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Old 08-25-2022, 03:59 AM   #11 (permalink)
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Originally Posted by Logic View Post
Well getting the engine up to temperature fast would help, but I do think lowering the exhaust gas volume helped too... if they didn't downsize the exhaust and muffler system too.

ie: Any exhaust can be considered more 'freeflow' if it only has to handle ~half the gas volume.
But the bean counters may have told the engineers to downsize the exhaust.
Cooling the exhaust might decrease scavenging with a normal header, which would result in lower volumetric efficiency. Or it might not. I guess it depends entirely on the tuning.

One thing almost universally agreed upon in the boy racer community is that these integrated-port heads really choke an engine's maximum power. Because the convergence points need to be much closer to the head, you can't tune for scavenging at all.

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