Milltek Large Bore Downpipe & Hi-Flow Sports Cat - Ineos Grenadier B58 - SSXINE143

Milltek Large Bore Downpipe with Hi-Flow Sports Cat for the Ineos Grenadier B58

The downpipe is the biggest restriction left on a B58 once the rest of the exhaust is sorted. This Milltek large bore replacement opens it up to 4.50in (114.30mm) with a 200 CPSI Hi-Flow Sports Cat, built to pair with a Stage 2 tune on the Grenadier.

Key Features

• Large Bore: 4.50in (114.30mm) mandrel-bent T304L stainless.
• Hi-Flow Sports Cat: 200 CPSI catalyst in place of the restrictive OE unit.
• Fits OE and Milltek Systems: pairs with the factory exhaust or a Milltek Grenadier system.
• Tune Required: Stage 2 ECU tune required.

Technical Specifications

• Pipe Diameter: 4.50in (114.30mm)
• Material: T304L Stainless Steel
• Catalyst: 200 CPSI Hi-Flow Sports Cat
• Requires: Stage 2 ECU tune
• Fitting Time: 3.00 to 4.00 hours

Compatibility

• 2023 and later Ineos Grenadier B58 3.0 I6 Turbo Petrol

Why Choose Milltek?

Engineered for the Emotion.

Designed and manufactured in the UK with 40+ years of performance exhaust heritage. Nurburgring tested.

Specifications

• Pipe diameter: 114.3mm (4.50")
• Fitting time: 3 to 4 hours, including removing the factory system
• Off-road / competition use only. Not legal for use on public roads in the US.

Fitment

• INEOS > Grenadier > B58 3.0 I6 Turbo Petrol > 2023 and Later

• 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.