Quote:
Originally Posted by dhirm5
Given that the downpipes on turbo cars are really just a piece of pipe with a couple bends in them, wouldn't it be cost effective to go to a good custom exhaust shop with a mandrel bender and have them fabricate something? High flow cats can be had for next to nothing:
http://www.mandrelbendingsolutions.c...,-High,/Detail
A downpipe should be a few hundred at most plus install time. What am I missing - why are these being sold for up to 3k for the F10 M5? |
I had MBS custom fab a catback exhaust for my old CTS-V (it actually droned to the point of giving me a headache) and before that they did a muffler delete for my old CL65 (which added a little bit more sound but no noticeable drone ).
The problem with the cats on the M5 is the tight space you have to work with in the downpipe area. The placement of the O2 sensors are pretty close to the inlet. The off the shelf catalytic converters will not fit in that area. I would also not recommend anything below 200 cells as you are likely going to trigger the CEL. You could try to use a "micro cat" up top to stop the CEL issue for a catless downpipe and then put two off the shelf catalytic converters down stream where there is more space (Supersprint has a set up like that but at an astronomical $ amount).