[454headache]

Would there be any benefit in putting a carb spacer on a dual plane manifold? I know that an open spacer would potentially increase top end at the expense of lower end. But would putting say a 1" 4 hole spacer provide any benefit? The manifold is an Edelbrock dual carb (600cfm vacuum secondaries) and dual plane (4 hole) manifold. Or, since my carbs are set up to be progressive, what about a 4 hole spacer one the primary carb and a open spacer on my WOT carb?

The engine is a very mild 454 9:1 compression in a heavy C1500 truck.

 

[DoubleVision]

My thoughts are you need more carb! Anyways, if I was going to fool with any carb spacer it would be a super sucker by HVH.

 

[sqzbox]

4 hole 1in spacer for the primary carb, good idea. Open spacer on the secondary, bad idea. If you have a dual plane 4 hole dual carb intake, putting an open spacer on the secondary 4 hole is going to make some restriction in the airflow under the secondary carb.
I might get in trouble here but, Auto Zone has a 1 in. spacer that comes with an insert with 4 holes or an open type. You can try it your way and if you don't like it, you can remove the open insert and put the 4 hole back in as they are removable. I bought 1 two weeks ago for 21 bucks so, for 42 bucks you can get your 1 in. spacer and not get hurt. I also comes with all the nut's and bolt's you'll need for installation. :thumbup: