I noticed in their advertising when I ordered my pistons years ago, it was Auto Tec/Race tec, I wasnt sure which one made them, LOL.
Wiseco makes a pretty good piston. Also custom though but I bought my last 2 sets for about $1100 a set. Jim
The stock (1964 Buick 300) low compression piston has a recess with a depth of about 0.156", at least when I measure my used pistons. Measured directly, I got 16.5 cc, which agrees, more or less, with the 15 cc that's quoted for these pistons. I found a set of stock high compression pistons (they were hiding in plain sight). The recess is 0.020" deep. This translates to a volume of about 0.8 cc. The stock head combustion chamber is supposedly 57 cc. I measured several of mine between 51 and 52 cc. My heads have not been cut. However, even if my heads had been cut 0.015", this would only reduce the head volume by 2 cc. I have no idea where the published recess size of 0.230"-0.245" comes from. Export piston perhaps? Also, with my low compression engine, the piston sits 0.034" in the hole, which is in agreement with the specs allowed by the NHRA. However, in my high compression engine, the piston sits 0.045" in the hole. I'm going to chalk this difference up to factory tolerances.
Differences in the compression height of the pistons. For instance my Wiseco pistons have a 30 or 35cc dish but sit at zero deck and run with a TA head to give a 10.5cr and a .040" squish with composite head gaskets. Jim