Hi Folks,

I am doing a Mazdaspeed Miata build for Street Prepared autocross. One of the allowances is up to a .0472 cylinder overbore. The replacement piston rule is the difficult part. I can use a replacement forged piston but it must be pretty much a copy of the factory piston. It must be the same weight or heavier, same quench area design, and same ring configuration.

I tried to find the Mazda oversized pistons even though they are only .020 over. They are no longer available from Mazda.

Has anybody gone down this path? Is there an aftermarket piston that matches the Mazda design? Anybody have a set of the .020 over Mazda pistons for sale? I know I could go custom but I am running out of time.

Thanks in Advance.

 

All the aftermarket pistons I know of use a different ring config (narrower rings). You can have a custom piston made to meet those specs, though.