GRP Emira Decat Pipes Now Available!

1stLotus

Active member
Joined
Jan 3, 2024
Messages
31
Reaction score
18
Location
US
I’d be curious to hear all the different exhaust setups is an exhaust shootout. I’m debating between a decat and keeping the original muffler or keeping the 3rd cat and getting a Milltek or GRP muffler that is more of a straight-through setup.

Can anyone describe the differences of the two?
 
OP
GRP

GRP

Emira Fan
Supporting Vendor
Joined
Sep 28, 2021
Messages
215
Reaction score
654
Location
Reno NV, USA
Emira Status
Emira Owner
  • Thread Starter
  • Thread starter
  • #122
I’d be curious to hear all the different exhaust setups is an exhaust shootout. I’m debating between a decat and keeping the original muffler or keeping the 3rd cat and getting a Milltek or GRP muffler that is more of a straight-through setup.

Can anyone describe the differences of the two?
I typically recommend starting with the decat pipe, driving it for a while and if you want more then look into getting the muffler at that point.
We have some video planned to show the difference between the decat and the decat + our muffler setup asap. Just waiting on the videographer.
 

1stLotus

Active member
Joined
Jan 3, 2024
Messages
31
Reaction score
18
Location
US
I typically recommend starting with the decat pipe, driving it for a while and if you want more then look into getting the muffler at that point.
We have some video planned to show the difference between the decat and the decat + our muffler setup asap. Just waiting on the videographer.
I appreciate your recommendation - it’s super helpful. Btw, I already picked up your decat 👌
 
  • Like
Reactions: GRP

ADC

Just Jazzed About Being On The Show
Joined
Nov 12, 2021
Messages
854
Reaction score
1,783
Location
Oxfordshire
Emira Status
Emira on order
I typically recommend starting with the decat pipe, driving it for a while and if you want more then look into getting the muffler at that point.
We have some video planned to show the difference between the decat and the decat + our muffler setup asap. Just waiting on the videographer.
Not to be difficult (well, actually, totally being difficult :) ), but could you pretty-please-with-sugar-on-top also try to include what just the muffler change without decat sounds like? 🥺 🙏

I'm in the camp of wanting to go with the GRP titanium system after the cat (for weight reduction and some sound increase when valve-open), but don't really fancy taking out the 3rd cat and a) possibly complicating my life with MOT test failures / tickets from Mr Plod, and b) pissing all my neighbours off. I definitely care more about sound quality than outright volume.
 
OP
GRP

GRP

Emira Fan
Supporting Vendor
Joined
Sep 28, 2021
Messages
215
Reaction score
654
Location
Reno NV, USA
Emira Status
Emira Owner
  • Thread Starter
  • Thread starter
  • #125
Not to be difficult (well, actually, totally being difficult :) ), but could you pretty-please-with-sugar-on-top also try to include what just the muffler change without decat sounds like? 🥺 🙏

I'm in the camp of wanting to go with the GRP titanium system after the cat (for weight reduction and some sound increase when valve-open), but don't really fancy taking out the 3rd cat and a) possibly complicating my life with MOT test failures / tickets from Mr Plod, and b) pissing all my neighbours off. I definitely care more about sound quality than outright volume.
We could do that, the decat is an easy swap so we will get some video of just the muffler setup installed as well.
 

K_Squared

Emira Fanatic
Joined
Mar 2, 2023
Messages
399
Reaction score
829
Location
Raleigh, NC, USA
Emira Status
Emira Owner
Are pops and burbles present? The video cuts off before they would be heard.
Lots of burbles on the overrun. Not really 'pops' though like you hear on BMWs and the like. I think it's perfect with this setup. Apart from maybe the Larini exhaust, I've yet to see any other videos/comparisons that would compel me to do anything further with the exhaust than these two small mods.

I'm waiting for @GRP to change my mind :)
 

tnbuilder

Active member
Joined
Mar 19, 2024
Messages
31
Reaction score
11
Location
TN, USA
I am thinking just the decat and valve controller too. I would like to see more videos of just the decat and controller. The very few I have seen are not great...most of the good videos are of a full exhaust.
 

K_Squared

Emira Fanatic
Joined
Mar 2, 2023
Messages
399
Reaction score
829
Location
Raleigh, NC, USA
Emira Status
Emira Owner
Got these today by a photographer while doing an Emira photo shoot. Sorry I didn't get any stationary rev vids, I'll get some of those soon and add. This is with the GRP Decat pipe + Milltek full open. That's it! Use some good headphones.



 
Last edited:
OP
GRP

GRP

Emira Fan
Supporting Vendor
Joined
Sep 28, 2021
Messages
215
Reaction score
654
Location
Reno NV, USA
Emira Status
Emira Owner
  • Thread Starter
  • Thread starter
  • #132

K_Squared

Emira Fanatic
Joined
Mar 2, 2023
Messages
399
Reaction score
829
Location
Raleigh, NC, USA
Emira Status
Emira Owner
I am surrounded by poppin' idiots in their BMWs around here, hopefully the fad passess.
My 340i with the M Perf exhaust does lots of pops in stock form. I'm not a huge fan, either. I plan to tune them out when I get around to it. They're a bit too "I'm 21 and I got a bimmer!" for me at 38 years old.
 

1stLotus

Active member
Joined
Jan 3, 2024
Messages
31
Reaction score
18
Location
US
Awesome! Would be nice to have a comparison like this back to back eventually like this: . The only difference between the two is that the R version doesn't have the 3rd cat (which comes in stock form).
 

EZcheezy

Emira Fanatic
Joined
Jul 22, 2023
Messages
309
Reaction score
367
Location
Texas
Emira Status
Emira on order
anyone know how open the valves are open in tour / sport / track?

im assuming the miltek controller puts it at 100% open?
 
OP
GRP

GRP

Emira Fan
Supporting Vendor
Joined
Sep 28, 2021
Messages
215
Reaction score
654
Location
Reno NV, USA
Emira Status
Emira Owner
  • Thread Starter
  • Thread starter
  • #137
anyone know how open the valves are open in tour / sport / track?

im assuming the miltek controller puts it at 100% open?
Based solely on observation of someone changing modes in the car while I watched the valve on the lift I noticed that sport and track open the valve roughly 30-40% at idle and then it opens gradually as the rpms increase to about 4500 where it is open 100%
The controller bypasses that and will open it 100%, 0% or have stock pass through function.
 

brainf18

Emira Fan
Joined
Jan 16, 2022
Messages
183
Reaction score
369
Location
Louisville KY ("the Ville")
Emira Status
Emira on order
I typically recommend starting with the decat pipe, driving it for a while and if you want more then look into getting the muffler at that point.
We have some video planned to show the difference between the decat and the decat + our muffler setup asap. Just waiting on the videographer.
For comparison, please use a decibel meter at a fixed distance from the exhaust and in the cabin at WOT and cruising at Highway speeds. Its sometimes hard to "hear" the difference on a video....but the decibel meter gives a good reading of increased volume and how much "drone" can be expected when just cruising from A to B.
 

Rapture

Well-known member
Joined
Mar 27, 2022
Messages
84
Reaction score
120
Location
Milwaukee, WI
Emira Status
Emira Owner
I installed the decat pipe and exhaust controller in my garage today on 8-inch Race Ramp wheel cribs (really liked those btw). It wasn't too bad, but I definitely needed that rubber mallet and a 2X2 to get the third cat to exit. Install was very straight forward, Greg provides great instructions.

These products are transformational to the sound yet provides flexibility to adjust to your preference at the moment.
 

Similar threads

Top