[408cobra]

I checked the je web site and they have one piston that will work with your combo. I assume it is a 4.030 bore with 4 inch stroke and a 6.2 inch rod. It is listed as a 9.6 comp ratio with 58 cc heads and has a negative dome of 30 cc's with this piston your comp ratio would be 9.503 using a zero deck height and a .040 thick gasket with a bore odf 4.030. This would work fine in your setup here is the part number 170393. Keep us posted on your findings. Good luck this is a weird one