Originally Posted by Wmarden
Which cam should I go with for my pontiac? Ok let me give a few details. It is a pontiac 400 and will be rebuilt, but I need to start figuring out which parts to buy. SO I was looking at a few pages and decided to pick a cam.
The motor will be mostly stock with some overbore as needed. Heads will not have much work, they are 62 heads which have 72-75 cc combustion chambers. With those small chambers I feel I need a cam on the smaller side for street use to keep the detonation away as much as is possible. Plus to be honest, I am not much of a racer, I just want a decent streetable cam. The car it is going into is a 71 cutlass. So it is not going into a lightweight vehicle.
Edelbrock has one that looks good(the basic performer cam), but I could not get onto the comp cams website to do some comparison shopping. Plus I am also looking at budget here. I don't want to cut corners, but if I can save a few bucks for a comparable product, then of course I would go that way. I know enough to know I don't want a used cam because I wouldn't know what to look for or how to tell it was good. And besides the cam is perhaps the most important part of your motor.
This is an old thread, but he cam to use is a Comp 268 in a stock Pontiac like this, and is you get the pistons with 8 valve reliefs per piston, with the edge of the entire top of piston chamfered, that basically adds 16 cc's and lowers the CR a lot. Those pistons with a 400 .030" over will yield 9.6 CR which is a tad high. With 75 cc heads it may "just" make it. Or machine the piston a little to add 5 more CC then you're ok. I prefer to have 9.25 CR or lower with iron heads. After building many Pontiacs over 30 years time, they ping with any compression over 9.5 and iron heads, on pump gas.