compression math question
 

OK I have a 3.2 bored to 3.4 with stock crank anyhow I used to have a stock crank. The stroke on a stock 3.2 is 74.4mm the stroke on a 3.0 crank is 70.4mm I have 3.2 rods and JE 10.5:1 pistons. If I were to use the 3.0 crank instead of the 3.2 crank what would the compression ratio likely be. I know it would be a significant drop. Perhaps that would put me back into turbo or supercharger range

Your best option is to use the 3.2 crank and order some custom pistons once you have measured everything else so you can get the exact set up you need.

What is the difference in length of the rods? I think that If you use your current pistons and 3.2 rods on the 3.0 crank, you are going to loose deck. You are also going to loose displacement. No matter how much fuel and air you force through it, it will run like sheite and assplode.

Also with that deck height you will have a compression ration of about 3.5:1.

RSR Static Compression Ratio Calculator