JoeliusZ28

Ive been set on the cc503 for forever, but lately everytime i watch a video of one i just cant help but think it sounds too small. And when i say sound... i dont mean im looking for sound here, im using that to judge how it might behave in comparison to other cars ive driven.

My car is a weekend car... probably sees about 2k per year, and has 90k on it. cam effects dont bother me within reason. Lope, surge, etc make it all the more fun for me... but i dont want bucking to the point i feel like the car is taking abuse from it.

So im curious how the 847 is on stock heads. Will the limit of stock heads keep the engine from wanting to rev straight to 7k? I want to shift about 6200 rpm and i dont care if im not getting the "full benefit" of the cam. also approximately what is the rpm range... does it still have good torque about 2500 rpm? Would running 1.5 rockers help tame it down at all or would that just be a pointless power loss? Ive also read in my searching that some people have "degreed" their GM847s... what does that mean and what can it do?

Im planning on custom tuning the car myself, so that is not an issue.

marshall93z

Still waiting to fire mine up.

And I'll be the first to admit that I bought it for the sound! But I do have the supporting mods to make it not such a turd.

zhevy-1

I've had the 846 on my Z28 and I liked it. It was a good performing cam. Unfortunately, I've had a bad ported set of heads, and never got the chance to really tap into its might

After going thru a couple of stroker engines, and a lot of other stuff, I'm now in the process of putting in a stock bottom-end and a set of aftermarket heads, possibly a set of Trick Flow heads and the 847 cam and call it good...

JoeliusZ28

no one has this setup?

11secgen

yes the 847 cam works pretty well with stock heads.there is a thread about that here some place. 1.5 rockers are deff the way to go,you dont need the extra lift w/ stock ports.degreeing the cam is a way to check the valve timing and compinsate for anything that could throw it off,like chain streach or line boring the mains.most people agree that unless its a dedicated race motor,it isnt worth the extra cost.were talking two hours shop time for 10 hp at best, but prob little to no gain at all. with 90k on the engine your on the right track keeping the shift point at 6200,but in my opinion if your dead set on shifting at 6200 then the 503 might be a lil faster.i say go with the 847 and shift it at 66 when your racing,baby it the rest of the time.

JoeliusZ28

thanks i will try to find that thread.

Ive read that the 847 makes much more power from 4k up... but i dont know if that requires headwork or not. I want a monster on top but i dont want it to be dead under 3k either, i want some torque.

Kevin Blown 95 TA

Maybe you could set it up with some Rhodes lifters or some others that bleed down at lower rpms so that you have less duration and lift when you dont want it for just driving around. That's one way to lessen the effects of too big of a cam when you want to drive it normally.

11secgen

ive never seen a fast bleed roller b4,but there are alot of things ive never seen.

JoeliusZ28

ive never even heard of anything like that, would you have more info? Sounds quite expensive though.

Kevin Blown 95 TA

Heres a link to the site - http://www.rhoadsproducts.com/Pages/...lOERoller.html

They do make a hyd roller that will vary the duration. They're not cheap and they may be noisy which might cause a prob with the knock sensor.

Here's a discussion on them http://www.camaros.net/forums/showthread.php?t=35628

Check some other manufacturers for similar products.

dangalla

i would like to read that please post it, that cam really likes to rev out and i cant imagine stock heads are going to let that happen. if you plan to use stock heads you should really choose a cam that will utalize your usable rpm range

you should never install a cam without degreeing it.

it has nothing to do with chain streach.

it has nothing to do with line boring.

and i doubt you will find many people to agree with you statement here, if anyone

brain

847 is the best cam for the most power on stock heads. It will make more power and tq past 3000 rpms, and doesn't loose much before 3k, unless you compare to a stock car with manifolds. Here's my before and after dyno. Before is with LTs and CAI. After is just the cam and 1.6 rockers added.

Zigroid

you had a "\" where you should have had a "/"

what rpm do you shift at?

I'm putting a cam in my car that is slightly larger than a GM847 with stock heads and a freshened stock bottom end. just wondering where I can expect to shift.

11secgen

i bet you a buck about 90% of the cammed lt-1's on this message bord wernt degreed in when installed.
now i do agree with one thing you said, 'you should never install a cam without degreeing it''.it [I]should[I] be done, but often isnt with little to no negative consequences.now did i degree in the cam when i built my 7 second monza engine?of corse, but did i degree in the 847 on my otherwise stock lt-1? no.
line boring shortens the distance between the cam and crank,causing slack in the chain and affecting the valve timing,so i always throw the wheel on it when the engine has been line bored,same deal when a timing chain is being reused,the slack effects the vave timing.
now to get back on topic, these dyno results were exactly what this thread needed!

JoeliusZ28

i want to shift at about 6200 unless im really trying to beat somebody, ill take it a little higher.... but i want my bottom end to stay in one piece.

since i have started this thread im now thinking about going with either an AI or lunati cam... or getting a 224/230 or 230/236 ground really tight. Im think the 224/230 on a 108+2 would be a pretty wild cam without wanting 7k rpm shifts.