Stock fuel pump limits

If you dig into the specs for the current replacement Carter pumps (that are priced at $25-30), the spec is 25 GPH max at rated output pressure, which is not good enough for 350-400 HP. But I suspect many will do 30-35 GPH; 35 GPH is good for 400 HP. The higher performance Carter pumps like M6270 (and M6902 if you can find one) are good for the 50-60 GPH range at rated pressure. With these Carters, watch out for the pressure of the M6270; it is above the pressure range for a lot of carbs, so a regulator is needed.

BTW, the Summit descriptions of these Carter carbs that they will flow 120 GPH at rated pressure are wrong. 120 GPH flow is the free flow rating.