So I got a stock carburator on a 84 z28 (manual transmission) and I got a stock carb on it and I wanted to upgrade it, but what something that will fit exactly into my car??my budget is about $200-$300, just really depends on what the carb can do for me performance wise...

and I know this question mite sound dum but what exactly does a aftermarket/performance carburetor do for me?thanks! Will I actually notice the difference? and is there any else in that price range that I can do to gain some HP?thanks!

 

If your car still has the computer controlled quadrajet, having that rebuilt would be your best option.

 

For $200-$300, you won't be able to do anything if you are buying new parts.

Since you have a manual transmission, a double pumper carb could be justified. But, there isn't anything that will "fit exactly". This will bolt to the intake manifold http://www.summitracing.com/parts/HLY-0-6210/ but the choke is going to be an issue.

The advantage of a double pumper carb is the throttle blades close when you let off the throttle, and open when you floor it. With a q-jet, there will be a slight delay, especially between gears, for the secondaries to reopen. It's the opposite with vacuum secondaries - they don't close right away when you let off the throttle (which can be "interesting", to say the least).

For $200-$300, the stock carb is your best bet. You could put on an aftermarket intake like a Performer or Action +, but that's about it. The performance benefit will be small, if perceptible at all.