LD340 manifold vs RPM Air Gap

From what I have seen reported is there will be very little difference. The normal recomendation is if you have an LD340 the cost of the RPM is not worth the small perfromance gain.

The Airgap will be more cold blooded than the LD340. In 40 degree weather it takes a couple of miles for my car to warm up enough to be happy. In 20 degree weather it can be 5 or more miles.