what size carb should i put on my 91 camaro 305, it will have an agressive cam and headers, nothing extreme. what would be a good size?

 

600-650 holley VS with elec choke id say

 

a 600 would be good.. vacuum secondaries since its not gonna be wild..

 

holley 600 cfm 4 barrel vacuum secondaries will be perfect

 

get a set of 31 tube shooters, cam kit, and secondary springs while you're at it...

 

If you really want vacuum secondaries, then invest in a Quick Fuel adjustable secondary diaphragm housing. It does it the right way, tailoring the opening by adjusting the vacuum signal, not the diaphragm spring. The spring dictates how much the secondaries will open, which sizes the carb to the engine size & RPMs, but that's not a good way to prevent bog. With the QF piece, you can use a weak enough spring to fully open the secondaries, which most any engine will support, while being able to control the secondary opening rate to prevent that initial opening bog.

Having said all that, I wouldn't recommend a vacuum secondary carb. If this is your final goal with the engine and car, then get a 600 double pumper. If you have future plans and want to keep the carb you get now, then I'd say hold off buying a carb until you do whatever you're going to do in the end.

BTW, if we can assume this started off as a TBI engine (which seems safe since it's an RS), your heads are going to limit performance more than any other thing in/on the engine. The size of the carb practically becomes moot.