will a one inch carb spacer do much?

 

The phenolic ones absorb a lot of heat between the carb and manifold, but other than that I didn't notice any performance gain/loss when I switched from a 1" to my 5/8" nitrous spacer.

 

If you don't have a spacer, adding a spacer will make it idle a little smoother.

As stated, not only will the spacer insulate the carb from the heat which can cause vapor lock and lower density air, it allows the air/fuel mixture to atomize a little better since there's a bit more distance.

 

and depending on which once you get they do different things

 

These are suppose to help give you a little more on the bottom end depending on you're setup. However with that said, if you have a near perfect match with all you're components (like the heads, cam, crank, carb and so on) the deference will be negligible.