

GrimmSpeed OEM Downpipe to 3in Cat Back Adapter
Subaru Turbo Models
Features & Product Details
RallySport Direct proudly carries a great selection of quality upgrades and accessories brought to you by GrimmSpeed.
This is the Grimmspeed OEM Downpipe To 3-Inch Cat-Back Adapter. This adapter is very popular for those of you who are retaining the stock downpipe and need to eliminate any exhaust leaks associated with the addition of an aftermarket 3" cat-back exhaust system. This adapter will allow you to retain your stock donut gasket to make for a great solution to eliminate the exhaust leak where the stock downpipe and your aftermarket 3-inch cat-back exhaust system will meet.
DETAILS:
Specifications
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REVIEWS & CUSTOMER MEDIA


Just installed yesterday afternoon on our 21 STi and checked for air leaks and none to note. Great fitment and snugs up to the donut gasket very well with the addition of our new exhaust. Great part from Grimmspeed! Please ignore some post as they are not referring to the correct part (this IS NOT an exhaust, it's FOR an exhaust IF you have a STOCK downpipe)
Wanted to wait a year before leaving a review. I purchased this for my son's 19 STI. First off, this exhaust is amazing in every way. V-band clamps are still holding up, no leaks and they stay tight. Welds are perfect, no cracks unlike another very popular brand that are made out of titanium. This car gets driven about 70+ miles a day, 20 miles of that is off road coming home. Hasn't rattled, cracked or broken down the blue tips one bit. If you're on the fence, check out Smeedia on youtube for a detailed install and sound. There is a very little drone, it is minimal and can be driven quietly if need be.
Worked just as needed to fit a turbo xs catback to my '06 Forester Xt. Just make sure you get a new donut cause chances are the old one is toast.
Perfect fit! Really thick quality. Came with hardware. 11/10 recommend if you have original cats and mounting a Tomei exhaust!
It was a perfect fit. No issues. 17 STi, Stock DP to Invidia Q300 cat back. I also bought the GrimmSpeed 2x thick gasket. I used the larger inner diameter gasket provided with the Invidia exhaust for the mid to rear section of he exhaust. Glad I bought the 2x thick gasket as I would have had to use the smaller inner diameter gasket for the mid section (had I used the larger provided one for the DP to cat back) and it would've created some restriction. Good buy!
QUESTIONS & ANSWERS
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Q: Exhaust Jey s.2 years ago
So I recently bought a tomei catback for my 2018 sti do I have to buy the grimmspeed adapter gasket to run the tomei exhaust
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A: Yes, this will allow your stock 2.5" downpipe to bolt to a 3" Tomei exhaust.
Lane H. @ RallySport Direct 2 years ago
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Q: Invidia r400 Ethanjprlta2 years ago
Just to confirm, does this adpator comes with gasket? and do i need it adapter for individia r400?
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A: A gasket is included, you would need an adapter to go from a stock 2.5" downpipe to a 3" cat back.
Lane H. @ RallySport Direct 2 years ago
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Q: Grimspeed catback adapter Josh2 years ago
Hello, I'm planning on buying the Invidia R400 Gemini Single Layer Quad SS Tip Cat Back Exhaust Subaru WRX / STI 2015-2020 and Invidia Catless Downpipe / J-Pipe Subaru WRX 2015-2020 6MT. Do I need the adapter since it wont be a stock j pipe anymore?
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A: No, if you are going to a 3" downpipe, you won't need an adapter to a 3" exhaust.
Lane H. @ RallySport Direct 2 years ago
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Q: Looking to buy this with the Invidia R400 - 2019 WRX alamsas3 years ago
Just wanted to confirm how many gaskets come with this product? I'm guessing the tapered side (female?) is where the oem donut gasket sits in between the adapter and the stock DP? The other side of the gasket is for the midpipe of the exhaust? If there's 2, I'm not sure what the other gasket is for. Wouldn't the invidia exhaust come with a midpipe to dp gasket as well? I'm guessing that goes in between the adapter and the midpipe? Thanks,
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A: This will come with 1 gasket, but you are correct in that the R400 will come with this gasket already, but Grimmspeed includes it just incase you don't have one. Hope this helps. Thanks!
Rick C. @ RallySport Direct 3 years ago
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Q: Gap between stock DP and Tomei SMsubaru3 years ago
when bolting up the tomei with the adapter and donut gasket to stock DP there is a gap between the two pipes. Is this just supposed to press against the donut gasket and be sealed? Ive got it torqued down pretty tight and doesnt appear to be leaking but it just looked weird to me
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A: Everything should sit flush. Reach out to us at [email protected]rallysportdirect.com and we can help you out!
Johnny M. @ RallySport Direct 3 years ago
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