GrimmSpeed Aftermarket 3-Inch Downpipe to OEM Catback Adapter
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GrimmSpeed Aftermarket 3-Inch Downpipe to OEM Catback Adapter
Exhaust leaks are one of the most common headaches on a modified Subaru, especially when running an aftermarket 3-inch downpipe into an OEM or OEM style 2.5-inch catback. GrimmSpeed built this adapter specifically to solve that mismatch, using a flared transition that keeps flow smooth instead of choking it like many generic adapters do.
This listing covers the adapter only, designed to connect an aftermarket 3-inch downpipe to an OEM style Subaru catback. It suits both flat gasket and donut gasket setups, so it's compatible with a range of OEM and OEM-like exhaust configurations.
Note: This adapter is directional only. It connects a 3-inch downpipe to an OEM catback and cannot be run in reverse. Gaskets (3-inch flat gasket and OEM Subaru donut gasket) are sold separately.
Key Features
- CNC laser cut steel construction, hand welded
- Flared outlet sized just under 3 inches to maintain exhaust flow
- Flanged for OEM donut gasket compatibility
- Works with both flat style and donut style gaskets
- Includes mounting hardware for bolt on installation
- SKU: GRM077044
Vehicle compatibility, OEM part numbers, and fitment notes are provided in the tabs above. Please ensure your downpipe and catback configuration are confirmed before ordering.
Not sure if this adapter suits your build? Contact our team at sales@chicaneaustralia.com.au for expert advice.
Vehicle Compatibility
Universal fitment — verify dimensions before ordering.
Technical Specifications
| Spec | Value |
|---|---|
| Inlet Diameter | 76 mm (3 in) — aftermarket downpipe side |
| Outlet Diameter | Approx. 76 mm (3 in), flared slightly under full size — OEM catback side |
| Material | Steel |
| Construction | CNC laser cut, hand welded |
| Flange Type | Flanged for OEM donut gasket |
| Gasket Compatibility | Works with both flat style and donut style gaskets |
| Hardware Included | Yes — bolt on hardware included |
| Gaskets Included | No — 3 in gasket and OEM Subaru donut gasket sold separately |
| Directional Use | Aftermarket 3 in downpipe to OEM style catback only — not for reverse use |
No instructions available for this product.
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