My friend has a shop literally a stones-throw from the KB shop in Mooresville which is right next to an 1/8th mile drag strip where they do a LOT of 60' Testing.

The first thing you note is the KB cars seem to be out 60' everybody so their MPH advantage may not be ALL top end HP. Mooresville is the hotbed of American Racing technology, besides NASCAR there is also the Ganassi F1 and FORD dumped a lot of R&D into the GT-40 LeMans effort in Joint development with Ganassi Racing. A number of the race teams have some pretty mega databases for simulating engine variables that could greatly reduce the R&D/guesswork development time. There's quite a good supply of very clever motor guys up in these parts to say the least.

Also it's not only the intake mainifolds, KB may have also been on the leading edge of optimizing the entire intake tract and cam timing. At Z-Max in Charlotte you couldn't help but notice all the manifold covers on the KB cars, and it made me wonder (somewhat at what Monte hinted at) that maybe it's a bit of Rope-a-Dope and they found 'something else'

Still at the same race all the MoPar intakes were exposed (at least nothing they were hiding with the new cars facing forward Pit rule) and on display and it looked to me like they were trying several different configurations, one of them was rather small and compact with a number of ribs that made it look like a Jack-O-lantern, lol.

It does seem like Roy and AJ may be slowly closing the gap, they've been there before, wasn't that long ago when the KB boys were using the (now Illegal) '85 degree' motors that were 90 degree banking but the thrust sides of the bores were angled 2 1/2 degrees away from the crank (as measured from top to bottom) to reduce friction on the power stroke, that was a NASCAR trick someone tipped them off to.