I understand you want a motor for street & track racing, with a relatively modest goal of 375 bhp. 15 mpg fuel economy. Powerband of 2000 to 6500. Want to use your 4V open chamber heads.
My first suggestion shall be a 3 3/4" stroker kit, taking you to 383 cu.in. This will help throttle response with the big-port heads.
Second, toss the stock rockers for a set of roller rockers & adjustable valve train. You'll pick up 15 bhp in the process.
If you want to keep the induction system under the engine screen go with the Blue Thunder intake & approx. 750 cfm Holley. If you want to poke the induction through the engine screen, try the Parker racing funnel web & port stuffers.
Call a cam grinder that knows clevelands, like MME or Reeds, to have a cam ground to your needs. They can take into account the compression ratio limitation of your open chamber heads.
You need an oil pan designed for track racing.
Look back at previous threads at this bulletin board, the DeTomaso mailing list & the Cleveland engine forum.
good luck, keep us informed as your build up progresses.
George
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