Optional 9.4:1 83mm pistons
Posted: Fri Jul 26, 2013 9:13 pm
In case anyone might be interested - if you plan to bore out a 7 rib block 2mm (total of 83mm) you can use 1991 Miata pistons. They are 83mm with 20mm wrist pins.
How much performance do you really get out of boring over that much on the 4a? IDK if 7a & 4a wrist pins are the same but I was reading the honda a20 pins match with the 7a, so they could be swapped in. That pushes it to 82.75mm.
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