Trying to figure out what size -cc piston to get for around 11:1-11:5 to 1 as long as its under 12:1 with a 039 felpro gasket and 53cc heads It will use 5.85 rods.

 

You need to specify the piston deck to calculate CR. Makes a big diifference. Theres a CR calculator right here on cz28, as well as many other places on the Web.

396 with +0.005 deck and -18cc dish = ~11.32:1
396 with 0.000 deck and -18cc dish = ~11.18:1
396 with -0.025 deck an -18cc dish = ~10.56:1

Rich Krause

 

Here is one of the links Rich was refering to-
https://www.camaroz28.com/calcs/cr.html

You need to know what your other variables are, in order to play with the one you are still trying to figure out.

Moving to LT1 Tech also.
Thanks.