I have a set of 81.5mm Wiseco 11.5:1 pistons and a set of 81mm SRP pistons not sure of the compression. Does anyone have a guesstimate on the compression of the SRP. There is no part # on the piston anywhere.

both pistons Wiseco on the left SRP on the right



Wiseco



SRP

 

Impossible to guess. You'd have to measure the piston in detail and/or install it and then cc it in the cylinder to calculate it.

 

wiseco number on top suggest they are 11.8 to 12.25 compression so from the looks of it the srps are probably 12.5 to 1...look on their website and check what is the highest dome they make...

 

The highest compression piston I see on their site is 12.0:1. I am going to ship one of them back to SRP so they can tell me what they are.