LT valve clearance
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TECH Enthusiast
Joined: Jun 2006
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From: Enid, OK
LT valve clearance At what valve lift do you have to worry about poiston to valve cleareance on an LT? Buddy wants to run a cc503 or a similar cam just more lift at .575/.575. He will be using 1.6 roller rockers as well.
the lift is not the problem with P/V clearance. By the time the cam reaches .500 lift or max lift, the piston is way down in the bore. The spot that P/V clearance gets close is when the intake valve starts opening and the piston is still at TDC and just starting to go down. This is where the valve chases the piston for a few crank degrees until the piston speed picks up and where P/V is the closest.
The duration and lobe center line are the things that really effect P/V clearance on any engine.
That being said, the LT1 is blessed with tons of P/V clearance and you can run that cam with no problem at all and lots of people run much larger cams with no problem on a stock bottom end.
*disclaimer- it is ALWAYS suggested to check P/V as well as degree the cam even though these steps are very often skipped.
Lloyd
The duration and lobe center line are the things that really effect P/V clearance on any engine.
That being said, the LT1 is blessed with tons of P/V clearance and you can run that cam with no problem at all and lots of people run much larger cams with no problem on a stock bottom end.
*disclaimer- it is ALWAYS suggested to check P/V as well as degree the cam even though these steps are very often skipped.
Lloyd
