The best heads up rectangle vs. oval port test I have ever read about is on a sight called Maliburacing.com Its awesome, and you wont doubt for a second that oval ports are the correct choice for most anything 500cid and under that doesnt see rpm's over 6K regularly.
This is an interesting comparason between the oval and rectangular heads. This is a really mild combo, but I think you would need to get a lot more radical (as far as cam lift) before the rectangular heads would really start to shine.
I built my 468 with Edelbrock RPM performer (oval ports) for a street strip application.would i have been better off with rectangle port heads
Not on the street it has been proven more than once that sq port show very little improvements over OP Especially on a 454 which is a grunt motor and works on torque vs hi winding. Gear it right and you dont need all the rpm as well the breakage factor which can come with hi rpm motors
I guess it all depends on what you want to do with your ride. I have tried several different heads (including 781) and the 074 rectangle ports worked the best for me. I'm not out to be the fastest.... but I am trying to be the most consistent.
I see the old rectanuglar vs. oval port debate is still alive and well!
I state this AGAIN for those that haven't read it here or elsewhere...
it is a FACT that my 11:1 467 oval port engine combo out performs EVERY n/a 454-502 combo regardless of bore/stroke/compression/heads/cam yada, yada, yada in a similar weight Chevelle(3880 lbs.) in Division 1 brackets as well it's makes more power/runs quicker than most 540's and GM's 12:1 720HP 572 again in a Chevelle of similar weight to which most comparables are hundreds of pounds lighther.
Further this car/combo is DEADLY consistent, typically varying thousanths in 60 foot from run to run and 2-3 hundreths over the course of a full day/night of racing!
OH and it sees over 6000 "regularly" as in EVERY pass, making the 1-2 shift at 6600 and 2-3 at 6800!!
FYI, my new 522 engine that will see north of 7000 RPM regularly will also have oval port heads!
So to answer your question....
Last edited by FOOTBRAKER; Jun 25th, 07 at 8:59 PM.