[Steve C.]

Cliff, I don't quite get this one.... "Steve, to "rephrase" your last response: "I don't care how well it idles, or if my new high performance parts slow it down at the track, I can always make the new parts work with more converter and/or gearing".
I've never been able to explain it as well as you do but my point was that often we need to make adjustments to optimize a parts selection, in this case a switch from a dual-plane to single plane intake. Often a looser converter will help the situation or a more gear. Did I get it wrong ?

Example on my car. As expected when we dyno tested my previous 462 it made more horsepower at a higher peak power rpm with the Victor intake than w the Performer RPM intake. And when we took the car to the track with the Performer RPM intake it ran much faster with a looser 8-inch converter than with my tight 10-inch Contemtial converter I had at the time. I knew the Victor intake would run better than the RPM intake but only with a looser converter installed, so I elected to run it with the RPM intake for the most part because I felt my Continental converter was better. This was quite some time ago, now today Continential has the ability to make way looser converters (3500-3600 and up stall) that couple well out on the street. Today this new type of Contential converter might be the hot ticket for my old combo with the Victor intake.