Edelbrock Intake Manifold Dyno Test: Single vs Dual, Air-Gap vs Regular

In this video from the Westech Performance dyno room, comparisons are made between Edelbrock single-plane (Victor Jr) and dual-plane (Air-Gap) intake manifolds on the same engine. The video also looks at test results  between the Air-Gap design and regular dual-plane intake manifolds.

Seen on Car Junkie TV YouTube channel.


  1. Ray Johnson · March 15, 2013

    My setup consists of a mildly modified 351W with a Performer RPM dual-plane intake, a 2″ swirl torque spacer, and a 1406 carb. Would I benefit from a 1/2″ open spacer between the swirl torque and the dual-plenum? Thanks.

    • admin · March 15, 2013

      First of all, the #1406 is not recommended for the following intake manifolds: Performer RPM, Performer RPM Air-Gap or TORKER/TORKER ll. Do to its efficient/fuel economy design, customers can encounter a lean condition that may be challenging to resolve.

      Now to answer you question,

      It is always (in most cases) recommended to use only divided or 4-Hole style spacers on dual-plane intakes.

      Using an open spacer on these types of intake manifolds can compromise the effectiveness of such designs, and reduce bottom-end and midrange performance.

      So as a general rule, we would not recommend you use an open spacer unless you are only looking for upper RPM performance, and are willing to sacrifice bottom end/midrange.

      Please note: We (Edelbrock) have no test data on the swirl torque spacer mentioned. And do not offer one in our line of spacers and adapters, so it is challenging to comment on something you have not tested,.

      Please feel free to call our Toll Free Tech Line for further details.