1971 360 question

unless your running high rpm /big cam 750 is big

Not necessarily at all. I run a 750 double pumper on my stock stroke 340. I tried everything from 670’s to 870’s on it, the 750 double pumper with mechanical secondaries is by far the best fit, confirmed with an afr gauge as well. Just a street car, moderately sized cam but by no means “big”.

750’s on a 360 with a decent cam/build is very common.