cam shaft help
 

how does everyone choose the advance on a new cam if it is not ground in already like 4 degree advance seams a number a lot of people use. Where do I find the happy medium. Or what determines the advance you should set cam at?

cam
 

You need to degree your new cam when you install it.The cam manufacture may have advance built in the grind,or the timing chain and or timing sprockets,and key way may be off a little.You are only guessing if you don't degree the cam when you install it.There are several ways to advance or retard the cam,they sell a cam sprocket that you can move to set it where you want,or buy a crank sprocket with several different keyway's to set it with.In general if you advance the cam you will increase the power at a lower rpm,and if you retard the cam it will move the power up the rpm range,BUT there are always trade off's in doing this.Go to comp cams web site,they have a ton of info there,and here is a link as to how to degree the cam.

http://www.compcams.com/Technical/In.../Files/145.pdf

I know how to degree the cam what determines if you want to advance it . for more low end how much does 2 degrees advance change it or 4 degrees

Usually the size of the engine, compression, and weight of the car comes into play. If it's a heavy car and small engine most cam manufacturers recommend advancing it. EX: my car is 3200 lbs with a 377" it has a cam ground on 106 lobe ctr's. I install it at 102 for the torque needed. In fact i install almost every sm/blk racing cam at 102 unless it's a street engine with low compression. I have pretty good connections with Bullit and Comp cam, so i usually call and tell them what i have what do they recommend, with the enginge size,car weight,converter, gear and tire size.

JMO

Zip.

I agree with both replies. I had a 427BBC blowing the tires off at low end and retarded the cam. I picked up ET, because it bit and them screamed thru the top end.