AR Design E89 Z4 35i / 35is N54 3" High Flow Cat Downpipes

AR Design 3" Z4 High Flow Cat Downpipes


This is a set of very high quality AR Design 3" stainless steel downpipes for the BMW 135i. They are 100% hand tig welded in the USA, and completely 304 stainless including the flanges and bungs. They are argon backpurged during welding to ensure full penetration and no sugaring on the inside of the pipe. This particular set is for downpipes with high flow cats.

We are extremely excited to present our 135i / 335i 3" Hi-Flow™ downpipes, now with Magnaflow race cats! The only TRUE 3" catted downpipes currently on the market! In addition to an intoxicating and exotic sound, these downpipes add significant power and virtually eliminate turbo lag, making the fabled N54 engine even more responsive!

Our Hi-Flo™ 3" Downpipes w/Race Cats Feature:

• The only TRUE 3" catted downpipes currently on the market! 3" tubing until cat-back flange - all systems currently on the market reduce to 2.5" much closer to the turbocharger.
• 100% hand crafted in the USA from premium 304 Stainless Steel (cats are made from 409 Stainless) - flanges and O2 bungs included!
• Water-jet cut 304 Stainless cat-back flanges, and CNC'd 304 Stainless V-Band flanges.
• Magnaflow 3" metal substrate race cats
• 100% TIG welded, argon back-purged.
• Set of our exclusive bomb-proof exhaust gaskets included.
• Grade 10.9 Metric Hardware (145,000PSI tensile strength, C32-C39 Rockwell, Zinc Plated), and Nord-Lock positive locking re-usable washers included.
• Factory location O2 bungs
• Available with a 2000°F ceramic coating. Coatings come with a 3 year warranty against corrosion and rust to original owner.
• Lifetime warranty against any manufacturing defects given to original owner.
• We do NOT grind/polish our welds as some other manufacturers do. Grinding welds compromises the strength of the weld, and can lead to weld failure! Especially critical in applications exposed to temperatures in excess of 1600°F. Such temperatures will also rapidly deteriorate the polished finish.
• NO CEL on pre 29.2 cars. Post 29.2 cars may require a DP Fix.

   We make no claims as to emission performance for street or highway use.  Some equipment is not sold for street use in any state or country where state or federal regulations prohibit its use.  Some items listed in the online catalog are intended for off road use and for purpose built race cars only.  EUROTEK TUNING, LLC does not make any claims of street legal use of these products that are not intended for use on public roads.  We do not ship any emissions related equipment to the state of California.  We require an off-road/track use only waiver completed, signed, faxed, emailed or returned to our facility before emission related equipment is shipped to customer supplied address.  We are not affiliated with Volkswagen Audi Group, Porsche AG or any of their subsidiaries.  EUROTEK TUNING, LLC is not responsible for errors on our website.