MK4 twin system exhaust - possible?

[kenny21]

Didz - Backpressure is a myth - You do not want backpressure under any circumstances, even with an NA motor. And besides, a couple of extra tips coming out of the same muffler would have no affect on anything.

Backpressure is not a myth. You do need some but at the same time not a massive amount. Otherwise you could put a 5" straight through exhaust on your car haha, i know im exagerating a bit, but its just an example to say backpressure does make a big part in torque figures high and low end.

Cheers

Alex

[99gti]

I'm lead to believe the turbo will produce most of the back preasure that's required as it also acts as a muffler too. I would have thought having a bit of back pressure beyond the turbine would also help generate force to spool the turbo faster?!?

Note: I just heard this - not sure how true it is but it kinda makes sense too...

[torque]

Nah; backpressure is a myth. The quicker and faster you can get your exhaust gases out of the engine the better for a turbo car.

You never need backpressure; ever.

[SoVeReIgN]

Backpressure is not a myth. You do need some but at the same time not a massive amount. Otherwise you could put a 5" straight through exhaust on your car haha, i know im exagerating a bit, but its just an example to say backpressure does make a big part in torque figures high and low end.

Cheers

Alex

Nope - Backpressure is a myth - Idealy you want zero backpressure.

However - The reason you don't have cars getting around with a 10" pipe is because exhaust gas can cool down within the pipe and this makes it slow down. (Fluid dynamics 101)

So, you want the biggest fattest pipe you can have without being too big as to have the exhaust gas cool down as it goes through it.

[kenny21]

Do u have anything to prove on paper to say that backpressure is a myth or worked and done research on exhaust systems, because i really dont think that mechanics from formula 1 and many other racing categories would talk about backpressure and make it such a big issue with making exhausts ie 4-2-1, 4-1 etc etc if it was just a myth.