Our engines use non adjustable rocker arms, so pushrod length is import to lifter preload, which is important for performance. Incorrect preload does change power on the dyno, or in extreme cases, the ability to run well or at all.

There are 2 options for the adjustable pushrods, a shorter option custom made for wot-tech for use on 3100/3400/3500 LX9 engines. These measure below 5.700", which is very short for an automotive engine. The other option is a Comp pushrod that measures 5.800-6.800. This is good for all flat tappets, and the VVT engines (with or without bearing spacers).



Besides the adjustable pushrod, you will need a 12" caliper or other accurate measuring device that is accurate to .001", and a socker for the nut/stud holding the rocker down. For this example, we are using a Gen 2 2.8 V6 with flat tappet cam and pushrod guideplates. The nut holding the rocker is 13mm



I like to rotate the engine so both intake and exhaust lifter are on the base of the cam lobe on Cylinder 1. You can use any intake and exhaust to measure, or you can measure every single one Minimize the length of the pushrod and set it in place, then tighten the rocker arm down.



Extend the pushrod until it is long enough to stay in place with no side to side motion, or pushing down on the lifter hydraulic.


Good


Bad

Once you have the length you need, hold the pushrod so it cannot spin, and loosen the rocker arm.



And finally measure it.



Repeat for the intake (or exhaust if that is the one you started with).

For flat tappet cams, add .050"

For roller lifter cams, add .075"​