Valve springs question

BlackVert

15 Year Member
Oct 3, 2003
5,589
9
98
Bethesda, MD
Is the rating an indication of how much pressure the springs exert on the valves to keep the valves from floating at high rpms?

If my valve springs are rated for up to .500" lift, can I "get away" with a cam that lifts the valves to .512" and .533" if I keep the rpm below 5000?

I never rev my engine past 5000 rpm anyway.
 
  • Sponsors (?)


actually, it was ... which shows how little i know about that part of the engine.

but i am realizing that it is more than just a question of valve float. it also has to do with the thickness of the spring when the valve is fully compressed and if the lift is too far, then the springs hit bottom and things can and probably will break.
 
That part of the question i can see. But the part about never revving above 5k kills me. I mean comon?

Anyways, my one tip in the car game, just the spend the few extra bucks and do it right. Dont cheap out on springs, crappy heads, crappy pistons, and so on.
 
On a stock h/c/i car you shouldn't rev past 5k anyway, lose power. Better to shift at 5k.

but seriously, get the correct valve springs. Because everyone knows how easy it is to accidently rev the motor out by missing the brake pedal, or missing a shift.
Scott
 
BlackVert said:
If my valve springs are rated for up to .500" lift, can I "get away" with a cam that lifts the valves to .512" and .533".

The answer is NO. If a cam has a .512 lift and your springs have a bind height of .500, then you are going to bend pushrods and break things.