
MilltekSKU: SSXINE145
Milltek GPF/OPF Bypass - Ineos Grenadier B58 - SSXINE145
$445.00 Available
Ships free in the US
Make sure this fits your car
Fits: Grenadier B58
1
- Shop tested in Dallas
- Free pickup in Dallas
- Installs at our shop
Milltek GPF/OPF Bypass for the Ineos Grenadier B58
Replaces the particulate filter section on the Grenadier B58 with a straight T304L bypass, removing its restriction and sharpening the exhaust note. Fits the OE or Milltek downpipe and any OE or Milltek cat-back or OPF/GPF-back.
Key Features
- Straight Bypass: 3.54in (90.00mm) T304L bypass pipe plus connecting pipe.
- Fits OE and Milltek: works with OE or Milltek downpipes and cat-back or OPF/GPF-back systems.
- Tune Required: Stage 2 ECU tune required.
- For closed-course and competition use only.
Technical Specifications
- Pipe Diameter: 3.54in (90.00mm)
- Material: T304L Stainless Steel
- Parts: GPF/OPF bypass pipe, bypass connecting pipe
- Requires: Stage 2 ECU tune
- Fitting Time: 1.50 to 2.00 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: 90mm (3.54")
- Fitting time: 1.5 to 2 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
Listed for these cars. Check the title and description for exact years, body styles and drivetrain.
| Make | Model | Chassis | Years | Fits |
|---|---|---|---|---|
| INEOS | Grenadier | B58 | 2022+ |
Not sure? Call or text 945-954-1142 with your car or VIN.
- 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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