I have a 427 chevy engine date coded nov 68 block no3963512 headno3917215 these areclosed chamber oval port ,port matched JE pistons 9.6 to 1 a torker 11 intake with a GM nitrided forged steel crank , Lunati solid roller cam with roller rockers . due to a divorce this engine ended up with less than 500 miles on it . Not even broke in.Motor was pulled from a 69 Corvette $5000 firm