Speed Secrets: Is A Bigger Cam Always Better?

[@Compcams1976]

Let us know what you want to see next!

[@Uncle_Chuck]

COMP Cams hi mate I’m keen to know how the figures overlap, As if you lined these three cam configuration in three identical cars identical drivelines i.e gear box & diff Where does the torque stop and the horsepower take over And over a distance say quarter mile times It be an interesting video Also I’ve messaged many times asking about a video you made about the edelbrock top end kit for the ford Windsor I cannot seem to find it anywhere

[@Compcams1976]

@@Uncle_Chuck If you look at the graph at 2:48 you can see a good diagram of how grind of a cam affects power. Usually the "meeting point" is right around peak torque (seen here at 5000RPM). For a comparison to real life, that green line (XR265HR) would feel more powerful up until that changeover. Therefore, if you have a daily driver that really never gets beat on, or it's a heavy vehicle/does a lot of towing, the "less aggressive" grind is actually the much better choice. However, above 5000rpm, you can see the tradeoff you have in top end power. If you're looking to make a street/strip car, that low end doesn't matter nearly as much, so you'd focus on the top end power, where the XER281HR makes considerably more power. With the correct converter, you'd pick up a couple tenths more than likely, going from the 265 to the 281.

[@Uncle_Chuck]

COMP Cams and the video You made a few years ago on the edelbrock top end kit for Windsor? I can’t find it anywhere was it deleted?

[@moh97gt]

3 cams same duration but different lsa , 112 vs 115 vs 118 LSA

[@Compcams1976]

@@moh97gt Good idea! We get a lot of questions about how Lobe separation angle changes the power curve.

[@artlife6210]

just finished installing my new ATK 5.3 into my 98 Trans Am and installed the 265 cam used here in it...the car has a huge increase in torque and horsepower over the stock LS1, and great vacuum with a nice lope at idle..Comp Cams did their homework on this one and theres really no need for a bigger cam unless I upgrade a lot of stuff to keep up with it, which means more money and less driveability around town..Ill keep my 265 cam, and enjoy a fun ride with total driveability..

[@jaygooch1190]

I would love to see a test on thermal and friction coatings on bearings, pistons, chambers, everything

[@AirsoftHemi]

So they lost 16lb of low-end torque to gain 41 horsepower. I think that's worth the trade

[@zAvAvAz]

i add both horsepower and torque together map it across the rpm band, then use that as the basis for all gearing, stall, weight, shift points and rpm limits. Street machine tuned. use a th400 with 2.10 first gear, 1.40 second gear, 1:1 third gear. and 3.90 gears. 500 torque 388c.i.

[@jerryrojas5175]

Hey Richard Have you ever tested a Lunati stage 4 Black Magic cam on a 6.0L?

[@oceanwaves83]

To me, while large cams sound the best and are the best for racing, it's more fun to drive something with big torque down low and a stock or near-stock converter. Daily driving something with a 4k stall isn't very fun. Especially when you can't get it to lock in city traffic and your trans keeps wanting to heat up.

[@johnallen7230]

Richard Holdener does an excellent job

[@sportsmansparadice42]

Me personally if I'm going to use a cam the big I would bump up the static compression ratio. The longer the duration the more it leaks down at low engine speed thus giving away torque. Most would agreed Torque rules on the streets.

[@mrat455]

And Almost everyone over cams their engines because they want the sound. Street engine build one with the most torque you can get between 2500-4500.

[@Freebaggin]

G'Day from Adelaide, down under. Love this series however I notice you never feature the Thumpr series. I have seen many a back to back dyno shootouts with the tighter LSA cams being the clear winner. Can you please as Richard to test LSAs back to back, as I see he seems to have a preference for wide LSAs without necessarily explaing why. Cheers, Lachlan.

[@Compcams1976]

Good point! This gives us a few different ideas for videos!

[@tylerbateson9553]

Cant hear any audio. Sucks because I like watching these at work, usually super informational and awesome videos to listen to. Thank you guys for all the knowledge

[@Compcams1976]

Unfortunately some of these videos only seem to come out of the right speaker, we're working on fixing it.

[@tylerbateson9553]

That explains it, I'm on a cellphone with 1 speaker so it must default to left. I'll check it out when I'm home, thanks for the heads up!

[@dxracing99]

COMPRESSION ratio vs duration?

[@victorboyd4052]

Question is there a video of you doing this same test on 5.3

[@thruitallauto2538]

I have a 350 Chevy carb motor. I would like a cam with some lope to it with out having to change a lot.what cam would do that

[@Compcams1976]

Give us a call at 800-999-0853 and we can get you a perfect recommendation!

[@rossgirdeen3247]

I found a cam cs 108r cam was out of a small block ford. Good shape looking to reuse it on a new engine. Is this cam good for a street engine?

[@thomasmcgee3766]

I'd like a little better understanding of the "highest hp" cams either have high lift low duration numbers and some have less lift but more duration. Like How does that change the power curve? Is there a benefit to one over the other? Etc

[@petejoseph8257]

Excellent info here, Richard.

[@silverbackanimal7215]

Can you get better fuel economy from a bigger cam ? But have that power when you want it??

[@enriqueacosta875]

Hello Richard. Love your videos. I have an observation and question? All three cams made peak TQ at 4900 RPM and peak HP varied from 5900 on the small cam to 6300 on the large cam a difference of 400 RPM. Looking at idle quality difference from a 115 cam to a 112 cam, where exactly is the extra power coming from? I ask out of ignorance. At what lift are these heads flow peaking at or does it matter? I am wondering how a cam with the small cam LSA of 115 a mid cam Lift of 566/568 and a large cam duration of 232/234 would perform for street hot rod, no racing! ;o) Thanks Richard, again love your videos and the presentation.

[@turboscotty250]

I'm building the same lm7 with the 54-454-11 cam with the 26918-16 springs. What push rods should I run or can I run the factory?. Thanks

[@olderthanyoucali8512]

I'm curious,? You received a degree in Advertising, how did you get into building your first performance engine and where does the financing come from for all the builds and dyno time.?

[@dannymccarty344]

Being born into a wealthy family, of course.

[@moh97gt]

negative vs positive overlap

[@littlevman2997]

All that low end torque could be redeemed with compression

[@oscarcuevassn95saleemzr12]

Best cam to awake a v6 .

[@mrat455]

You need to match cam with what you want to do and where the engine will speed most of its time. Also take average hp and tq between 2 and 6K and see what it shows. Most the time for a street car smaller is better, build it for max torque not hp.

[@Nak3dPirat3]

BUDGET SMALL BLOCK CHEVY CARB, CAM, AND VORTEC HEADS BUILD

[@richwahneEXPERTSmadeEasy]

I will NEVER purchase a Comp Cam again in my lifetime!!!!!

[@fernandocarreon2188]

I have a very very big cam and my spark plugs keep burning every month do I need to buy better heads btw my camshaft duration is over 250

[@ScreamNoFear]

This’s tuning issues

[@cammontreuil7509]

Lower heat range plugs.

[@gloriamaletta8667]

First you want a cam that will work with your cylinder heads and how well they flow putting in a monster cam that surpasses the flow of the heads being used is useless plus stall speed gearing weight of vehicle intended use and rpm range can change to get the absolute right choice for a camshaft your ideal cam will give you good numbers in horsepower and torque throughout the entire rpm range starting were your stall converter stops slipping you'll go faster if your more interested in power throughout the entire power band than just peak numbers at any single point in rpm range but peak numbers sound great many times something with say 10 or 15 less peak horsepower at peak can make 20 to 30 more horsepower or torque in the mid to upper mid range say 3800rpm to 4800rpm that may be more than worth the 10 or 15 horsepower at peak the wider the power band is the better you want something that makes power as soon as possible in the rpm range and pulls well with the least torque loss at high rpm or redline and of course finding that happy medium is not easy

[@josephpinheiro9667]

why does the engine lose torque down low when it's getting more air compared to using a smaller cam lobe?

[@lazarorivera3384]

joseph pinheiro good question

[@TonaldDrump686]

My guess is the late intake valve closing. Good for top end but not for low speed.

[@johnkraft7461]

@@TonaldDrump686 Other way around - long duration exhaust and overlap gives the reduced vacuum and compression at low revs so motor can't develop torque. A fair amount of the charge is going out the exhaust. Stand behind a big-cammed car at idle and you can smell unburnt fuel in the exhaust.

[@homadu1830]

So what if your rpm is very slow

[@javilsx363]

Hey richard have you tested cams like the comp 235/251 with big splits on ls3 or ls7

[@TonaldDrump686]

Just an opinion, but I think the modern heads don’t need the big split like early heads. Exhaust flow should be 75% of intake flow. Early heads with shit flow and a single pattern cam leave much to be desired. Old timers said exhaust valve should be 75% of intake size, But they meant in regards to flow, not just valve diameter. Many builders get hung up on big intake valves when in fact the exhaust flow is equally important in creating a long, strong, power band. Those thumper cams have earned a bad reputation for being all noise and no go. In theory they should do well in stock headed BBC because of the weak exhaust flowing heads.

[@javilsx363]

@@TonaldDrump686 i was asking because of the stock cam specs of an ls7 they are 210/230 and was wondering if you let the exhaust valve open longer would it hurt the power or gain any

[@324wes]

That's why we have big stalls lol

[@smilsmff]

if you are drag racing car then loss of 16 ft of torque will help not spinning tires

[@MrBlackbutang]

Still like a wide lobe sep .

[@esketitethan9679]

What is with the text being blasted over the screen

[@lobsterwhisperer7932]

dude looks like a heavens gate member.

[@unclesquirrel6951]

Personally I blame squirrels

[@markjmaxwell9819]

Australians are the LS engine experts. A race engine is different to a street engine. I like to build my engines so a stall converter is not necessary, or if one is a very small one. Americans have a bad habit of over caming engines. Most marine camshafts work extremely well for street applications. Lollll get a haircut. 😂😂😂😂

[@Compcams1976]

You're definitely correct about a lot of people getting "too much" cam for their engine setups! It's something our technicians have to battle every day. Turns out, you really don't need a "stage 3" camshaft for your otherwise stock 5.3 or daily driven Camaro. There's a lot more to camshafts than that peak power number!

[@3800TURBO]

@@Compcams1976 say I have a 3800 L67 twin turbo, twin Gtx35r and am shifting at 7400rpm. Car weighs 3000lb and is trapping 160mph at a moderate 28lb boost. Compression is 8.8:1, 231ci. Cam is a 236/230@.050 lift is .588/.580 with a 115 LSA. Would you say thats too big or too small. I was actually thinking to step up to something 245+ duration solid? For more top. What you think?

[@waynecotner3331]

Those 26319 springs are garbage

[@unclesquirrel6951]

Personally l blame squirrels

[@unclesquirrel6951]

Personally I blame squirrels