I showed these to the motor heads at work because I did not understand why they ported the dual exhaust into a single one.

They had a white board full of visuals in no time flat explaing how putting them into a Y actually gave back pressure and gave more low end torque to the engine...

Then they explained whey all the ricers with the fart can's make that bog sound at low rpm's (increase of flow stops backpressure and they lose the low end torque). So they basically warned me about after market exhausts...

It was probably the most interesting coversation we have had in our lab for a long time.

thanks!

-marc