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juxsa
06-22-2009, 12:15 PM
any one know what kinda bends are on a b5 a4 quattro? I am going to hav emy local exhaust shop do an exhaust for me and I was thinking about getting a mandrel bent kit from here:

http://www.mandrel-bends.com/catalog/builder-kits-33/

don't want to buy to many bends but don't want to buy to few. which kit do you think would cover it?

dcampana
06-22-2009, 12:27 PM
if you are having a custom exhaust done they should have a mandrel bending machine. i would have them do it. I looked at mine and there are a lot of small degree bends that none of those kits seems to show.

just my .02

AudiRacerS4
06-22-2009, 02:29 PM
if you are having a custom exhaust done they should have a mandrel bending machine. i would have them do it. I looked at mine and there are a lot of small degree bends that none of those kits seems to show.

just my .02

x2

juxsa
06-22-2009, 02:44 PM
you would be surprised that most exhaust shops do not have mandrel benders. I would likely have to drive a few hundred miles to atlanta or nashville to find a shop that has one. I may just stick with compression bent pipe

dcampana
06-22-2009, 03:00 PM
that should be fine.. I am sure the differences are not that big from a performance perspectitive. I am lucky enough to have 4 shops here local that all go mandrel bent so I assumed. Sorry man... But seriously dont think the compression bent pipes would be a big issue.

juxsa
06-22-2009, 03:02 PM
I had a 3in exhaust on my turbo dodge and it was compression bent and it didn't look like it lost much flow. I figure it should be fine. Now I just need to find a good muffler and a resonator.

andyrew
06-22-2009, 03:27 PM
Go to the shop, have them put it on the lift for an estimate, take some pictures and find out if they carry mandrel tubing or have their own bender. If not then use the pictures to determine your bends or simply ask THEM.

dcampana
06-22-2009, 04:44 PM
I have a dynamax ultraflow 3" in/ out.. no droning at all. seems quiet until I am at WOT....

B5A4Kevin
06-23-2009, 05:31 AM
a lot of shops have compression benders with flexible inserts, (similar to mandrel, but not as close tolerances), to avoid distortion at the bend area.

one thing i learned at school (uti/nti) was pretty interesting, was (especially) in the case of multiple bends, the total length of the pipe actually shortens a little bit. theres a formula i have somewhere to calculate it, but when it comes to roll cages and tube frame chassis, you have to be exact with your calculations, otherwise your bends may be in the wrong place, or the welding locations wont line up properly.

h4robkr123
06-23-2009, 08:08 AM
I run a compression bent bent 2.5" catback and I can definitely see where it would lose flow, but it's not a huge amount by any means.

A4-Achtung
06-23-2009, 02:22 PM
I couldn't find anyone in reasonable distance that does mandrel bending.... Texas sucks!