- Joined
- Dec 7, 2012
- Messages
- 3,597
Will need to determine the correct pushrod length for the LSx I am building. Also, I have always thought my LQ4 valve train was noisy. I just threw in stock length pushrods and truly do not know if my aftermarket cam has a different base circle than the OE LQ4 cam. Very well could. So I figured I'd measure and see what I should be running.
So I bought an adjustable pushrod and an 8" caliper.
Looking it up online, seems easy. Get intake or exhaust (depending upon which one you're measuring) on base circle, install adjustable pushrod and rocker arm, tighten/torque rocker arm and expand pushrod until you have zero lash. Remove rocker and adjustable pushrod and measure length with the caliper. Easy, makes sense.
Then you add whatever preload your lifter manufacturer specifies to that length and you order/install that length pushrod. Correct?
Is the measurement skewed if the engine is cold (sitting overnight) or if you check it an hour after running? Is there a best time to check this?
Also, what would be a safe or good preload for stock OE lifters in an LSx? Say LQ4, LM7... any junkyard or OE motor. Also, what about LS7 lifters?
So I bought an adjustable pushrod and an 8" caliper.
Looking it up online, seems easy. Get intake or exhaust (depending upon which one you're measuring) on base circle, install adjustable pushrod and rocker arm, tighten/torque rocker arm and expand pushrod until you have zero lash. Remove rocker and adjustable pushrod and measure length with the caliper. Easy, makes sense.
Then you add whatever preload your lifter manufacturer specifies to that length and you order/install that length pushrod. Correct?
Is the measurement skewed if the engine is cold (sitting overnight) or if you check it an hour after running? Is there a best time to check this?
Also, what would be a safe or good preload for stock OE lifters in an LSx? Say LQ4, LM7... any junkyard or OE motor. Also, what about LS7 lifters?