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Square bore carb spacers

Smokinnjokin

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Gentlemen,
I'm putting a phenolic spacer under my edelbrock carb on an RPM manifold to help with the fuel boiling issue and I'm trying to determine if an open or 4-hole is appropriate for my application.

The engine is a mild 360, street car no racing. Its a low-compression, stoplight-to stoplight machine. I do put a decent amount of freeway miles on it also. Im reading conflicting literature about using a 4-hole spacer that preserves the separation between runners on the dual-plane, and using an open gasket to allow crossover. What are your opinions? Should I be running an open or 4-hole for my application?
 
Floats are set. Needles and seats are fine. The fuel is boiling off out of the carb after shutdown because it is too hot.
 
4 holes- with absolutely no hard facts to back me up. Keep the velocity up a little bit is my thinking.
 
4 holes- with absolutely no hard facts to back me up. Keep the velocity up a little bit is my thinking.

That is what I am running as well on my '66 Poly 318. With mine the '62 Poly cast iron intake also has the 4 individual holes though.
 
The RPM has the cut-down plenum so you can use whichever works best for you. I ran both on my 440 w/ RPM intake, they both worked great for insulating and added some response but you must re-adjust the carb. The effects of the open spacer came in a little later in the rpm range. I did, however, go back to the 4-hole since my car is a driver as well.
One thing to note- keep an eye on your throttle and kickdown linkages, you can run out of room real quick when raising the carb up. You don't want to end up with your throttle cable being pulled too tight or your kickdown to be at the very end of its adjustment range just to make things fit.
 
On the Chrysler small blocks , the Edelbrock RPM doesn’t have the cut down divider

That’s why I suggested that divided spacer
 
On the Chrysler small blocks , the Edelbrock RPM doesn’t have the cut down divider

That’s why I suggested that divided spacer
I didn't know that I thought all the RPM series did. Never used one on a small block though...Thanks
 
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