hey dude....i just exploded a 496(455 olds bored and stroked)on the dyno stand and im out a lot of money...not saying the 455 aint a good motor its just more common to build up,im building up my olds 350 and im gonna get some serious power out of it and im talking about the same motor you got...i have a 68 "s" and i have the original motor and its a 30 over motor that is currently undergoing a re ring of the dished race pistons(already in the motor when i got the car) and a re bearing of the block...the heads are # 5 castings and will undergo some heavy work to match the 4500 flanged offenhauser port-o-sonic intake i just picked up and i will be running lunati cam and lifters and harland sharp rockers. im hoping this combo will yeild me the numbers im looking for. just build the 350 and then when you find a 455 then swap it out. best of luck and happy mustang hunting
