Keith black 383 pistons

I am building an engine now with .060 over KB 400 pistons. I had problem with the first one though.
My first 383 was .030 over with KB400s stock rods were honed to float on the pins. the engine was a roller cam motor with stage 4 heads around 12 to 1 compression. Ran 11.00 flat in the quarter in a minitubbed 67 barracuda for about 40 runs the engine broke after shifting into 2nd at 6500rpm. inspection revealled that cylinders 7 and 8 broke after the wrist pins locked up. The pins were gun metal blue and seized in what was left of the pistons.

Since then I have used KB240 pistons (same thing but for the 400 and flat top) with Eagle full floating rods, and have at least 60 passes shifting at right around 7000rpm. this engine has no block filler. But the next one will have.