According to Mike at ABT, the stock head gasket was not a good match to the custom Wiseco 85mm pistons I purchased from Flyin’ Miata.  I had read that the stock head gasket could fit “with careful alignment” and possibly “some minor trimming”, but I trust Mike more than the innernet.

With an order going into Maruha anyway, and with the in-stock availability of their 86mm head gasket in multiple thicknesses, the decision was easy.  We only needed a stock thickness gasket, so I ordered the 0.8mm thick version.

This head gasket, along with the current deck height, should give us the exact piston-to-head clearance (squish or quench area) we are looking for.  Incase you haven’t heard, it’s all about the quench!