@jimdrummondsr6467]

I'm glad you posted this video. You may have helped me solve a big boost surge problem . 75 mm torqstorm puts out 12 lbs of boost up to 6,500 RPMs. From there it rises to 21 lbs @ 7,000 RPMs.

[@brianholcomb6499]

I’m only at 7mins or so! Anytime we ever seen boost jump like that, an intake valve, or two was not opening! Like regular travel lifters, bottoming out! LS7 lifters have been garbage lately! Take some apart & see the beautiful machine work, & trash in them! They all quit right around 6800, unless you actually get a good set! Some guys run 8800, season after season with a really good short travel hydraulics! To the lash babies, ask guys that have owned there tractor trailer trucks for decades! It’s called running the overhead! Most of the super experts, get super anal about adjusting the valves! Even at 150000miles, they are all usually within a few thousands! Other than brand new rebuild, or something going away! Merry Christmas 🎄🎄🎄🎄!

[@ZOTTISHIGHPERFORMANCE]

I believe the boost went up when the intake valves bounced off the seat letting the cylinder compression pressure return to the intake. BTW You Guys do great videos with great information. Greetings from Brazil 💪🏻🏁

[@93_LXcpe]

My guess also. Beat me to it

[@jtrill2]

After reading your thoughts on what is happening i was considering it as a possibility but since the intake closes after bdc if the valve bounced it would just effectively increase the duration of the intake closing. It would delay the closing so much it wouldnt gain cylinder fill anymore for compression bc the piston is up too far now thus compressing less air, leading to lower power but i dont believe the intake side would show more boost as like i said the intake already closes after bdc. Im definitely not arguing right or wrong. Im only engaging in discussion bc its interesting and a fun challenge to think about. I hope to always learn and dont care if im right, i do seek to know what is actually happening. Thank you for posting your thoughts on the engine.

[@dennisjensen7938]

Steve you and your team out did yourself again! This is the major reason I watch your channel...Mike is 1000% right when he said no other engine builder wouldn't take the time to figure out what was wrong..

[@stevemorrisracing]

Thanks

[@Shademax4273]

Customer:"Cool man that"ll be perfect!" Steve: "Ok Yeah can t do that."😂 Gotta commend you for always trying to do the right thing.👍

[@stevemorrisracing]

Thanks

[@glenbrannon7224]

Very good lesson this shows what happens when the lifters are collapsing and that the springs can't control the valve even on a Mild lobe profiles cam. Also I ve seeing a hydraulic lifters problem across all the manufacturers. Thanks again Steve .

[@stevemorrisracing]

Yep

[@sailinwrench]

I've wrenched professionally for over 30 years on everything from chainsaws to tractor trailers, and I'm still learning. Especially when I watch your channel, thank you, sir!

[@lobo7107]

New to your channel but I can’t already see your attention to detail is superb! If I had an engine to get tested it would be yours to test. I appreciate your demeanor, you have my vote!

[@timothyrunner66s84]

Merry Christmas Steve and Family and crew.

[@Jeffsa12]

A big TY Steve! Sharing this info is invaluable for the everyday enthusiast that would never have the resources to chase an issue like this down to the root cause. I have to ask now though, in your opinion how many HP would be on the table to replace the hyd roller cam profile for a dedicated solid that had lobes designed to be easy on the valve train? My guess based on nothing is possibly twenty HP. I can't see the cost of changing the cam being worth it though. Being an old school racer from the 1990's, I don't get why it's so common for LS engines at this level (7000+ RPM) to use a hydraulic lifter.... In my days, if it's going to RPM much past 6000, just go solid lifter. Hydraulics just make no sense to me at this level everything taken into consideration.

[@BF26595]

As a disclaimer, I have never been to an engine dynamometer session, nor am I particularly literate about engines and their inner workings. An interpretation of boost pressure, is correlated to intake restrictions. I can have an engine running 20 psi of boost with bad heads and/or not enough valve train to flow the air required, and I can have the same engine, making the same amount of power on less boost with better heads and/or a better valve train setup. This is the same reason why an intercooler works wonders, because by cooling the intake charge, you bring up the density of air; when the air is denser, it takes less volume, and with less volume, the pressure is lower while making the same power. There is a great video from Engine Masters on "Motortrend" explaining this very fact with tests on the dynamometer. This being said, a sudden increase in boost from a compressor like the one on this engine, driver by the crank which increases rotational speed linearly with engine rpm, can only mean that the restriction in the intake has suddenly increased. This can be due to a few factors, like Steve listed in the video: 1. The valve springs cannot control the valves at that rpm, I would presume the intake valves are the culprits since they are larger and therefore heavier. 2. The original lifters (hydraulic) were collapsing, not having time to refill the hydraulic plunger, therefore lowering effective lift at the valve.

[@crossboltmains]

Brother wrestled with engine high -RPM trouble, years ago, after stuffing a popular brand cam in his SBC. . Thanks for showing what the engine dyno helps reveal to the experienced tester.

[@ryanfuhr8704]

Good stuff here. Thank you for sharing the details AND dead ends you investigated. As you noted, a boost spike like that, in a PD blower (which has no blow off valve equivalent) must necessarily mean the engine "resistance to flow" increased. The only way that can happen as a function of RPM is a valvetrain problem.

[@Patricks_Projects]

Wild guess at 12 minutes, valve float. The intakes are hanging open, and the cylinders are pumping back it´s air into the plenum, making the boost higher.

[@EddNoll]

Merry Christmas. Learned more from you in the last year it compares to all my years in tech school on the mid 80s put together. Been in the field ever since.

[@seanp777]

Thanks for all the knowledge, just a garage mechanic and love to learn new things. Maybe one day I really work on modding my engine.

[@konjiki240sx]

I've had good results with my line2line coated oil pump. It basically self clearance once installed on the engine and pressure increased through rpm range. Some of the typical coyote noise went away too. I can't wait to see my oil analysis results to see if engines wear pattern has changed. (This is on an N/A street car) Its going to be interesting to see how it fairs on a higher hp build. I may try it on my road race car and see how it holds up.

[@neilvenners3309]

It’s nearly 11am on Christmas Day here 🇬🇧 but I had to watch your video Steve! Now I’m rushing 😂 I wanted to wish you and all the Morris family a very Merry Christmas 🎄🎁🥂🍾❤️

[@ronomark497-nk9ve]

You just gained another customer by your never quit/make it right ethic. Someday, when I need a motor built, no question who will build it. Merry Christmas!

[@Zedsdead83]

Thanks for the year full of top notch dyno and racing footage Steve and Team. Appreciate it. You guys are the best🔥🔥🔥🔥🔥🔥🔥🔥🔥🇺🇸🇺🇸🇺🇸🇺🇸🇺🇸🇺🇸🇺🇸🇺🇸🦅🦅🦅🦅🦅🦅🦅🦅

[@Sam-sg3gb]

Enjoyed the problem solving process! Please enjoy the time off with your family in celebration of Christmas.

[@lowbudgetbob1155]

Most engine builders probably don't have the conscience that you do plus your dedication to your craft is above and beyond anyone else. You put product over profit... Using solid lifters on a hydraulic cam was done on Engine Masters with really good results, that's the first time I ever heard of that. Could this be the wave of the future? You eliminate hydraulic lifter problems and from the sound of it, valve clearance maintenance isn't an issue.

[@Scubasteve22]

If this was a turbo engine, it would have lost boost when the spring/lifter was no longer happy. But since its tied to the crankshaft, the boost is able to bounce the valve a little higher and gain more boost... As far as the lifter deal, if it doesn't say Johnson on it , I dont put it in my customers engine....Just never any drama...Thanks Steve and Kyle for sharing.

[@alanwparkerap]

I had the same issue with those lifters. Ordered ls7 performance gm lifters and had a bad tick from day one. Went to Johnson lifters and runs perfect.

[@frankensteincreations4740]

Best thing about boost is it’s nothing but a measurement, and a tool. When there’s a change in “boost” like this, it’s always going to be something mechanical. The ol lifters just aren’t up for the task, at that specific rpm, and cylinder pressure. Primarily the exhaust side… found the limit of the Ls7’s lol Love how you guys don’t quit, until it’s right. Exactly how I do stuff. 👍🏻✊🏻👏🏻🤘🏻

[@bluethunder-nd6to]

Very good info. I have an engine that dies off @ 6400. Eager to apply gained knowledge to see results

[@mitchellsprowls9413]

Merry Christmas to you and your family. I see Dewey in the background looking for his present's.

[@Nordmende01]

My suspicion after seeing that the pressure suddenly increases at 6800 rpm is. That the valves are no longer opened as wide. If hydraulic lifters are installed there, the oil could be pressed out of them. The valve opens less as a result. I'm curious to see what it is. On the camshaft with solid lifters. I can only imagine that they could be hardened differently. The hydraulic lifters act as dampers. The solid lifters do not offer this. The surface of the cams is loaded differently. I cannot judge whether this has a negative effect.

[@jasoncole1759]

you are the man Steve...figuring the stuff out and making it right for the customer at your expense!!!!! Marry Christmas and god bless you and your family!!!!!! have been watching you since day one....

[@theoldbigmoose]

Blessed Christmas men! Learned a lot in today's video. Thanks

[@lucascb750]

Pressure is the inverse of flow... I also do not understand the fear of solid lifters. You may have to adjust them once after the valves seat in, in a set of new or newly machined heads. The first pulling truck motor I built taught me that, for 6 seasons of pulling, it only needed an adjustment once. Other then that there was no significant change.

[@JakStoll]

boost going up I would think of as a sudden loss of VE so to speak or flow on the part of the engine .. basically losing control of the valve train ... IDK if the valves are bigger/heavier in this case than previous combos you have run with these lifters ?? I am not an engine builder.. Ive assembled them my whole life Im 57, I honestly would have backed the lifters off to 0 lash or + 1/8 turn before changing them as a quick diag check... I am a tuner and fabricator and I dont quote fabrication work I bill hourly, time and materials, I do communicate clearly with customers on a daily basis... I think its admirable that you are willing to eat labor to make sure things are right.. and if its something you built by all means its the thing to do.. if someone brings you a weird combo or like what I do for a living, square peg in round hole .. communicate clearly what the issues are and that it takes time to solve them.. time costs money

[@jasonalper7898]

On our Sand Car Motors, we run a Johnson Lifter setup at .040 preload with a PAC 1209x this gets us around 189lbs on the nose and Johnson wants it 520lbs over the nose on a 660 lift camshaft.

[@69L88]

I feel your pain, the road to discovery is expensive. Eight years ago I had a 400SBC, fixed oil pump, for correct volume and pressure, hydraulic roller lifters, to solid lifters, back to different hydraulic rollers, ti retainers, valve springs etc. GOOD JOB. PS sorry about your dyno, hope SF, takes care of you.

[@mr.jitters6531]

I love watching Steve's brain at work. That thing never stops until it's satisfied!

[@Mark_Spivey]

My swag was that it was spring related. I never would have thought to put solids in to test. That’s why you’re the pro.

[@jtrill2]

Supercharged boost of course increases as a function of rpm, but because the valvetrain isnt keeping up, the flow isnt there and boost pressure rises. Furthermore since an engine is an air pump and normally creates suction in the intake. When the vavletrain is not keeping up, the supercharger boost will look like its increasing bc the vacuum of the engine has been reduced and more than likely its exhausting efficiency is lost as well.

[@racervx54]

We Adjust the lifter lash 1 a year on our 581 1060hp bracket motor. Been doing it that way for 25 years.

[@sidswift4709]

It's lost Control of the valve train somewhere

[@supertunesupertune]

Been doing solid roller lifers on hydraulic cams for some years now at our race engine shop, dyno told us almost the same thing but running as n/a setup. Good for you to push the real world results!🤩

[@stevemorrisracing]

Thanks

[@AnonAnon-e7r]

I had a 302 in a Fox body back in the day with solid rollers, daily drove that sucker drove it to Mid Michigan Motorplex from Grand Rapids raced it and drove it back with zero issues.

[@mwall1296]

Turn smoothing down and valve train issues are easy to see and find. The line gets jagged as you loose valvetrain control. Use individual O2s and valve train issues are easy to see and find.

[@sk8shackcrew]

Hi Steve, great video! I agree with css0076, I too have seen compound turbos on tractor pullers hold valves open: not the case here. The lifters were partially collapsing at high RPM thus not opening the valves all the way as evidenced by the climb in intake pressure not having anywhere to go. Keep up the good work!

[@builtnotboughtgarage3762]

awesome again and very interesting. Wow thats crappy youtube views are down, I am going too watch it a few times to help out

[@rickrack78]

On tuneup stuff we used to drop a cylinder spark or fuel and look for rpm drop and/or look at coil voltage on each spark plug for how much voltage it took to fire it. It’s been around 40 years since I tested engine on for a job so I’m digging a bit into my memory

[@thatlangley0715]

I am still trying to understand the gain of boost with the loss of HP. Is the boost gain being caused by the exhaust valves not closing properly and leaking, which causes the boost to elevate, and the HP is dropping off because it's not staying sealed totally during the combustion cycle? Otherwise, a totally amazing explanation of everything and shows your attention to detail and willingness to go that extra mile to prove/disprove a theory.

[@stevemustaikis6602]

Another very informative video, heck in fact you even learned something. Merry Christmas to you, your family and crew.

[@MAXPOWERRACING]

Boost is a measurement of restriction . As the valves begin to float air cannot efficiently move through the engine which in this case causes the boost to go up at the same time the power begins to fall of the cliff

[@larrypeck214]

Thanks for the videos. I learn something new each and every time. I am new to the LS engine and I appreciated this particular video very much. I also have an LSX 427 with the Magnuson blower set up. Thanks again! Lookin forward to my first drag n drive in approx a year and a half from now.

[@matthewmccormick2417]

Merry Christmas Steve, Val, Kyle and the SME Gang. Top notch tec from Steve and crew. Ohh last cookie "Eats 20 more" LOL

[@StanleyHarris-d6l]

Great video!!! No engine builder on the planet would do all that at no charge other than you!!!! Merry Christmas

[@4familyman]

Nah, most know to use Johnston short travel lifters for a higher revving, boosted LS instead of wearing out a motor on dyno.

[@chrisrogers5644]

Abratable coating great concept. any clearance set up except for valve lash is a static clearance meaning non-running engine. when engines run you have unique heat/pressures etc that are slightly unique to each engine. abratable coating is custom dynamic clearance not static clearance for each particular engine. love the idea and I expect it to show better performance and less wear and be much more widespread in the future

[@Charlie_boards]

Props to you guys for always doing the right thing even when it isn't necessarily profitable. Question though, do you guys look at exhaust backpressure on the dyno? Usually you're looking for a restriction, but in this case, I think you may have seen a dip down in EBP that correlated with the boost increase at that 6800rpm mark.

[@scottknappen1952]

Merry Christmas from one long roof lover to another!

[@mattchew7219]

Great video Steve, troubleshooting a valve train really takes a trained eye. Warning I learned something!! Pretty cool watching this from beginning to end.

[@truegret7778]

Fascinating. Your thirst for more knowledge is inspiring. Hey, Merry Christmas !! Here is to a safe, sane, prosperous New Year for Steve Morris Engines. Thanks for the pro-tips.

[@br549rdr]

This is what KZbin was made for. Educate the people. Thank you professor Morris 💪

[@planesofpaper]

Learned heaps. The boost going up made sense when you list control of the valve. Merry Christmas to you all the way from NZ in summer.

[@georgemanettasmanettas8072]

Steve on a blown engine that has been built to run to 7500/7800 , could exhaust restrict the power. Engine only makes power to 6300, it can still rev further but doesn’t make anymore power. I have been told that the collector size would do this.

[@MsLoneWolf4]

being a valvetrain issue at high rpm, the intake valve is not closing fast enough . All the air and fuel of course being spit back though into the intake manifold where I'll bet that you are measuring boost pressure trapped by the blower like you showed in the pump video. and due the cylinder still some compression it is adding pressure as well just like an air compressor needing to build pressure to push the air already inside your tires in order to raise the pressure in them. which why the boost value is drastically jumps up. Of course I may be wrong as I am basing this theory on a N/A single cylinder air cooled carbed engine with the intake valve stuck open with soil contaminated oil; where everything it sucked in got spit back out. which isnt a bad way to get a free riding mower. now as my theory to why it is happening on this engine is the lifter is losing contact of the lobe leaving the spring to play catchup to the cam which where the hydrualic was worst because once it finally caught up to cam the spring had to compress the oil filled lifter back to normal by then its too late the cylinder is already 10% or so less filled in turn has less energy during combustion. the solid lifter eliminated the time for oil compression after catching the cam and the higher spring rate made it harder for lifter to leave the cam lobe.

[@Normalguy06]

Merry Christmas Steve. Thanks for all the content, knowledge, and inspiration.

[@AndreenMotorsports]

If the boost jumps, it's because the air is all of a sudden backing up in the intake, which means its collapsing lifters. If the lifters are collapsing, they either dont have enough oil pressure up top or its something wrong with the lifter itself that isn't allowing them to maintain enough pressure. I doubt its unshrouding at the wheel because I would think you would start to see the issue more in the 5500rpm area. What does the oil pressure curve look like? Can you put the oil pressure sensor in the top anywhere? It may be cavitation in the pump, pulling the pan dry, kicking the pressure spring, etc. Just to be clear, the problem was never fixed. Changing to solid roller lifters is just a band-aid. You still have no idea why the lifters were collapsing.

[@arthurrodesiler3109]

Learned long time ago if you want to make power use a solid lifter cam. Crazy things happen with a hydraulic lifters. If you keep the max oil pressure below 40psi hydraulic lifters seem to work better. For some reason hydraulic lifters seem to pump up at different times. BBC is the worse because of the angles. A straight line like a small block chevy pushrod works the best with a hydraulic lifters. Had a hydraulic lifters sb chevy cam with a red line of 7,000 rpm and would pull hard to 8,000 rpm. We had a BBC with a hydraulic lifters and it was a 7,000 rpm cam and it would break up at 4,500 rpm with a 70 pound pump psi. Put a stock 40 pound pump and it sometimes would pull to 7,500 rpm other times it would break up at 3,500 in second gear only on a 400 trans. 1st and 3rd gear it would pull to 7,500 rpm. Drove me crazy as I tried everything I could think of which was a ton of work with the engine in the car. Finally took the hydraulic lifters put in solid lifters and 7,500 rpm all day long. A lesson I will never forget to the day I die.

[@stewarth8390]

Great video and I enjoy how you go into detail with problems then actually talk about possible causes etc. I’m not a builder either, I’m only just tearing down my 377 sbc street strip engine now after a solid roller lifter cried enough and broke, sending the roller and needles off on a pinball journey through the engine. With that LS and the boost going up like it did, is it because of some valve float creating back pressure behind the inlets causing the boost to rise in the blower and manifold?

[@tomroe7715]

I had a ls that had a Paxton on it and at high rim the valves would float just a little. It barley burped in the exhaust is the way I caught it. For some reason the boost will build up and back pressure cause it cannot move the air properly. Learned that on huge compressors on the oilfield.

[@fmerkl]

Merry Christmas Steve & Kyle ! Love your vids!