[78 Chevyrado]

only thing quadrajets have, tho it's a big plus, is the super tiny primaries. otherwise they're nothing special. thats the sole place their economy comes from, (assuming you dont open the secondaries regularly).

The main reason people dont use q-jets more is the parts to tune them are expensive because they are relatively rare. everyone says to get a holley because thats the most common carb to buy parts for. (im not saying anything bad about q-jets or holleys)

holleys seem to have more fine tuning, and easier, plus parts are common and cheap.
Edelbrocks are more the set it and forget it carb (at least in my experience)
and q-jets are OEM, have small primaries for fuel economy but tuning parts are rare and expensive. also this is a set it and forget it carb (in my experience)

every holley ive ever had, up to about 1998, required constant tinkering. when I've had Q-jets or edelbrocks, once you set it, that was it, it was good for years. i only had to adjust them some for the temp change between 100 degree summers and 10 degree winters. all the holleys i had had to be tinkered with constantly. ( as in at least once a week, when i was already late for work).