[hugger6933]

Welcome to the site, you didn't mention what the 454 was out of if it is a truck say 79 or newer up to the mid to late 80's it has peanut port heads and they are a log jamb for air flow[read POWER and TORQUE]. If that is indeed the case being a later 454 also the compression is WAY low like a 7:8to 1 something crazy low like that. Now if the 454 say pass hi perf on the block and heads you in better shape it is still most likely a oval port motor but you really need to make stupid crazy power to need the rectangular ports. Jim