82CamaroZ28

I'm planning on building a 350 towards the end of the summer, and don't want to spend a whole lot of money making the 305 faster, but I was thinking of getting a new cam for the time being. I am looking at the COMP XE256H. Only thing that I am wondering about was if I NEED to change the valve springs. The motor has around 70,000 miles on it. Also, If I do, how hard/time consuming is it to change them while the motor is till in the car without having to worry about losing a valve?

Here are the cam specs:

COMP XE256H
RPM - 1000 to 5200
LIFT (1.5 Rocker) IN/EX - .447/.454
LSA - 110

Extra info:
Motor is an LG4, Automatic Tranny, 3.73's

Any other cam suggestions are also welcome.

Thanks,

Matt K.

RB83L69

Yes, you need to change them. They are garbage. They were garbage the day they were installed.

You also need to throw the exhaust rotators and all that garbage into the garbage where it belongs. Get the right retainers and keepers that go with that cam. Use .090" of valve shim (one .060" and one .030") under the exhaust springs.

It is very easy. One at a time, bring the pistons to TDC; push a piece of 3/8" nylon rope into the cylinder until you can't cram any more in; and change the springs on that cyl. Should take no more than 4 or 5 minutes per cyl.

All ofthis can be transferred to a 350, if whatever heads you end up with come without springs.

82CamaroZ28

Could anyone tell me what diameter shims I would need for the stock LG4 heads with the new COMP valve springs?

ede

for stock springs you need 1.25 dia. shims

82CamaroZ28

Thank you.