Best J intake

[bowtieluvr]

Which J intake manifold is best for performance ? There is a Dual plane (with divider) or a single plane (open in the middle). is there any performance benefits from one to the other. On gassers (which have a wet intake) it is commonly known that the dual plane type intake is better for lower end grunt and the single plane type are better for higher RPM. Since on a diesel the intake is dry (without fuel) this could be different. Not sure? Anyone have experiences? Also their is the Hummer intake which appears to be a single plane. Anybody seen these all tested on a dyno? I bought a single plane J to swap with my dual plane J but was wondering if it will make much difference.

[EWC]

When I had my heads ported , we tried both the single and dual plane intakes ( non Hummer ) after porting . The single was worth 20 CFM over the dual plane .

[john8662]

IMOH, the single plane looks the best for flow, but I really can't say that the single plane intake flows so much better than the dual plane.

The most restriction into the intake manifold is going to be the small hole into the air cleaner housing. You want more air? Either stick the TURBO on or do a Dr. Lee airbox!

[4.3dieseljeep]

I have tried bolth, and the single plane is better across the entire rpm range.

[bowtieluvr]

All,
Thanks for the replies! I am planning to perform the swap soon as it sound to have a positive outcome.