glasspack mod

[wiplash123]

 I instaled glasspacks on my 2000 Interstste how can I tell if I have enough back pressure or not?
I can tell she lost some power I used a 3" to 2" reducer with the 2" coupling with the purple honey glasspacks.

[Mr.BubblesVRCCDS0008]

I've been running the purple hornies for several years now and the lady runs like a top. At this moment I don't even have the mufflers in, just the reducers and straight 4 in pipes.  Yes it is loud but my hearing is failing so it doesn't bother me.

[98valk]

the best exhaust system is "zero back pressure", but it must be sized correctly to keep the velocity up. so high velocity, zero back pressure is the best. u don't want back pressure.

[Dodis]

Yes, no backpressure is great, but some scavenging will help too. In my exhaust, I can feel the difference between my glasspacks (2"), the straight pipes (2 1/4"), and just the reducers. Just butt dyno readings...

Properly setup for scavenging, as I understand it, has the momentum of the exhaust flow creating almost a suction to help pull the exhaust out of the cylinder that is just opening it's valve. In mine, I start losing that with the larger straight pipes, and even more without any pipes. I plan to try some 1 3/4" pipe and see how that does compared to the glasspacks.

Mike "Dodis"