look at my sig, I'm doing just fine with my 670 for the 300hp range and maybe more. If you are running a 383 like your name implies then I would go with the 4 bbl. Either way you will need a custom chip among other changes to the sensors.
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1988 TA 300+hp 350 w/ TBI and Holley TB unit, Holley projection intake,
WC T-5, 3.42 gears w/ Auburn posi. MSD 6A, edelbrock TES headers, dynomax 3" cat and cat-back system, ACCEL coil, polyurethane bushings all around, aluminum driveshaft, Mr. Gasket open air cleaner.
1993 S-10 w/ 4.3L V6 TBI, slightly bigger cam, Mild polish job and 3 angle valve job on heads, Edlebrock TES headers, Dynomax cat back, MSD 6A, ADS chip
2000 Kawasaki KX 125 | 
