Recommended 4bbl carb for stock 318

The 625 street demon may also be a good carb, I ran one on a stock 318 for a few years, it has small primary which help with throttle response and mileage.

I have had no issues with this carb, but you do have to buy the mopar throttle rod, because the stock one off the 2bbl will not work.

Demon Carburetion Street Demon Carburetors 1901