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GrimmSpeed OEM Downpipe to 3in Cat Back Adapter

MODEL # GRM077046

$57.00


54 Reviews
4.9 out of 5 Stars
5 Stars
(49)
4 Stars
(4)
3 Stars
(0)
2 Stars
(0)
1 Stars
(1)
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GrimmSpeed OEM Downpipe to 3in Cat Back Adapter  ( Part Number: 077046)
GrimmSpeed OEM Downpipe to 3in Cat Back Adapter  ( Part Number: 077046)
2.5 to 3in exhaust adapter 8 months ago
5out of 5stars
mrmrs_sti
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)
  
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0 of 1 people found the following review helpful
Amazing sound and build quality!! 2 years ago
5out of 5stars
Mike D Sr
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.
  
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0 of 1 people found the following review helpful
Excellent! 3 years ago
5out of 5stars
Nick
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.
  
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1 of 1 people found the following review helpful
Perfect fit 3 years ago
5out of 5stars
11/10 recommend if you get a Tomei with stock cats
Perfect fit! Really thick quality. Came with hardware. 11/10 recommend if you have original cats and mounting a Tomei exhaust!
  
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1 of 2 people found the following review helpful
Perfect fit 3 years ago
5out of 5stars
Holywowcow
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!
  
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Works as it should 4 years ago
5out of 5stars
WheelJack
Not much to say other than it's an adapter and works as intended. Grimmspeed always uses quality hardware - glad to see Grade 8 bolts in the packaging.
  
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Does it what it claims to do 4 years ago
5out of 5stars
BIGWNG
I used this while installing a Tomei Expreme Ti on a 2019 WRX STI. It functioned perfectly. I highly recommend!
  
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Easy to Install and Fits Great 4 years ago
5out of 5stars
Ultra_Deku
This was very easy to install for someone who has never done an installation like this before. I installed it on my 2018 WRX when I was swapping the stock exhaust for an Indivia Gemini. No leaks, and everything fit together perfectly.
  
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Works great  4 years ago
5out of 5stars
Sam French
Installed an Invidia N1 on my 2011 WRX, and had a leak from the downpipe to the midpipe. This plus a donut gasket and about 15 minutes of time fixed the leak extremely well. Definitely recommend if you want to install a 3” catback on a stock downpipe
  
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Excellent Product! 4 years ago
5out of 5stars
Ozzy V.
A must have for anyone running a catback with the OEM downpipe! Hardware is top notch as well!
  
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Perfect  4 years ago
5out of 5stars
FozzySchu
If there is one thing that makes me the happiest, it’s parts that do what they are meant to do. Made it a dream to put my cat back on! Thank you!
  
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Perfect 4 years ago
5out of 5stars
Chris
Great part worked great no leaks
  
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It Works 5 years ago
5out of 5stars
Fox
Nice gasket that does the job between the oem downpipe and my new ETS catback. It provides the proper sealing of exhaust gases and includes nice hardware. The oem hardware did have nice springs to allow for flex, which the Grimmspeed does not.
  
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1 of 2 people found the following review helpful
Make sure you need it before you buy it.  5 years ago
5out of 5stars
GeorgeV
I was told and read that you need this to bolt up a cat back to your aftermarket stock style downpipe. No. You don’t. You only need this is you’re bolting a cat back up to the STOCK downpipe. So while I love grimmspeed gaskets etc I really didn’t need this.
  
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Perfect fit 5 years ago
5out of 5stars
Paul
I ordered this adapter with my Tomei Expreme Ti purchase for my 2017 Subaru STI. It fits perfectly from the downpipe to the catback. I would recommend this adapter over the provided gaskets from Tomei.
  
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Saved my install 6 years ago
5out of 5stars
FranklinWaters
The shop that installed my Invidia N1 race exhaust ended up cutting off the flange for the stock downpipe and welding this on to install the CBE. It made the install easier and would have made it easier for me if the level of rust did not cause me to take the car to a shop to do it.
  
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GrimmSpeed OEM Downpipe to 3in Cat Back Adapter 6 years ago
5out of 5stars
Zackm161
Simple and simplifies installation of catback exhaust to OEM downpipe.
  
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Easy install 6 years ago
5out of 5stars
Booshwacka
Part fit perfectly on my 2014 WRX Hatch. Stock downpipe to Tomei exhaust. Been using it for 2 weeks now. No Leaks. A+
  
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Very satisfied!  6 years ago
5out of 5stars
CarlosWrx
Had the stock downpipe, needed this adapter for my Invidia q300 exhaust fit perfect!
  
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Get a Donut! 6 years ago
5out of 5stars
Boostaru29
Great adaptor. Makes installing a Catback to OEM downpipe or to a Cobb Downpipe a breeze. Don't be stingy like me and skimp out on the donut gasket. I got the OEM catback off and broke the donut gasket in 2 pieces. was 8 at night so couldnt complete the swap until the morning. I live in a small town and had to stop at 3 different places to get another donut gasket the next morning. Take my advice. spend the extra money and save yourself the hassle of driving around looking for a donut gasket.
  
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A necessary inconvenience 6 years ago
5out of 5stars
vash337
Having held on to my GS '3in dp to stock catback' adapter from my last car, it was inconvenient to discover I needed this piece which came to 60 bucks with 2 day shipping. But it's necessary for an easy install. Just bite the bullet and get it. I plan to hold on to both for the future instead of possibly repurchasing.
  
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Indispensable for OEM or Cobb downpipes!  6 years ago
5out of 5stars
NickyG
If you're running a Cobb or OEM downpipe mated to a 3" exhaust, this is the only adapter you need for a leak-free connection. Burly construction and nicely machined. It bolted right up and has been leak free. The bolts are ridiculously long, but this does not impact its functioning. GS makes really nice stuff, and this adapter is an excellent example. Highly recommended!
  
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Thick 7 years ago
5out of 5stars
Silverfoz93
I didn't do the install I had some one else do it due to a lack of tools. I test fit the adaptor to a invidia g200 for a 04 fxt and it was a good snug fit. I watched the install closely the tech Had no issues with fitment.
  
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Looks great and works even better 7 years ago
5out of 5stars
Simply Stu
Bought this along with my Invidia Q300 CBE for my 2015 STI. Looks amazing, and is made from high quality aluminum. Install was a breeze, I also bought a new donut gasket to get a fresh seal. The only thing I didn't use out of the box, were the nuts. I opted to go with copper nuts instead of the supplied ones, just for extra security. And I also used washers to fill in the gap between the two flanges. Also a big notice will be that bumper clearance will change a bit, due to the added extra 1/2". Worth the money, and so far with 1000K in there are no leaks at all.
  
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J Reynolds 7 years ago
5out of 5stars
J Reynolds
No problems. You should tell those ordering a cat back system that this adapter is recommended. I had to call, after getting my Q300 system, to clarify that should have the adapter.
  
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downpipe  7 years ago
5out of 5stars
boosted12
Great product good price if you have a oem downpipe and a cat back then need this had an exhaust leak and bought this and great seal no more leak and simple install
  
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Fits Like a Charm 7 years ago
5out of 5stars
Sunman
I highly recommend this part if you are retaining OEM downpipe and to aftermarket CBE to ensure there will not be any exhaust leak. It fits like a charm. My worries were that this would push the Invidia N1's out too far (i.e., showing too much tip) on my 2016 WRX, but it was just right.
  
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1 of 1 people found the following review helpful
08 Subaru impreza wrx  7 years ago
5out of 5stars
Rickers22
Exactly what I needed. Bought the car noticed a horrible exhaust leak. Did some research and found they just slapped the invidia catback exhaust on without using this kit and tossed the donut gasket. Bough this and went to the dealership to get the donut gasket and it all bolted right up. Didn't have to remove the hangers or anything enough play to easily make it work. Install was a breeze evwn though no instrucrions came with it. Old exhaust bolts snapped when taking them off but new ones comes with the kit. If you have a stock downpipe and an aftermarket exhaust this is a must and don't forget the donut gasket.
  
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Definitely a must! 8 years ago
5out of 5stars
Jay Subie
Use this with new exhaust and work like a charm! Buy this with your exhaust!
  
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Works Great 8 years ago
5out of 5stars
jmales
Installed this about a month ago and have had no problems with it
  
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User Media for: GrimmSpeed OEM Downpipe to 3in Cat Back Adapter  - Subaru Turbo Models