I was thinking SM vs the Eddy RPM air gap .. but I'm sure the RPM would flow more as well. I think the SM intake (I've used 2, have another new in the box still) is great for a stock or near stock engine. A great, cheap way to put a carb on a magnum, or a 4bbl on a LA. But I do not think it's the intake of choice once you start North of 400 hp