Open or Four Hole Gasket/Spacer on Edelbrock AVS2 Carburetor?

[boboh1]

I have a stock intake manifold on my 383. Installing an Edelbrock AVS2. Would an open gasket and spacer be better than the four hole type?

 

[GTX JOHN]

I use a 4 Hole on an intake that has 4 (or2) holes.
I use an open on an intake that is open plenum.

 

[66 Sat]

You have to match the manifold as GTX John suggests. Otherwise the fuel distribution/velocity will be upset.

 

[T Brashears]

I have a plastic 1” 4 hole on my DP4B for the heat. 4 holes to keep the signal stronger at low rpm’s. Check the holes in your spacer/insulator of choice,
I had to hone a slight bevel in the top of the holes in mine for clearance.

 

[AR67GTX]

You have to match the manifold as GTX John suggests. Otherwise the fuel distribution/velocity will be upset.

And it may whistle loudly too from air leaking across the intake bores.

 

[33 IMP]

Engine masters spacer test seemed to show that an open spacer worked best on a dual plane manifol, and a four hole spacer worked best on a single plane (opposite of GTX John's results). Why.not try both, and sell the one that works the least.
(I ran a 2" open aluminum spacer on a single plane intake, with an 850 dp, but never ran without it, so I have no idea if it worked, or not).

 

[boboh1]

Thanks for the input. I’ll go with the four hole match. The new carburetor came with the open gasket so wasn’t sure if correct or not for stock intake.

 

[Geoff 2]

Never use a 4 hole gasket [ talking about a thin 1/16" gasket, not a spacer ] on a 2 hole intake. The unsupported gasket could blow out if the engine backfires. Make the gasket into an open gasket, even with a 4 hole intake.