I spoke with Marco at AR Designs regarding the purchase availability for the catted and catless downpipes for the 535i n55 F10.
Marco said they will be available for purchase in 2 weeks.
He had no comment on price at this time.
In the meantime, a good question was asked by a member earlier in this post regarding the difference between an OEM catted down pipe and a catted down pipe from AR Design, RSI and/or Dr Euro, etc. Bottom line is that a catted down pipe from AR Design, for example, offers a greater diameter pipe and a far less restrictive cat than the OEM. The result is better air flow that allows the turbos to spool up quicker. The larger diameter pipe also allows the exhaust to exit the engine faster. And of course, this all results in better overall engine performance over the OEM catted down pipe.
Curiously, I asked him about the exhaust note. I wanted to know if one was to simply replace the OEM down pipe with the AR Design catted down pipe, while leaving the remainder of the OEM exhaust intact, would you here a distinct difference? He said there would absolutely be a more aggressive exhaust note, as a result.
Personally, I plan on purchasing the AR Design catted down pipe and a stainless steel or titanium performance exhaust system at the same time. I believe it would be reasonable to expect that there will be an increase in performance with an even more aggressive exhaust note verus simply switching out the OEM down pipe with the AR Design catted down pipe and leaving the remainder of the OEM exhaust system intact.
I like the idea of catted versus catless. I really do not want the hassle of dealing with the CEL light, potential warranty and dealership issues associated with the catless.
Last edited by Andy H.; 11-01-2012 at 10:01 AM.