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Originally Posted by serialk11r
It wouldn't be cams, a high strung cam has limited VE at low engine speed because it ends up pushing charge out of the cylinder. Intake tuning + intake cam advance can attempt to fix this but you're going to be limited by the exhaust gases "poisoning" the charge.
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You say "It wouldn't be cams", then go on to describe exactly why it probably *is* the cams.
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Because the cam appears to be a high rpm cam, there are no variable intakes, the torque down low approximately matches the torque peak, and the peak torque is quite low by performance engine standards,
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143 rw lb-ft out of 2.0 liters is pretty tremendous, actually. Scaling by the same amount to equate 173rwhp to get 200hp at the flywheel, we get 165 lb-ft at the engine, 83 lb-ft/liter!
2.0 S2000s typically put ~135 lb-ft to the wheels.
[edit]Oh, wait, looks like you might mean that the peak torque *rpm* is low. IMO, peak torque rpm is usually a useless number. The engine pretty much makes the same torque from 2600-3200, and then from 4600 up to 6400rpm. It's not like they tuned for maximum torque at 3000. The tiniest, most real-world meaningless wiggle up top would change peak torque rpm from 2800rpm to 6400rpm, without changing the character of the engine's output.
Logical conclusion to me is: They good job maximizing power from 2.0 liters and limited to 7400rpm peak while also giving good low-rpm driveability.
I've seen "the dip" on a ton of dyno graphs, IMO it's a low V.E. region due primarily to cammage.
I don't see the dip as a problem, nor do I see it as something that's going to be easily gotten rid of...