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Old 10-04-2022, 06:17 AM   #15 (permalink)
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Originally Posted by serialk11r View Post
I don't think exhaust reversion is a huge issue other than at low load + low speed (I read a bunch of papers about exhaust reversion trying to figure out how to optimize my VVT).

At low load, you're pretty screwed because the intake pressure is far far below atmospheric.
Yep. But low load and rpms is what most here are doing.
And doing so without a Branch specifically made for low rpms...
So think the anti reversion doodats will help some.

If you really want to stop ALL reversion of exhaust into the intake tract:
Put Reed Valves (Carbon/Glass Fiber), on the intakes, as close to the intake valve/s as possible:

This allows the use of an extremely 'hot' intake cam, but gives you infinitly variable intake cam timing... Exhaust cam too, to some (overlap) degree...

Honda uses/used them in their 500cc single cylinder 'Thumpers'.
Alfa Romeo experimented on car engines:
Lost ~1kw in top end power, for VASTLY improved low rpm drivability.

Last edited by Logic; 10-04-2022 at 06:40 AM..
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