I have a 460 .30 over aluminum performer rpm heads and intake msd ignition and a holly dominator do i need a carb spacer?????????? or how do you tell if you need a spacer???? THANKS

 

I don't think anyone actually needs a carb spacer unless there's a clearance issue. That being said, typically spacers are used to help 'performance'...I'm not so sure about it though. But, 4hole spacers are typically used to help in the low end and open spacers are used to help the top end. The height of the spacer is supposed to play a factor as well, the shorter it is, it's supposed to help the low end (I never got this, why not just eliminate the spacer and be as short as possible) and the taller the spacer is, the more it's supposed to help on the top end.

 

Spacers can also help prevent the carb from soaking up heat from the intake manifold and boiling the fuel out...

 

You might find out that you have to run a spacer. Sometimes the carb can get so hot after shut down the fuel boils out of carb, just like furyus1 said. Which will make it very embarassing trying to get it started again if you are in front of alot of people. Ive done been through all that, I greatly reduced the problem after pickin up a phelonic spacer from jegs. I went with the 1in, open spacer.

 

From my understanding for the most part a spacer is always a good thing. Keeps carb cooler, and lets the fuel/air mixture mix together better.

 

cool thanks for all the help everyone spacer it is