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GrimmSpeed OEM Downpipe to 3in Cat Back Adapter

MODEL # GRM 077046

$39.00


46 Reviews
4.8 out of 5 Stars
5 Stars
(42)
4 Stars
(3)
3 Stars
(0)
2 Stars
(0)
1 Stars
(1)
Customer Photos and Videos
GrimmSpeed OEM Downpipe to 3in Cat Back Adapter  ( Part Number: 077046)
GrimmSpeed OEM Downpipe to 3in Cat Back Adapter  ( Part Number: 077046)
Easy to Install and Fits Great 22 days ago
5out of 5stars

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  1 month ago
5out of 5stars

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! 2 months ago
5out of 5stars

A must have for anyone running a catback with the OEM downpipe! Hardware is top notch as well!
  
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Perfect  2 months ago
5out of 5stars

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 6 months ago
5out of 5stars

Great part worked great no leaks
  
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It Works 1 year ago
5out of 5stars

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.  1 year ago
5out of 5stars

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 1 year ago
5out of 5stars

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 2 years ago
5out of 5stars

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 2 years ago
5out of 5stars

Simple and simplifies installation of catback exhaust to OEM downpipe.
  
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Easy install 2 years ago
5out of 5stars

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!  2 years ago
5out of 5stars

Had the stock downpipe, needed this adapter for my Invidia q300 exhaust fit perfect!
  
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Get a Donut! 2 years ago
5out of 5stars

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 2 years ago
5out of 5stars

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!  2 years ago
5out of 5stars

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 3 years ago
5out of 5stars

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 3 years ago
5out of 5stars

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 3 years ago
5out of 5stars

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  3 years ago
5out of 5stars

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 3 years ago
5out of 5stars

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  3 years ago
5out of 5stars

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! 4 years ago
5out of 5stars

Use this with new exhaust and work like a charm! Buy this with your exhaust!
  
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Works Great 4 years ago
5out of 5stars

Installed this about a month ago and have had no problems with it
  
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Serve their purpose 4 years ago
5out of 5stars

Nothing too spectacular to write here, the adapter worked perfectly to mate my Invidia N1 dual catback to my stock downpipe. No leaks whatsoever!
  
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does what it needs to 4 years ago
5out of 5stars

Used with the invidia n1 catback. Make sure you put it on correctly..can be a little confusing !
  
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Perfect 4 years ago
5out of 5stars

Used to connect an Invidia Q300 exhaust system on a '15 STi. Fitment was great. Definitely recommend.
  
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Perfect adapter! 4 years ago
5out of 5stars

Used to connect 3 Invidia catback exhaust on 2009 WRX. Worked perfectly. Should be offered as a necessary(or at least highly recommended) accessory for installing a catback exhaust on 2009 WRXs.
  
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Works perfectly 4 years ago
5out of 5stars

Had this product with the stock dp with a Tomei Ti catback and worked flawless. Would recommend to anyone with a stock dp
  
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Easy install 4 years ago
5out of 5stars

I used this adaptor together with the invidia q300 (WRX STI MY15). No leaks!
  
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Easy install, great functionality 4 years ago
5out of 5stars

Perfect install, served the purpose with no leaks, until I got a 3 downpipe.
  
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GrimmSpeed OEM Downpipe to 3in Cat Back Adapter  (Part Number: )
GrimmSpeed OEM Downpipe to 3in Cat Back Adapter  (Part Number: )