I've been searching here and google trying to find what would be a suitable cam for my motor.
I've got a 97 l31 vortec motor running the edelbrock performer rpm intake, a holley 670 street avenger carb and hedmann LT headers to a dual exhaust, the whole short block is bone stock.
I'm looking to find a mild cam to fit my application, there is a difference in a cam for a FI motor and a carb motor right? I can't just use a stock lt4 cam can I?

thanks for any input you guys can give me.

also FYI I would prefer to keep this a low cost build, so if I can avoid modifying the heads to get more lift on the cam I will.

 

Call Jegs or summit and run it by them, but be aware that with those heads, unless you machine em, you cant take more than .420 lift. (Trust me, Im in the middle of a debacle over this one.....my engine is in pieces and Im still trying to do this vortec swap.....)

If you DONT want to machine them, it wont be much worth it. I just bought a .470 cam from Jegs, the whole package (cam, springs, lifters, timing gears, retainers) cost me less than 300, but I HAD to het the valve guides taken down and that was 100 bucks in machining.....

 

Cam lift is more than just a piston to valve clearance issue.

When using slotted stamped steel rockers, if there's too much lift, the rocker will hit the rocker stud. Roller rockers don't have this problem.

Also as mentioned above, if the lift is too great, the bottom of the spring retainer can hit the top of the valve guide/seal and the guide needs to be machined down.

Stock springs can only handle so much lift. At full lift, there should be a minimum of .060" between the coils.

There's also valve train geometry. You need to keep the tip of the rocker near the center of the valve stem through the entire lift range. This is done with different length pushrods. For what you're doing, stock length pushrods will be fine.

 

Hmm I was thinking that the machine work would cost more than that. I'll have to go to my local speed shop and talk to the guys to see what they'll charge for the work. Do you have a part number for the kit you bought? And what's the rest of your setup?

 

I agree with above, you could also go onto comp cams website and/or call them. Comp's website has a pretty neat desktop dyno you can download that can give you an idea of different cam horsepower and torque curves and what nots.....it is pretty neat and also pretty accurate...mine was only 15hp off of actual dyno run.

 

I tried this but I use a mac computer and their download is for pc users. Anyone nice enough to plug in my info and let me know what's up?

 

actually if you are not in that great of a hurry. like i am not. you can email them with all the specs of your engine and what you want to do with it. they will send the best cam specs and what all needs to be done to run it.

 

Sounds like a solid plan

 

You can also call comp cams. I found them to be very helpful. By the way, it cost me only $280 to have my heads completely rebuilt, resurfaced and machined to handle the lift of my cam, which is .48" int. and .488 exh.