Okay so I got the 7.35 PR's set in and installed one. Went from zero lash, and to achieve 22ft lbs it took me 1 1/4 turns. Consensus says 1 turn is .047 preload so 1 1/4 nets me .058. Which I was shooting for .075 and fell a little short. Next I thought what the heck and tried it with the 7.4's and I am getting just above 1 3/4 turn or .082-.09 which is of course above .075. Really don't feel like buying 7.375's at this point so what PR should I go with?

I have checked multiple times and for zero lash on my PR Checker I get 7.275 adding the .075 preload I should need a 7.35 PR then right? Is the turns with the torque wrench the better math to go with or is it the PR Checker + Preload?

Might be over thinking this as usual, but I don't want to fall too short on either side! Am I measuring something wrong or does my math look legitimate?

 

Go with the length checker. I never trusted that turn method.

 

Thanks Atomic, I agree with you on that! Seems like it would be only a good "ballpark" figure using the torque method.

Well for the hell of it I thought might as well throw a Dial Indicator on and just see what I get.... I am not sure "at all" if it was done correctly, and have only heard word of it never seen someone do this in person. Granted its going backwards so you have to read the red numbers, but basically it is just shy of .08 preload once torqued down to 22ft lbs.

BTW this was tested on the 7.35's so the PR Checker is more on spot if I did it perfectly....?

 

On those numbers I still think 7.350" gauge length would be best!

 

dont trust the turn method IMO. measure to zero lash and add your preload from there.

 

Thank you for posting up the thread, it was good information IMO.

 

That dial indicator method seems like it would achieve the same results as a length checker, assuming the spring isn't compressing when you're torquing to 22 ft-lbs.

 

the dial indicator will only work if you have a few different sets of pushrods and just want the best fitting. the adjustable can tell you which pushrod to order.

your results with the dial indicator shows exactly why you shouldnt trust the degree of turns method.

 

Since it was my first install with aftermarket Pushrods and going with the taller LS7 lifters I most definitely used the PR checker. Glad to know that using the checker installed to zero lash and adding .075-.08 gives me a much better approximate PR length in the end after torquing to spec. Rather than using the torque/turn method.... $19 was money extremely well spent on the checker! Thanks everyone for their input!