2001 Z06 pushrod length question
2001 Z06 pushrod length question Here's the deal. I have a 2001 Z06, the motor was 100% stock until this past winter when I did a cam swap to a T-Rex V2. When I did this cam swap, I ordered stock length pushrods and when I was assembling the motor I noticed that when I pressurized cylinder 1 at TDC using air through the spark plug hole, with both rockers installed I could hear air passing by the valves through into the exhaust and intake, meaning that the valves were still open, meaning my pushrods were too long. I determined that they were approximately .050" too long, ordered another set, installed them, and went on my way. About 100 miles later, I had a bearing fail in one of my stock rockers, so I replaced them with a set of Harland Sharpes, fired up the motor and noticed louder than normal valvetrain noise(much quieter than the damaged rocker), but checked all components and found no issues. The car made 447/452 to the tires on a Mustang dyno so I am confident there are no actual issues with the valvetrain other than noise. I have since put about 2500 miles on the motor, and the noise has not got any worse or any better. As a side note, the noise was always there before the cam swap, just not as bad likely due to the less aggressive cam profile. For peace of mind, I just ordered a set of the Cadillac Racing lifters from GMPP, and am wondering will my pushrod length need to be adjusted to the new lifters or are they the same overall dimension as the stock LS6 lifters? Thanks for the help, Nick
TECH Regular
Joined: Jul 2011
Posts: 452
Likes: 2
When in doubt, get an adjustable pushrod tool to determine exactly what length pushrod you need for any setup different than stock.
You also need to know what your total lifter plunger travel is to know what length pushrod will give you the desired lifter preload setting.
Determining a perfect pushrod length takes some detailed effort.
You also need to know what your total lifter plunger travel is to know what length pushrod will give you the desired lifter preload setting.
Determining a perfect pushrod length takes some detailed effort.
Last edited by ZeeOSix; Jul 11, 2011 at 05:02 PM.
