
Milltek Large Bore Downpipe, Race Cat, Milltek Cat-Back - Audi TT Mk3 TTS 2.0TFSI Quattro - SSXAU604
Ships free in the US
- Shop tested in Dallas
- Free pickup in Dallas
- Installs at our shop
Milltek Large Bore Downpipe with 200-cell race catalyst for the Audi TT Mk3 TTS 2.0TFSI Quattro, 2015 to 2018, non-OPF/GPF models. This downpipe fits Milltek cat-back systems only. It does not fit the OE cat-back. The equivalent downpipe for the OE cat-back is SSXAU605.
76.20mm (3.0") mandrel-bent T304L stainless steel with hand-finished welds and CNC-formed flanges. The large-bore section cuts backpressure and improves scavenging against the restrictive OEM downpipe. The 200-cell race catalyst drops cell density well below the 500 to 600 cell OEM substrate for the highest flow in the range. Stage 2 ECU remap required to realize the gains.
Fitment & Compatibility
- Vehicle: Audi TT Mk3 TTS 2.0TFSI Quattro, 2015 to 2018
- Not suitable for OPF/GPF equipped vehicles
- Cat-back: fits Milltek cat-back systems only. Does not fit the OE cat-back.
- Catalyst: 200-cell race catalyst
- Bore: 76.20mm (3.0"), mandrel-bent T304L stainless steel
- Requires a Stage 2 ECU remap
- Direct fitment on OEM hangers and mounting points, no modification required
Part number SSXAU604. Choose SSXAU605 instead if the car runs the OE cat-back.
Designed and manufactured in the UK with over 40 years of performance exhaust heritage. Nurburgring tested.
Specifications
- Pipe diameter: 76.2mm (3.00")
- Off-road / competition use only. Not legal for use on public roads in the US.
Fitment
- Audi > TT MK3 > 2.0 TFSI Quattro > 2014 to 2023
- Audi > TT MK3 > TTS 2.0TFSI Quattro > 2015 to 2018
- Free US shipping on orders over $250.
- Free pickup at our Dallas shop, usually ready within 24 hours.
- Unused parts can be returned within 30 days. Tunes, opened electronics, merch and installed parts are final sale.
- Want it installed? Book the install at thegbmotors.com.
Full details are on our shipping and returns page.
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