building an iron 346 with ls6 cam and 317's. im also running the ls9 gasket. the ls6 cam has a smaller base circle so i know ill need the 7.425 lenghth. im wondering if i need to go a little longer since im running a thicker gasket? Anybody running a similiar setup please chime in. Thanks!

 

measure it to be sure.. thats the best way!

 

forgive the ignorance but how do you measure?

 

With a push rod length checker

 

You need to assemble the engine minus the pushrods. Install a pushrod meausuring tool in place of a pushrod. Make sure you are measuring a cylinder that is at tdc and has both valves closed by the way. Tighten the rockers down to 22 foot pounds extend the push rod measuring tool until you have zero lash. Remove the pushrod measuring tool and measure it. Take that number and add it to the preload you want to run and you have the length of pushrod that you need to buy. Example:
You measure the pushrod measuring tool and it measures 7.34"
You want to run .060" of preload
7.340" + .060" = 7.400"
You would want to buy 7.4" pushrods.

 

I just watched a video on it. how do you know when you have zero lash, and when do you know when piston 1 is at tdc. Ive seen a guage but is there an easier way ie cheaper?