Backpressure

[Dave Harryman]

I know Im new here so let me tell you guys that Im not new to building engines for more power , I am a engine builder / machinist / fabricator , here are a couple pics of some VW engines I built back in the 80's ,you cant buy these parts , they are hand made , not trying to brag ,just trying to let you guys know I have a lot of experience when it comes to hot rodding stuff this one had Porsche Hemi heads and overhead cams fitted

[Kainam]

Nice!

[chris_lacey]

Originally Posted by Dave Harryman

does the thunderheader antireversion cone have a baffle ? and by baffle I mean a component that restricts flow, because that is what I designed and it drastically reduces noise with virtualy no power loss

Yes, see for yourself here:
Thunderheader X-series Exhaust

[Hillsidecycleco]

It is not about "backpressure", but rather the ability to CORRECTLY control the reversion.
Scott

[Dave Harryman]

Originally Posted by chris_lacey

Yes, see for yourself here:
Thunderheader X-series Exhaust

thanks for the info , looks like that is how it can be done on a meg ,has anyone dynoed it back to back against a empty one and do they say how many DB it lowers the noise output ? ....anyway my design is for glasspack type mufflers not megs , and it lowers full throttle noise output drasticly with only a .5 peak HP loss , it makes an overly loud open system pass the FIM/AMA sound test on the dirtbikes we run them on

[Dave Harryman]

Originally Posted by Hillsidecycleco

It is not about "backpressure", but rather the ability to CORRECTLY control the reversion.
Scott

that is what I was trying to say