Carb spacer input required

[big2bird]

Scott wants me to add a 1" spacer to his set up. It is a 400HP 350SBC.
With this dyno sheet:

And this 750 DP holley carb

And this Edelbrock dual plenum manifold.

Which of these spacers (Inserts)would give the best benefit?

I was leaning towards the open spacer, but now am thinking the 4 holer would be better.

 

[guru]

The HVH spacer is supposed to be pretty good.

 

[MYBAD79]

Same AutoZone spacer that I bought.... it keeps the drop base air cleaner bottom from hitting the wire boots on the distributor, other than that I have not noticed a difference between open, 4 holes or no spacer..... oh yes, my wallet is $20 lighter.....
:huh::bounce:

 

[Twin_Turbo]

put in a turtle (no joke!!!)

 

[big2bird]

After discussing it with Lars, I believe I am going to use the 4 hole setup. It would appear the open spacer would do more harm than good with a divided plenum. Unless Scott wants to run above 7,000RPM. :nuts:

 

[kwplot34]

I have thought about buying these and installing them in my Brodix intake,but i have never met anybody yet that uses them to get any input. what input do you have TT :fishing:
http://www.brodix.com/parts/turtles/turtles.html

 

[Twin_Turbo]

Bird can't use it because he has a dual plane, and they won't fit on a single plane with a divider. They're for specific manifolds and each one is different but since it's called the turtle I thought I'd mention it here. Who would have thought, a performance upgrade called turtle Jim may have something going for him afteral :1st:

I never used one, read about it some time ago.

 

[guru]

HVH makes a blended spacer for dual planes.