little 'ol 273
The advantage of the 302s is the hardened seats.
advantage after 20+ years? not likely. more advantagous is the Heart shaped chamber, closed chamber, and they have a thicker
deck to allow one to mill the bejesus outta them. theres also the vastly superior exhaust port, and raised roof on the intake
runners.
to the OP,
basically to meet your goals you need 9.5:1 or greater compression, a very good dual plain intake like the LD340 or EdelBrock
Performer RPM ( i wouldn't bother port matching them), BIG CAM.. solid, around 520 lift and at least 286 adv.duration.
holley 750 VAC.SEC. Carb, and 1 5/8ths headers.
with the heads cleanup the runners, put new 1.88/1.
50 valves, then port the pocket up to the top cut on the seat. chamfer the
bore on the intake side. this should get you pretty damn close to 300 ]crankshaft horsepower. anything you do above and
beyond this is gravy.
273 are awesome little engines, but you gotta remember it will take alot of RPM to make decent horsepower. or disregaurd everything
and you can just give it a 150hp shot of NOS.. lol!
if yah really wanna freak some minds.. sleeve it, stroke it, and it will still have all the 273 coding on it.
cheers.