LD340 v/s Edelbrock Air Gap

Mattax said

John may be able to speak better to this but the LD340 has large volume runners compared to the RPM.
I suspect the narrower cross section of the RPM runners better maintains velocity under low flow (low to mid rpm and part throttle) situation. FWIW it has been reported that the RPM made for brand C favors certain runners at high rpm.

I have an RPM to try out instead of the LD340 but never get around to actually doing it....

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The "favoring" of certain runners at different rpms is what all dual plane manifolds are designed to do. Longer runners help lower to mid rpm torque, and shorter more direct runners favor mid to high rpms.
Article writers seem to think the air gap is the end all be all. I am wondering if it is because it is what their advertisers currently have available for sale and whether or not the LD340 can hold its own.

I like that the LD340 can be modified to use a thermoquad for street duty. Just wondering what if anything is being given up using it on a stock stroke 340 or 360 in a high compression build with headers, cam, and a decent set of heads.