I'm looking for the correct lenth push rods to use on my engine. I've got a 90 model L98 and I'm going with tf 23* heads, lt4 hotcam and crane 1.5 roller rockers. I really need some help because I want to tear into the engine next week.

 

i asked this same question when i put my trickflows on, and the answer i got was that it's impossible to predict what length your gonna need. You HAVE to measure with an adjustbale length pushrod. The heads come with a reference guide that says what length they *should* be, dependent on what rocker your using. It's your job to verify that...

hope this helps,
Eric

 

Zupman has it. Measuring them is the way to go. But the TFS install guide has some common parts combos and what length they *should* need. As a reference, I am using 7.300" ones on mine with Comp Pro Mag 1.6:1 rockers.

Also, why are you even entertaining the idea of using the 1.5 rockers with those heads and the LT4 HC?

 

Having actually worked on a similar combo I can tell you DON'T go blindly by TF's specs on their web site. My ideal length pushrods (measured) turned out to be about .200" shorter than their recommended ones! Yikes!

 

I'm using 1.5 rockers because my boss gave me a good set for free. Also the heads specs say that .520 is the max lift. I don't think .005 would hurt but I don't want to take the chance.