Not Ranked
I wish I had the answer to the crater in the curve. I think they mentioned in this months Popular Hot Rodding article that we ran into a "twilight zone" quality issue on the dyno. The engine ran smooth and solid all the way to 6500 - - and it was a pooch - - down by 100 from expectations. Though we eventually found the problem (a coil) it killed us a full day for tuning time.
I can tell you that the hole is entirely insensitive to timing and fuel changes - - we had the A/F all over the map, and ended up with a very smooth 12.5:1 as a reference for the contest itself. We also tried a variety of carb spacers that only seemed to push it around a bit. With more time we'd have tried a different cam. We also would have tried some header options - - seems the rules guys were flexible - - with others using smaller or venturi collectors (I saw a bunch of 3" stuff on applications where I know they would ship with 3.5 like I had).
Next year's contest is 434" so I expect that the package will change a bunch...
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