Spring installed heights? Something doesn't seem right? IMPORTANT!
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From: Waterloo, Ontario
Spring installed heights? Something doesn't seem right? IMPORTANT! I just finished checking the installed height for the valves on a 01 Z06 head. With the stock Z06 spring(01) and valve the instaled height is 1.89. Now using a PRC Ti retainer and seat the installed height with the same valve is 1.73 inches? I believe they advertise the height to be 1.8? At 1.8 the springs are good for .660 valve lift at 1.73 we just lost .07 valve lift which means the springs are only good for .590 lift. Can someone else verify this? I'm going to check again but it seems to me the reatainers are not machined properly to achieve the correct height.
Thread Starter
8 Second Club
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Joined: Oct 2002
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From: Waterloo, Ontario
I just checked again and got 1.765 as a installed height for the PRC's and the 01 Z06 valves. I'm using the factory locks. The pushrod length for the 01 and 02 Z06 is the same-I checked it too-I have both. I think they increased the valve length of the 02 valve( hollow). I .765 still only leaves valve lift to .625 versus the .660 at 1.8. This could cause problems for guys using cams like the G5X3 and the Texas Speed MS3 as they have exhaust lift approaching .610.
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Joined: May 2003
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From: RainbowCity,Alabama
The kit is designed to install at 1.800.I will check one today and see what it comes to.I will check this one a stock LS1 valve.The spring will not coilbind until 1.07.If the installed height is 1.765 - 1.07 = .695.This will not be a problem with the large cams.
