Some of you may be aware that I recently burned up my 1.5L "Franken" engine during competition at The Ohio Mile. One cylinder went to zero compression after the top of the piston partially melted and got into the cylinder wall. Another cylinder was close behind.
EGT's were 1600F or so at the time, running 40+ psi boost along with a lot of fuel, and water injection.
In any event, for the "next" incarnation of this engine, I'm considering having a slight taper machined into the area of the pistons above the top ring groove, to allow for additional expansion in this area. I understand that this is somewhat common in sled pulling tractors and the like.
Has anyone here employed this technique, and if so, any words of wisdom?
Steve.