Ive got an 85gmc Sierra 1500 im looking at
swapping it from the stock quadrajet carburetor to
a better carburetor, just wanting some opinions on
which one would be best and most efficient for the
350 motor thanks in advance!!
Holley 600cfm would be a great choice
A Quadrajet if it is setup properly is a good carb for good all around performance and good mileage if you keep your foot out of them, second place would be an Edlebrock, you can fine tune them with different metering rods and jets, but it takes some trial and error, third would be Holley, they can be a little finicky about adjustments, the right power valves, jet sizes, but you do have a choice of single or double pumper, something the others don't even offer. Now if your really into getting performance and good mileage then look into replacing it with a fuel injection unit that bolts right on to your stock manifold, they are expensive but highly tuneable.
If it is stock I would go back with the same quadrajet or an elderbeock a holly would be my last choice if it is stock
My only issue with sticking with the quadrajet is the quality of the carburetor
Then go with an Edlebrock.