tim.huntoon

Hi, I have a 1978 corvette with an L82 and a set of blueprint 195cc heads. I was wanting to get some more power by added a bigger cam and I was wondering how big of a cam fits in an L82 with a stock bottom end and still have good clearance. Also what are some good cam recommendations for an L82.

Milan454

Hi Tim. First off you can add a mild cam up to a .500ish lift. But ultimately you will need to have your valve retainer to valve guide clearance be adequate in addition to the piston to valve clearance. There is a good amount of engine math to consider as well as compression ratio that impact cam selection. Have you tried Comp Cams cam selection software? Its always a good starting point.

rklessdriver

Max lift has no effect on piston to valve clearence.... at max lift the piston is near the bottom of the cyl.

What matters is valve timing. Specifically how early BTDC the Intake opens and how late ATDC the exhaust closes. These 2 events are the only times the valves and piston are near each other.
Will

gkull

You might even add in the diameter of the valve and the notch size in the pistons. It is okay to machine forged pistons for minor valve clearance problems. I would tend to say that you should measure everything when assembling. I did throw some good heads on a stock l-82 short block. The cam was 238/248 with mid .500 lift with 1.6 rockers It was something like .548/.566 and it has something over .055 valve clearance.

cv67

What Will said
.640 lift after lash (little easier to do with a roller)with decked block & heavily milled heads clearance is fine; its all about timing.
x2 on setting up the springs right that is SO important. Keep us posted

edit-plenty of good FT cams to use out there