WHAT MAKES A TURBO CAM A TURBO CAM? HOW MUCH LIFT, DURATION, LSA AND OVERLAP CAN YOU REALLY RUN?

[@bluecollarhotrods9781]

I must thank you again Richard, I'm guilty of worrying about overlap because that's what I was previously lead to believe. I value your experience and knowledge.

[@sHoRtBuSseR]

Haven't watched the video yet, but I'm going to go out on a limb and say it doesn't matter because overlap is only a real concern at idle.

[@markim5087]

Your right , he is wrong and right , if you have too much over lap your just pushing the boosted air into the exhaust , but a boosted motor that’s not a turbo ,a blower makes a difference more than a turbo, ..he is confusing the truth..I’ve been a tech for 30 yrs and yes buikt motors plenty and raced, if there wasn’t a difference comp and others wouldn’t spend millions on tech,

[@exploranator]

GREAT information that can save people many dollars and much frustration! PS the "Baaaaaaah" power sound effect on the motor pic was golden!

[@richardholdener1727]

Boom!

[@burnz3132]

Richard as always your the man!! Your cam game is top shelf for sure!! Thanks for the videos and daily talks!!

[@Jamesrdc]

4:25

[@bcbloc02]

Yes use a good low rpm cam then let the rising boost curve take care of the power on top. That way you can max your power across the rpm range based on what your hard parts can handle.

[@pauljohnson2372]

I sure do appreciate your videos Richard. I'm new to this LS stuff stuff at 53 yrs old.

[@richardholdener1727]

thnx for watching

[@Staypuff777]

Based on Richards advice I chose a "stage 1" turbo cam and a "long runner" stock style intake with my 7875 turbo. I bet the car is way more fun than if I went with a stage 3 cam and short runner sheet metal intake. Most people ignore the advice and just buy cool "race car stuff" and slap together.

[@4myalyssa]

Thanks for all that you do and all of your dyno pulls to back things up.. Your knowledge is very appreciated. To many companies only care about the hp numbers and dont care about the fun of a good street car cam. Then when i question these companies about their recommend cam they shame me if i disagree with them. I tell them, Im old school and love my hot rod with lots of chop. When I tell them that, they tell me 15 pounds of boost and chop dont go together. I disagree.

[@randysullivan5723]

The cam in my turbo LQ4 I got used from a friend who ran it in a Maggie charged LS1. Specs were good for what I wanted didn't care that it was a blower cam . Works great

[@skerlone]

Pressure ratio of exhaust/intake is very important. Everything that he said is true when you have the same backpressure in the exhaust as boost in the intake. That means that the turbine size is most important, as that is what determines the exhaust backpressure. Most oem turbo engines have higher backpressure for better response while most aftermarket turbochargers are bigger and build boost at higher rpm and make more top end power with the expense of lower end rpm.

[@gdaytrees4728]

My wife was inspired by your introductory music. I enjoyed it so much, i played it again and again...and again. Great video, dude

[@richardholdener1727]

Rock on!

[@Musik-h7y]

Very impressive results & impressive work 👏

[@riddler983]

Texas Speed sold me a "Stage 2 blower cam" for my 13 Silverado 5.3L w/P1SC1. 224/228/.600 lift 114 LSA. That was about 5 years ago. Now, that same cam is listed as a Cleetus McFarland Dumpster Fire cam. Their "Boost cams" listed for my truck now are way different.The truck sends 600+ to the wheels so it works!

[@pimpovic2]

There's some mislabeling regarding "boost" cams. Boost should be a generic term, because centrifugal superchargers and turbos like different cam specs. Turbos and positive displacement blowers like a tighter duration spread, like your cam has. Centrifugal blowers (and nitrous) like a wider speed, 10 or 12 degrees. So it's not that your cam won't make power, it's just that for YOUR application a cam with a slightly wider spread would have picked up a bit more if it was spec'd correctly for your blower. Similar to the theme of this video, unless you wildly mess up the boost cam specs you'll make power. But some will make it more efficiently than others. LSA seems to be the common denominator with both turbo and supercharger though. 114-ish seems to be the ideal spot for boost on both. I'd like to see someone cover this point in depth though. With all the talk of LSA on NA cams, and David Vizard even having a formula on finding the right LSA, it's kind of been crickets when it comes to a formula for boost. I'd like to know more.

[@ragtopdeluxezl1]

I rely on chatter of what others are finding out, including you and mostly can get an idea of what parts are working for certain applications. Reputation is a factor as well in picking parts, as you said before BTR was making cams that you thought would test out differently and now you are a believer. I bought from BTR for that reputation.

[@seanb250]

The LSA and duration split absolutely effects the curve, you can see even on your dyno sheet that N/A with the Truck Norris cam the power is holding on all the way to the edge of the sheet, yet boosted the power is starting to drop off and you pull the pin early, its dropping off because there isn't enough blow down time beyond that rpm point to clear the cylinder of the extra combustion gasses, there is only a certain speed the exhaust gas can peak at before it can't move anymore volume, this then becomes pumping losses. If you took that cam and just widened the LSA only then that power drop off point would move further up the rpm rage before you get to the same issue again, then its looking at duration, opening and closing events of the exhaust valve to control cylinder pressures at different points of the rpm range to make sure your not lifting the head and blowing head gaskets or worse all the time. So much more to the science of a camshaft in reference to boost for the best efficiency, performance and longevity.

[@richardholdener1727]

the motor makes peak power at the same rpm, so you are seeing something that is not there-if you want more rpm, cam it accordingly

[@seanb250]

@@richardholdener1727 the boosted engine doesn’t carry the power like the N/A engine, the N/A engine peaks then carries the power like it does because it has run out of cfm but has enough cross sectional area in the intake system to maintain stability. The boosted engine is falling off because of the reasons I said in my original comment. You need to look at what’s happening beyond peak power, if you want that engine to carry the power and replicate the ENTIRE curve then changes to the camshaft need to be made, you should ask Billy Godbold for some advice 👍

[@jarez3781]

On N/A engines tighter lobe separations make more power vs wider lobe separations.

[@richardholdener1727]

IF IT WORKS ON THE NA MOTOR-IT WORKS UNDER BOOST AS SHOWN

[@jarez3781]

@@richardholdener1727 Good vid . Can't get enough of them.

[@bryanmaloney6651]

Not necessarily. Our 500 inch Pro Stock engine ran best with a LSA of 116. The LSA of a cam can give some sign of the shape of the torque curve, but be leery of blanket statements.

[@pmd7771969]

We learned back in the 80s and 90s that there wasn't alot of gain from using a turbo specific or nos specific cam. And only about 20 hp gained from the bigger cams. Bloodviking

[@georgerobartes2008]

Totally agree . Look at turbo/ supercharging as an atmospheric pressure or air weight multiplier . In automotive terms this was thrashed out in 1980s Europe with the introduction of turbocharged 1.5 litre engines to compete with the Cosworth DFV V8 engine . Bhp required to win say 650 . 1.5 litre NA unlimited race engine at 100bhp/litre , 150 + bhp @ 9000 rpm with established reliable cams . X 4 Bar boost = 600bhp with lighter weight advantage made the Renault cars competitive with their 4 cylinder engine at the beginning of the era with mechanical fuel injection . At the end the end of the era cams were limited only by the physical dimensions of the cylinder head or cam carrier space they occupied and fully mapped fuel 8njection , efficient charge cooling and unlimited boost the 1.5 litre V6 engines were making 1200+ bhp @ 11-12 000 rpm in practice allowing the turbocharger to control the boost without a wastegate and anywhere around 850bhp in regulated boost race trim . The BMW iron block 1.5 4 cylinder was making around 1300 bhp in practice with engines and boost levels deliberately designed to last only 4 laps running on the edge of total destruction. On qualifying these engines were removed , retired to the scrap pile after analysis and a race engine installed to actually compete . Rinse and repeat for every race . Totally unsustainable and running out of control . In aeromotive terms this is called normalising . This was thrashed out in the 1940s when both types of supercharging were employed to replace the air weight lost at altitude to preserve the power levels achieved by the air racers at normal sea level , with boosting in war emergency/ take off mode with the introduction of 2 speed superchargers as war and development progressed .

[@Farmtruck62]

I see it as a simple solution. Spec your cam for average power in your desired rpm band for your application.

[@coboscustoms4342]

As turbo cam sales drop like Bank stocks this week.... I'm using the BTR torque cam with the 202/ 202 duration in my twin turbo build. Early Spool, super strong mid-range, no need for over 6,000 RPM. Just look at the n/a power curve and decide which one works best for your application and then imagine it multiplied and that's how you pick your cam.

[@cuzz63]

wont effect sales...Richard has been saying this awhile.

[@coboscustoms4342]

was mostly sarcasm, I've also been saying the same thing for quite a while.

[@cuzz63]

@@coboscustoms4342 cool, sarcasm is hard to tell on text.

[@coboscustoms4342]

@@cuzz63 I know, I mean only the first line was sarcasm. I need to put up a video of my twin turbo truck lol. Look up mrphukyew to find some of my crazy builds

[@richardholdener1727]

I ran a torque cam with a hi Ram on a 4.8 L with a turbo, bad combo, but it works

[@BN-pi3jk]

I sometimes dis agree with your tests, but this I can agree with %100

[@richardholdener1727]

I find it hard to disagree with data

[@austinponceinternational859]

As far as I can tell in the DOHC world the terms “supercharger, turbo cam” compare differently to the “n/a cam” mainly with the event dynamics and not necessarily the lift or duration. The ramp rates being symmetrical vs asymmetrical will make differences too. When they refer to turbo cam is designed to help where the turbo lacks such as down low and opposite with the blower cam. It will help the blower up top when it needs more help. That’s the only thing I can tell that would be different when marketing the terms for the cams. However I completely agree with this for pushrod engines.

[@richardholdener1727]

is the dohc really any different?

[@justin_parks]

In my experience the turbo cams are better on the starting line on a drag strip, with big turbos. Anywhere else you're correct, the turbo multiplies the na power.

[@richardholdener1727]

A CAM 9ANY CAM) THAT OFFERS MORE LOW-SPEED TORQUE WILL BE BETTER ON THE LINE

[@justin_parks]

@@richardholdener1727 I 100% agree with you. I believe the reason there are turbo cams is guys having really rowdy na or nitrous cams, going to turbo and it not spool up. So they call a cam company and say I need a cam that will spool the turbo, bam here's your turbo cam. Edit- I'm also talking about pretty fast race stuff. Couple steps above you're average street/strip car. And the converter along with the tune will make a difference. It's all about your combo and what you want it to do. Just like you said lol

[@jasonmahan6622]

I just recently picked up my Lq4 from machine shop. Went 10 over Manley forged pistons H beam rods, stock crank balanced and polished . 04 gmc seirra street truck. Going 88mm turbo, and not trying to put a big stall converter. What cam , lifters, and injectors would you suggest?

[@jmflournoy386]

When investigating the longevity of 440 Bus engines for Chrysler in the 70s we found that overlap/ exhaust close had a big effect on EGT Stock 440 cam bad and 440 HP cam worse In addition you have to keep the exhaust valve on its seat to cool as much as possible the really long closing ramps killed these motors, exhaust manifolds glowing cherry red on medium pulls and even on our test Cordoba How long do you want to live? changing cam and going to quench pistons lowered EGT 800 degrees That said, as Richard says, start with a cam designed for your usage and torque curve needs then shorter is usually better unless you are really light and short bursts

[@ViewThis.]

I'm building a blower motor, and I chose the old school 327/350hp (.447lift/223dur. 114 lsa) Cam. My thinking is that supposedly blower motors like more duration and LSA, and if that Cam can help a NA motor make more than 1 hp per cubic inch surely it would multiply that even better under boost. I hope I'm right. I don't want to end up building an old slow dog.

[@jasonstormoen]

Procharger and Vortech recommend 112 to 116 LSA. A blower and a Nitrous cam are very similar. I run a 114 LSA with my f3-121 procharger. This video is crazy, just because you add boost to a cam and the power goes up doesn't mean it's right or gonna last. Just like more exh duration than int on a blower setup is what is whats wanted.

[@ViewThis.]

@@jasonstormoen I like to use higher Ratio Rockers on the Exhaust side. It makes me feel good. So does a higher LSA of 114 and your input. Thanks !

[@timweb1510]

Good work Richard

[@buildingracingvideos4714]

N/A engines don't use different cams when running at high and low altitude tracks even though the intake density changes. Why would you change cams just because the altitude changed artificially?

[@b20vtec83]

Simply put, cams no matter the make for what engine will idle,spool and give better low end drive ability with smaller digit specs. But with larger digit specs will teeter-tot the dyno graph upwards in favour of power at the sacrifice of low to mid range torque,spool & response.

[@HioSSilver1999]

Boost is just a extension of na if all is equal.....but try splainin dat to the coyotards and modular guys

[@davidreed6070]

Overlap makes power

[@70_Torino_Guy]

Still learning from your videos, Richard. Good stuff, man.

[@therocket280z7]

Something that's not often tested on this channel is low rpms, where you actually drive the car on rhe street. So, the information is mostly for racing information. What he says is true though, that the turbo is going to magnify the cams NA performance. What you really want for a street driven turbo motor, that is port injected as it should be, is enough LSA so the fuel pressure regulator is properly controlled by engine vacuum. If you put almost any cam with less than 113 LSA on any port injected motor, it's going to buck at light throttle openings from idle up to whatever rpm manifold vacuum becomes adaquate(LSA needs to be higher as lift and duration increase). Even in this case, the Turbo is going to magnify what the cam did without the turbo, as he says. So, the mild bucking it had before will now become violent. Also, it will make more power with the wider LSA at those lower rpms. Which will help reduce the effects of turbo lag. Which you will also really want at low rpms. You don't even have to dyno test to prove that, because it's obvious that the motor that makes 20in of vacuum at a given rpm, is sucking twice as hard as one that's only got 10in of vacuum at the same rpm. So yeah, I wouldn't recommend a 107 lsa cam on your street driven turbo motor...

[@richardholdener1727]

Unfortunately, nothing you said here is accurate. A wider LSA does not make more low speed torque-the opposite is usually true. The less than 113-degree lsa determining bucking with an efi motor is also universally not true. Finally, if you think a 107 lsa doesn't work on a street turbo motor, you need to drive a turbo 5.3l with a BTR Truck Norris or my Low Buck Truck (or any other similar low duration cam) to see how inaccurate the statement is (think valve events).

[@therocket280z7]

@richardholdener1727 I really feel like you just got offended, and wrote a rant here. Try reading what I said again, with the perspective that I'm referring to "low rpms" as idle speeds. I assure you that not having enough vacuum at those rpms is going to negatively affect driveability on a fuel injected engine. Because it affects both the fuel pressure negatively. Of course you can do some tuning to help. But, it's like a band-aid for the real problem. For power, watch your LSA video, and Engine Masters too. They got significantly different results because they used Fuel injection, and they explain how a wider LSA will improve low and high rpm power(flatten the curve), but give up midrange compared to a 107ish lsa cam. Also, you will notice that the FI intake manifold made up for most of the mid-range losses, as compared to your carbed LSA test. I never said the 107 lsa cams wouldn't work. But, I wouldn't recommend one for driving on the street with FI.

[@joekalmar8881]

Howdy great videos all the time can't wait for the next one.! The cad company videos were #1 got a 85 suburban with the pro street heads 4x4 1 ton rears straight cut gears th400 . Anyways what weight/ color springs would you recommend on distributor sbc 383 11 1/2 1 comp xr282 Mickey Thompson cross ram Holly 650s . Runs great but no advance set at 24° really appreciate your awesome work on here.

[@mistermonkey5842]

Bain Racing from Oz, I feel like you and them would make beautiful music together.

[@marcelgrundmann9539]

I run a stage 2 on a 1KZ Toyota LN106 Hilux , over 200 HP. And the extra torque I get is insane... Auckland Camshafts /NZ Call Henry ... he knows the game! Real power just a phone call away!

[@pmd7771969]

It's possible to build an engine that builds loads of tork in real usable vehicle speed. If you can make almost all your power at say 75 mph would be alot of fun. At 5252 rpm at 65 mph could be interesting.

[@n8dawg450r]

So what is the reasoning or claimed benefit for the cam manufacturers to offer turbo cam profiles? Just for the sake of having more part#’s to list in a catalog? Not trying to start a debate, genuinely just asking.

[@TheDrivewayEngineer]

People's minds revolt when you tell them it's as simple as buy the cheapest one that doesn't require more changes than you want to make, i.e. Valvesprings/converters... No no no , this one has a cool name, that one has a cool social media endorsement, this one is custom just for me because my little mass produced engine is different from the hundreds of thousands of others just like it.

[@pmd7771969]

I knew guys who used wrinkle wall tires on the street to hook up all that power.

[@andysteele4056]

I don't think anyone would argue with the statement that adding boost from a turbo will increase power output over not having boost from a turbo. What would be more interesting to see would be to run a group of builds comparing everything from a single pattern narrow lsa cam with lower lift to what colloquially would be called a "turbo cam" with a dual patter, wide lsa, high lift cam and maybe even a reverse pattern cam for funzies, and look at percentage of increase for n/a vs 2psi, 5 psi, 10 psi, etc to see if one makes better use of boost. I get that the variables would be hard to isolate and head characteristics would play a big factor, but I think there would be some themes one could gather from such a comparison. I would think that there is such thing as a cam that operates more effectively with a turbo than others. Would you disagree?

[@richardholdener1727]

IT IS VERY SIMPLE-THE CAM THAT MADE THE MOST POWER NA WOULD DO SO UNDER BOOST

[@pmd7771969]

Most engines are over cammed by home builders thinking more is better. A 3500 plus rpm cam is radical and I've seen street cars with these solid lifter cams.

[@pmd7771969]

You need to decide if you want an engine that makes power and low to mid range rpm or higher range and gear the car accordingly. A 4500 to 8500 rpm cam would need 4.11 to 4.88 gears. While a mid range cam would start out at 3500 rpm.

[@hotrodswoodshed7405]

Fantastic wealth of info you provide to the sport

[@thatturbotruck]

Overlap with a high back pressure in a vehicle will restrict the timing your able to get out of the engine without detonation. I chose a low overlap cam for this reason. If I had twins or a turbo that has a 1:1 back pressure ratio I wouldn't be scared of overlap at all. Even on high back pressure setups I'm not scared of high overlap cams I just know not to get carried away on the timing especially on a pump gas deal.

[@funpeoplearoundtheworld7027]

Still leads to less power especially before the boost ramps up higher than EX bp.

[@jeffb1063]

Richard I have btr stage 4 in my 6.0 with 76mm turbo it’s happy at around 13lbs but when adding more boost it makes less power Data looks perfect Full exhaust 3/12 to 4 inch no muffler Any idea why

[@richardholdener1727]

13 psi with as 76mm turbo on a healthy 6.0L might be out of turbo or at least hot side flow

[@Airman..]

Hello Richard, Please help; can i use BTR .660 dual valve springs with a .656 lift camshaft?

[@BrockwRock]

Hey Richard. Curious if you have any videos of you running that Holdner/Happel “best cam”?

[@richardholdener1727]

that vid is up

[@BrockwRock]

@@richardholdener1727 Thank you for all your hard work!

[@endurovex7272]

how about a 6.0 n/a build combo vid. no power adders. Diff heads and cam combos maybe diff compressions

[@richardholdener1727]

please see the how to max your 6.0l or any of the many other 6.0l cam test videos

[@endurovex7272]

@@richardholdener1727 ive been watching a ton of your vids. I have crank rods and a 6.0 block just looking to do N/A with a manual. Kinda shooting for 650+ hp. no clue on heads or cam

[@endurovex7272]

also thinking e85 with 12:1 compression

[@skeetermcvee4180]

Why did GM make the cam that has 122 LSA for their supercharger. BTW, I agree with you 100% I have a Magnuson Supercharger and the cam is nothing like a *blower* cam.

[@Kstang09]

They have to make the engine idle, operate vac brakes, and run an A/C compressor.

[@b.c4066]

Because gm primary goal is always emissions compliance, cafe standards, making horsepower is the furthest down the list.

[@AdamOpheim]

They made that cam to limit power below 5k because of the type of power adder that was used. They didn't want to make too much power down low and break parts. At least that's what I read and it made sense. I'm sure emissions and all play a factor as well.

[@madmod]

Noise, vibration, and harshness. Nvh limits a ton of vehicles.

[@craig8187]

Driveability, emissions and (think of the difference here from turbo to supercharger) the intake to exhaust pressure differential👍

[@maroonsn95]

So I can run my reverse split TR230 that's a 230/224 on a 111 LSA and this principle would still apply? I love everything about the cam, so if I could turbo it and it would mimick its manners has now, but with more power, I'd be ecstatic.

[@richardholdener1727]

a turbo will multiply what is there

[@maroonsn95]

@richardholdener1727 Thanks my man. I didn't know if it would hold true being reverse split, but thanks for clarifying.👍

[@pmd7771969]

A good gear ratio for your differential would be 3.50 on a streetable car. For top end mostly I'd go with a 320 degree cam and a 3.23 gear with o d. Major top end there.

[@pmd7771969]

A good all around cam for the street would be at about 1800 plus rpm. A radical street cam will be rated at 3500 plus rpm.

[@jakolberamirez8438]

Have you ever done a 4.8 crank and rods in a 6.0 or 6.2? I'm curious if it's possible and what pros and cons it would have.

[@richardholdener1727]

yes-that video is up (I did an ls3 block with 4.8L crank)

[@dallasbristol62]

How long does it take to get oil through the pushrods on a dry LS? I did a cam swap and a few other things I’ve primed the pump and rolled it over but no oil through the push rods.

[@peterbermingham1313]

What I’d like to see was sloppy stage 2 228-232 cam but 108lsa against exactly the same at 114lsa and see what happens NA and boosted

[@richardholdener1727]

the SS2 is 228/230, but whatever the tighter lsa does na-boost just multiplies that new curve as show in the video with every cam tested.

[@peterbermingham1313]

@@richardholdener1727 I understand that, but more of an LSA test then an actual NA to boosted test I suppose is what I meant, just to compare something that’s a definite NA style LSA to something that’s more power adder orientated, possibly is a turbo cam also an NA cam is what I’m trying to get at haha

[@NinjaBoxe]

I would actually like to see that too.. And the comparison of the boost/back pressure curves as well.

[@loafbred]

Your reasoning (and experience) makes sense. The back pressure from a turbo balances the effect of boost during overlap. I'm guessing that a belt driven supercharger is a different story due to the lower back pressure, and would send more raw fuel out of the exhaust at high boost.

[@cuzz63]

I don't think it matters. Blower cams do the same thing. Notice he talks about boost. I believe the difference is the blower comes on stronger at the beginning with no lag.

[@richardholdener1727]

I HAVE YET TO SEE A CAM THAT WORKS NA NOT WORK WITH A BLOWER (OVERLAP IS YOUR FRIEND)

[@pimpovic2]

​@@cuzz63can we please make the distinction between a positive displacement blower and a centrifugal blower? They don't behave the same way. A PD blower will behave just like a turbo. A centrifugal won't, it has a rising boost rate.

[@aaronliddell4280]

So it seems the real question is: Is there anything that makes a cam better for a turbo application than a non- turbocharged application?

[@seanb250]

Yes, controlling cylinder pressures and the blowdown time at certain rpm ranges, this is done with LSA, duration and duration split.

[@pimpovic2]

LSA. There's a reason that most "boost" cams hover around 114.

[@crash5811]

How did u test 5 non-turbo cams? Where did u find them? If all cams r turbo cams? 🤔🤔

[@richardholdener1727]

The 5 cams illustrated were designated turbo cams. The other 35-40 were not designated so

[@albertwaltersjr2480]

Hi richard! Building a 408 with +18cc dished pistons.Looking for a good street cam. car weights around 3,400lbs through a 4apeed auto and 3.73 gears. What would be a good btr cam to go with ? Im all ears !!! Thanks!!

[@richardholdener1727]

a BTR Hot Rod or Red Hot for a daily driver

[@88ranchok]

What about the 2.7 high output Chevy 4 cylinder that has a variable Camshaft 3 different lobes.

[@richardholdener1727]

THAT SHOWS YOU THAT THERE ARE DIFFERENT CAMS FOR DIFFERENT RPM RANGES

[@snivesz32]

If your intake and exhaust pressures are equal then forced induction is just like operating at 10000ft below sea level. But, if your exhaust pressure is higher than intake, as turbos have, then with increased overlap you decrease VE. That changes with rpm, thus your “multiplier” will change by rpm. This is why turbo cams benefit from lower overlap than supercharger cams.

[@superkillr]

[@deemahoney8087]

What kind of camshaft can I run on a Chevy 6.0 with some chop that will still spool up pretty fast?

[@richardholdener1727]

I have some avail

[@MrMrBigro]

Hi Richard I have a couple 2.6 and 2.9 ford v6 and some the Yamaha sho engine how do I select the right cam for these engine? My goal would be more tq from idle and still run smoothly and if possible to make a bit more power is there an equation like you guy use for the v8? Thank

[@richardholdener1727]

there is no equation-you need to see what the existing cam timing is-but cams offer very little power off idle-you need to look elsewhere for low speed torque

[@MrMrBigro]

There rated at 220 hp if I could get it around 240 to 260 that would be awesome

[@dougbrook6223]

Advice please. I have a 5.3 and adding a turbo. Truck norris cam, tbss intake,80lb injectors. Goal of 700hp at crankshaft. My question is maf. What maf is needed. Also i need a vacuum pump to keep my power brakes? Sorry if its a dumb question. Im new to turbos, not new to engine builds. Thanks

[@richardholdener1727]

you don't need a vacuum pump with that cam and most use the stock maf

[@dougbrook6223]

@@richardholdener1727 thank you.

[@Stale_Mahoney]

we need runs all the way down at 1500~2k rpm and there about, unless you run a auto that change every time you get a bit there is a lot of unseen changes i feel

[@richardholdener1727]

1500 rpm at wot?

[@Stale_Mahoney]

@@richardholdener1727 well when it comes to what makes a turbo cam i feel it really should be addressed how early they get on boost not that they simply make boost and power half way down the rpm range. sure for a track car pushing 1k hp drag racing it is not necessary data. i agree wholeheartedly

[@Costar1982]

What's the best cost friendly cam to buy an where can I get it

[@funpeoplearoundtheworld7027]

More overlap leads to reversion before boost, once boost pressure is greater than exhaust back pressure it then does something different. It pushes out fuel in the exhaust and messes with your true cylinder AFR. If that fuel was pooling behind the intake valve some of it is going to go out the exhaust. The wideband will read what the system saw (average), but not what the cylinder saw. So in this case you usually have to add more fuel than normal to get it right in the cylinder, even though the wideband says otherwise.

[@richardholdener1727]

HOW IS FUEL PUSHED OUT THE EXHAUST SIDE WHEN THERE IS MORE BACK PRESSURE THAN BOOST PRESSURE? OVERLAP IS YOUR FRIEND FOR POWER-EVEN UNDER BOOST

[@ferox1183]

@@richardholdener1727 is it the same in a SC config? Actually im looking for a Cam für my SC and in my opinion to much overlap does not work perfectly with SC. Used a stage 2 NA Cam and there was little increase in performance but massive fuel consumption.

[@RC-po3tv]

Hi, Could you please test a MSD wires to check if add some power?

[@richardholdener1727]

they don't

[@RC-po3tv]

@@richardholdener1727 What about the whole system, the coils and everything ??

[@vinnylc]

Love your videos, can you do some tests on the effectiveness of Velocity stacks and or carb spacers effect. I saw a couple videos you touched on about spacers but a dedicated video on these would be great, there are alot of myths in these areas running around with carb guys.

[@TL-re2us]

Will a stage 2 turbo cam with a turbo cause the oil dipstick to come out because of pressure?

[@richardholdener1727]

the cam doesn't matter. If there is excessive blow by-then you can get pressure in the crankcase. If you have boost going from the intake to the valve cover or PVC-same result

[@wcmiller78]

Makes sense. So then why do manufacturers have them categorized as “turbo” and “blower” cams?

[@prevost8686]

$$$

[@croustibat682]

I cant comment on LS engines as we dont have much of them here. While you tested for full throtle, which is ok for drag racing, things may be different when driveability and more boost is factored in. We mostly do high boost DOHC inline 4s here, and high revs NA. The turbo cams usually run "high lift" 10.25mm cams with 270 duration and 30+ psi boost, up to 9000rpm, most power produced with about 115 separation. The NA engines run something between 300 and 330 duration, and rev to 12,000. Pretty sure the turbos would not run great with that much duration, since they cant rev that high.

[@richardholdener1727]

it is makes power up there na-it will do so under boost

[@croustibat682]

@@richardholdener1727 Except boosted cant handle 12,000rpm, so the powerband given by the cams wont be attainable.

[@briandempsey3888]

But what about a RV cam? Or the 3/4" Race cam. 😊

[@GB-gr2yw]

Why not test cams with different dimensions and see the differences then. Example a 215/230@.050 with a 108lsa vs a cam with 215/220(or 215/215) with 108lsa. Then change lsa in same cams and see differences......

[@richardholdener1727]

ALREADY HAVE-IF THE CAM MAKES MORE POWER NA-IT MAKES MORE UNDER BOOST

[@GB-gr2yw]

@@richardholdener1727 so you tested it and did it at different boost/hp levels?

[@Eqium]

Thats exactly what I did I'm building it the way I would build a good NA package and when I'm happy with that then ill pop the Turbo on If I can make 600-700 NA I won't need to push the Turbo, the cam I picked turbo didn't come a consideration. im not building a full on race car im after a tough daily

[@jacobhenry1493]

I love this video, this is what I was thinking and your data confirmed it thank you !

[@Jamesrdc]

4:25 had me looking for someone

[@tjziegler8823]

So if a turbo simply multiplies the N/A torque curve, what does a supercharger do? Does the same concept apply to superchargers, or do superchargers perform better with supercharger cams?

[@richardholdener1727]

Superchargers work in a similarr fashion, but since each blower design also changes the shape of the curve. The PD blower usually requires a short-runner intake and does not provide a consistent boost curve, which changes the curve and the centrifugal blower has a rising boost curve-again, changes the curve.

[@heytonyman]

Why not test it with the power / boost formula in mind? Does a “turbo cam” make the engine any more efficient from a % of gain standpoint versus a non turbo cam at similar boost levels? What about potential backpressure differences at these same levels? I think it would make a good test. Also, what about boost threshold (minimum RPM where the turbo spools)? Or response rate (time it takes to spool at higher RPM)? Might be hard to test on a dyno versus in a car but also be interesting to see if the “turbo cam” changes anything.

[@richardholdener1727]

Did I not make it clear in the video that every cam responded the same (% gain) when we added boost? They did

[@heytonyman]

No actually you never mentioned power / boost formula or showed any % of gain data in any of the examples.

[@richardholdener1727]

To recap the video-boost multiplied the power output of the na combo with any cam based on the formula (one cam did not respond better)

[@jasonstormoen]

​@@heytonymanA lot of bad info in these video.

[@peixinho1973]

Love that shirt ... great vid!

[@pmd7771969]

Some racing cams have a terrible short rpm power band, race only type.

[@petepeto9335]

Soo.. give me example.. 😊 i want 700hp on my 2003 suburban 6.0L.. what mild cam u recommend? And maby what supercharger? Moore charger/cam vids 👍💪💪

[@richardholdener1727]

the blower adds to what is there NA. Choose the cam for how you want it to behave and drive, then add the boost. Lots of blower choices for 700 hp

[@HerpDerply]

MPG - save money on fuel with my 5.7l to buy a turbo kit - what do you suggest for an MPG cam lol

[@nastyvert72]

Are these same scenarios true for centrifugal blowers and PD Blowers?

[@richardholdener1727]

yes-boost just multiplies what is there

[@nastyvert72]

@richardholdener1727 Thank you!

[@rhysavery4669]

so from what i understand from that is when i want to choose a custom ground cam for my forged l36 build to drift with because i want response and mid range power i should choose something in the mild range, would that be correct?

[@richardholdener1727]

yes

[@MrbryanWilson8943]

Hi Richard I’m putting together a stroke 6.0 ls motor with a LSA supercharger trying to come up with a good cam for it need help 🙏🏽

[@richardholdener1727]

BTR Hot Rod

[@DenOfKings]

Im not sure how frequently you check the comment but could you pick a hyundai 5.0 or 4.6. The engines have forged internals and all aluminum block. The only thing there is no tuning available. Could a aem hook up and change throttle body stronger injectors and maybe forced induction

[@richardholdener1727]

a stand alone would fix that

[@teagreen2220]

So basically, for better reliability and a cheaper go fast setup, I should just keep my VVT cam which makes 470 ftlbs minimum from 1800 rpm to 5200 rpm and just turbo this engine? What is my downside here?

[@richardholdener1727]

that works fine-the stock vvt cam doesn't make lots of power in the higher rpm but, the turbo will just elevate what is there

[@simentalg]

The question from a noob now becomes, do I use same valve springs that come with the NA cam or will a turbo make the springs weak and have valve float?

[@richardholdener1727]

the cam you chose will have springs designed for them-use those

[@horsefly1020]

Have you tried the summit turbo ghost cam?

[@tyger13us]

Gotta be FUNNER.

[@turkeyboyjh1]

I have a question, I’m building a budget lq4 6.0 with springs and sloppy stage 2 I got a cat c6 turbo for free from work it’s a 96mm turbine 1.72 ar housing T6 flange and 87 mm inducer and the 110mm exducer on the compressor, I know is going to be lagging as hell but do you guys think it would even be worth it, it’s a brand new name brand turbo it’s going in a 4000lb 4 door th400 3000 stall 3.73 gears and 31” tires

[@richardholdener1727]

try-it was free

[@pmd7771969]

When in doubt go smaller. A fairly stock engine with a 296 cam will suck.

[@ashtonalston2131]

Will a 223/227 .621/600 LSA114 work with a single turbo between 60-65 mm

[@richardholdener1727]

for what size motor and what power level?

[@ashtonalston2131]

@@richardholdener1727 5.3 I want to make between 600-700 hp

[@amcarcs]

Will a truck norris cam in a 6.0 lq4 with t6 vs80 be good? Street car on pump gas. Or mean it wont be the worst cam?

[@richardholdener1727]

It would be good

[@amcarcs]

Awsome, thanx for answering!

[@msmit105]

Dose using a tuber or super charger on the L96 make the VVT pointless? Also what cam would recommend for this application?

[@richardholdener1727]

vvt works with boost too-depends on how much power you want and where you want it

[@msmit105]

@@richardholdener1727 1.Thank you. 2. I'm thinking some where between 500 whp and 550 whp using an 8L90 transmission. 3. I assume it would be some where around 4000rpm or 4500rpm, but really it's which ever RPM rang helps me maximize both acceleration from 55mph to 75mph and fuel efficiency. Any chance we can get videos on the L96? I'm trying to figure out if it's posable to convert an Infinity G37 to four wheel drive so I can daily drive it even in the winter. Which is probably going to be really hard since I have 0 experience as a mechanic, but I figure an 8L90 transmission is a good place to start.

[@LongMoneyRacing]

How about a nitrous cam with 110 lsa and 296/306 duration?

[@richardholdener1727]

does it run na?

[@LongMoneyRacing]

Say no more thanks for getting back to me buddy

[@Costar1982]

Whats the best cam to order

[@Liladelph]

Hey Richard, I got a question about the 5.3L LM4, I was wondering if the Truck Norris Cam from Brian Tooley would work for a torque boost for a daily driver. I am not looking to replace converters or tune it. Any thoughts?

[@richardholdener1727]

a cam swap will require a tune

[@Liladelph]

@@richardholdener1727 great, so my follow up is do I need to find some race corvette guy who will eventually figure it out or is there an out of box tune from BTR that is tried and true that someone can flash on?

[@White.Elemant]

Kinda hard to read the graphs cause the legend color coding is all red... And: the claim "it just multiplies" does not hold true in all of the graphs. The curves are not the same. For sure the boosted graphs are higher, but the paths are not the equal but shifted. The multplier changes.

[@richardholdener1727]

THINK ABOUT WHAT ELSE CHANGED WHEN WE ADDED BOOST FROM THE BLOWER (HINT-INTAKE)

[@White.Elemant]

@@richardholdener1727 whole lotta tubing for sure, If that's what you mean. And along those air that has inertia. Still, claiming simple multiplication is not in all cases exactly what happens.

[@richardholdener1727]

not inlet tubing-intake manifold design as in short runner-simply multiplication is a turbo thing-blower (for the reasons started) are different