i'm in the process of building my lm7 and was wondering what pushrod length i should order with the new cam im getting.

Cam specs:224R , .600"/.600" 112 LSA

Includes TSP .660" Dual Spring Kit w/ PAC Racing Springs, Titanium Retainers, Hardened Spring Seats, and New Valve Stem Seals

with 243 heads

ls7 lifters

ls9 head gaskets

anyway this is the first build ive tried to do let me know what ya'll think should be my pushrod length.

 

I think you should measure, but 7.400-7.425" should work if you're not going to.

 

Like KCS said-you really need to measure it to get it right. I just went through this and wound up ordering push rods that are 7.300 (actually measured 7.315") for my engine. I have milled heads, Howards Cam, and Fel Pro head gaskets. But, what engine parts you are running is irrelevant as measuring is the only true way to know what length you need. If I had tried to run the factory length push rods, it *might* have worked, but it would have been running a TON of pre-load.

I have an adjustable push rod I can mail you if you want to borrow it. Once you figure out where ZERO lash/ZERO pre-load is on the base circle of the cam shaft, you then just measure it, and add whatever pre-load your lifters call for, or whatever you desire to run, and then order the correct length push rods from there.

Comp Cams also makes an adjustable push rod that you can purchase and use that comes with graduations that you can calculate length with. Either way, just measure it and have the piece of mind that everything is correct. I could not, and would not, just choose a stock length, or any random length, and attempt to run it. These engines seem to be very forgiving though and you might just be fine with whatever length you throw at it. Your decision.