hey fellas,
I've began a build of a 68 mercury 390 to put in my 76 F350. Its a daily driver and i want great compression for best mileage and street power i do like to have more 'go fast' for this truck.

Right now the block is .030 over with what look like sealed power dished pistons if i remember right they are a 304np? seem like a std type piston and would yeild fairly low compression.

what would these pistons set me up with now as far as a compression ratio and should i go for some '360' pistons since they are of a bigger compression height and technically a flat-top? OR should i go as far as getting a dome topped piston to yeild more.

Im wanting at least a 9.5 to 1 or 10to1 compression unless ya'll have a better recommendation?!?

thanks everyone