Anti Reversion Chamber on hexaust

[Desmoguzzi]

Dear All, some of you have any guide for the design of the anti reversion chamber? I see there are some parameters to play with but i cannot find any reference. For example what is best chamber volume, depth and diameter in relation to engine spec?

ar-muffler.jpg

[Tartilla]

What is your intent to achieve with the anti-reversion?

Performance Marine engines have massive issues with reversion, as it aerates the raw water in the exhaust, and draws it back into the exhaust port.

Pipemax has some good data that feeds out the tuning lengths etc for the various harmonics.

The best method to not have the exhaust revert, is having somewhere for it to go.

The anti-reversion chamber is going to mess with the reflected waves. Vizard has some good info on expansion chambers, that will act like anti-reversion.

[Erland Cox]

Whatever you try to do with the chamber there always seems to be pulses travelling backwards.
I tried an absorbtion straight thru damber and it worked much better than all the chambers i built.

Erland

[Dan Timberlake]

https://en.wikipedia.org/wiki/Tesla_valve

"It has also been shown that the device works better with pulsatile flows."

[MetricMuscle]

Dear All, some of you have any guide for the design of the anti reversion chamber? I see there are some parameters to play with but i cannot find any reference. For example what is best chamber volume, depth and diameter in relation to engine spec?

ar-muffler.jpg

The only parameters I'm aware of pertain to Pressure Wave Termination Boxes which use an anti-reversion type inlet. Inlet tube, end of collector, should extend about 2" into the chamber and the chamber DIAMETER should be at least 20% larger. Chamber volume should be 2x engine displacement. Chamber location depends on optimal collector length which takes priority over all other components.

Apparently chamber volume can include some of the tubing exiting the chamber but I don't know this is calculated.

[Tom68]

Dear All, some of you have any guide for the design of the anti reversion chamber? I see there are some parameters to play with but i cannot find any reference. For example what is best chamber volume, depth and diameter in relation to engine spec?

ar-muffler.jpg

Doubt that would stop reversion placed anywhere in the system. What you like to think will happen when you look at it is unlikely to be what actually happens.
I think the little chambers on the KTM 4t pipes just have a bleed hole in the internal pipe.

[modok]

For example what is best chamber volume, depth and diameter in relation to engine spec?

You should choose the engine to discuss. There is no exhaust rule that works on all engines.