when you say "MODS"...do you mean bolt on stuff etc..i noticed you mentioned taking off the heads etc....if you start doing this then the game plan changes......Yes heads will make a Big Difference for the street..
i recommend the Oval part smaller head for your application if you want to go that route....other wise i would just do the basic Mods as we did back in the late 70's early 80's on our rides in H.S.
1- Good carb..( NOT TOO BIG)...if anything smaller for that motor. 650 holley double pumper is a good choice.Good wires and many extra plugs to keep to keep them fresh..street motors will gas foul every now and then when stop and go in traffic.
2- Good hi-performance HEI ingition..or the 8551 billet MSD dristbuter with 6al box..i personally think the HEI will be good enough.
3- Good set of Hooker 'TUNED" HEADERS with flow master exhaust tied in toward the back side of exhaust...3 inch exhaust pipes minimum.
4- a hydraulic roller camshaft with roller rockers..IF you change heads get the cam package to match....if you do not change cam then roller rockers by themselves will still be a HUGE HELP..in freeing up friction
5- Good aluminum intake desined for the street. if you change heads and cam the will recommend a certain style intake..but the intake alone will help over a cast iron.
we got our stock Motors to run pretty good by goiong what i mentioned above back in the late 70's early 80's...we could squeeze all a small block could give back then with stocks parts...you could also find a pair of double hump 300 horse heads anywhere back then..i can remember paying $20.00 a set for them.
leaving the bottom end alone and replacing the top end with what i mentioned can really wake up your stock BIG block.....i would say $2500 and you could have a pretty nice street Big Block.
thanks
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Bjuice..
"I'M YOUR HUCKLEBERRY ! "