Not the best example but my buddy has run a 650DP on his 55 Chevy for years, it's a 427, turbo 400, 4:56 gears, 9x28 DOT slicks, he drives the car quite a bit & around town the small carb really helps drivability, at the track with the 650 he's run consistent 12.0's... With a 850 & lots of tuning he's run a 11.92... Personally I think a 650 would be fine for a healthy 383....

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