i emailed comp cams this email:

i have a 350 in my 89 camaro. headers, 3" single exhaust, 2400 stall, holley stealthram. 3.42 gears. stock heads. max lift i think is right around .500
idle is not an issue. this is for street/strip. thanks


and he replied. "You could look at our part number 08-503-8. This cam has 276/281 advertised duration with 224/230 at .050. The lift is 503/510 and it has a 112 lobe separation"


does this sound right to you guys?

 

ttt

 

Here's my opinion, take it or leave it.

That's the famous 503 cam. It's a very good cam, however, it's not going to work with your heads unless you've ported it and had it clearanced for the lift. If using 1.6rr, your heads need to clear .544 lift at the valve.

In short, it's way too much cam for stock heads, and probably too much cam for your headers too (Edelbrock). Look for something with less duration, port your heads, or get better heads. I would just get better heads, you'll have to port the stock heads like mad to get the flow for that cam. I wouldn't use a cam with more than .450 lift on totally 100% stock heads. Any XE cam will be too much for stock heads. The lift is too high. If you really want to stick with stock heads, the zz4 is about as big as you can get if you're lucky (lift clearance). You can also look at the Crane PowerMax/CompuCam 2032. That will fit stock heads.

The stock heads really suck in stock form. You can't do a whole lot with it, you really need to pull it and port or at least clearance for more lift to get the zz4 cam in there. If you do clearance it and decide to put the 503 cam in without porting, your car is going to dog. The 503 cam likes to run in the higher rpm ranges...4k-6k. You might want more stall too, 3000+ and probably more gear.

Your also not going to pass smog with that cam in a 350.

 

i dont have to smog anyways so thats not an issue at all.

 

I agree that its way too much cam for stock heads.

 

I would look for a smaller cam. The problem is you have a slight mismatch of parts. That being the Holley Stealth Ram and the stock heads. So you need a cam that is in the middle. I would say a ZZ4 on the low end and a LT4 on the top. A ZZ9 would be right in the middle. Again your heads would have to handle the lift. That cam they recommended would be okay if you had AFR or say Trickflow heads. Allen

 

lets say i went with this cam anyways.. with a chip for it. would i still see any gains or would my power overall drop from the stock cam? if its none to slightly any better performance, ill go with that with new heads in my near future goal.

 

The problem with that cam and stock heads is that the stock heads will not handle the lift of that cam. You would have to remove your heads and have them reworked to handle the lift and increased rpm. Might as well buy new heads at that point. But yes you would see an increase. Allen

 

I have a CompCams CC304 cam with 210/220 and .500/.510" lift. That's going to go in my car with the LT1 heads and intake.

I'd look into something similar to that actually. Actually this CC304 cam probably has too much of a split-pattern cam to be ideal in my car except for when I'm spraying. My heads have an E:I flow ratio of around 85% whereas the stock heads are somewhere around 50-55%. You would take benefit of a cam with a larger split pattern. I *should* have the 212/218 XE grind cam, but its been a bit out of my pricerange, though I may be looking into buying one in the next few weeks. Want a 210/220 cam at a good price?

 

Yes, couldn't agree more. I think we keep telling you the same thing in multiple posts from different people, not just myself. Assuming you get the retainer to valve seal clearance, there's still the issue of the pressed-in studs which will become unpressed at .510" lift. You need screw-in studs. Basically you need to pull the heads.