Max Valve Lift Question
Thread Starter
Racer
Joined: May 2001
Posts: 401
Likes: 0
From: Carlsbad CA
Max Valve Lift Question
I have pretty much decided on the Trick Flow 23 deg heads, but I need to make sure I understand max lift numbers.
I have a Comp Cams XE-268 in my car, which has max lift for intake of .477 and exhaust of .480 with 1.5 rockers. With 1.6 rockers, max lift is .509/.512. The heads are available with three different valve springs: max lift of .520, .540, and .600.
Now the question: aside from the fact that I may someday put a higher lift cam in the engine, do I need to worry about how close to max lift of the springs I get with my cam? Are these numbers absolute, or do I need to add in some sort of additional tolerance. 0.008 clearance from max lift of the cam to max lift of the springs seems a little close.
Thanks.
:flag
I have a Comp Cams XE-268 in my car, which has max lift for intake of .477 and exhaust of .480 with 1.5 rockers. With 1.6 rockers, max lift is .509/.512. The heads are available with three different valve springs: max lift of .520, .540, and .600.
Now the question: aside from the fact that I may someday put a higher lift cam in the engine, do I need to worry about how close to max lift of the springs I get with my cam? Are these numbers absolute, or do I need to add in some sort of additional tolerance. 0.008 clearance from max lift of the cam to max lift of the springs seems a little close.
Thanks.
:flag
Drifting
Joined: Dec 1999
Posts: 1,462
Likes: 1
From: Reno nevada
Re: Max Valve Lift Question (thebruce)
I would buy the .600 springs. The larger a spring is th cooler it will run. The larger spring is also added protection against valve float. I use .600 springs with my .530/.546 lift. You not even stressing them. Mine have be on for about ten years
