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Discussion Starter #1 (Edited)
Hi Guys,

This is my first post on the forum, hope its helpful!

Thought I’d share my experiences of deciding on my exhaust and finally going through with the purchase.

The F10 M5 is way too quiet for an M car. I felt the need for an exhaust the moment I drove home from the showroom! Moving over from a Jaguar XFR with a Spires exhaust, I was used to a rumbly V8 with lots of cracks and bangs.

Decision making process:
Searching through the forum, and reading about everyone’s views on exhausts and how insulated the M5 is, I wanted something on the louder side. I was in a dilemma between the RPi GTM (resonated vs un-resonated) and Eisenmann Race, as most said that these were the two loudest options. I wanted to be 100% sure on what I’m buying as shipping to India is expensive and there is a 50% import duty on the exhaust. I’ve spent numerous sleepless nights watching videos trying to make a decision, though youtube can never replicate what the exhaust actually sounds like.

This is where member Boots & Mstmng (from M5post) came to the rescue! Both, who run GTM resonated on their cars, helped me make the decision. They were both extremely helpful and prompt in answering all my questions about their experiences with the GTM. I realized the GTM was best value for money as it’s a full system with a max power gain as compared to the axle-back Eisenmann (which was also more expensive!). I also wasn’t keen on cutting into my stock exhaust, incase I needed to throw it back on someday. Finally decide on the resonated version. As my car is a daily driver, I felt that the drone from the un-resonated might not be desirable. Country run videos posted by Boots also helped make the decision. Many thanks to them for all the help!!

Purchase experience:
Josh at RPi was awesome to deal with. He patiently answered all my questions about the GTM and how the resonated compares with the un-resonated. I’ve been in touch with him for 2 months, with 100s of mails and phone calls between us, before I finally made my decision. Eloy was also extremely prompt in helping with information and tips for the install. Thumbs up to awesome customer service.

Unpacking experience & quality:
The exhaust was extremely well packed with lots and lots of foam padding; the exhaust was in perfect condition when it reached me after a long journey from California to Mumbai! The tips were separately wrapped for further protection. The fit and finish was amazing. The only drawback I found was the gap between the tips. The gap between the two tips on the left is 5mm less than the gap between the two tips on the right (gap is very clear in the pic of the rear, attached). I’m sure this is something that RPi could have looked into; a pure lapse in quality assurance. Unfortunately this is the part you can see from the back, and the difference is noticable. Nothing much I can do about this now anyway. Apart from this, it’s perfect.

The install took approx an hour. Storing the stock exhaust is going to be an issue as its one-piece front to back!

Cold start:
Cold start is much much louder than stock though it gets quiet after 20-30secs. It sounds absolutely fantastic. Idle revving is also louder, but not as loud as I expected. My car is limited to 4k rpms on idle revving, so I get the crack only every now and then, and it’s LOUD! While idling, you can hear the exhaust from inside as well, a low mellow rumble, slightly louder than stock.

Driving experience:
The exhaust is definitely audible when you get off the line, or are moving the car around slowly. A lovely low rumble. There is a short burst of drone when the gears are shifting automatically while driving around calmly. The drone is very noticeable 1.5k rpms to 2rpms, especially while engine braking. It does feel like there is an aftermarket exhaust, but isn’t all that loud from inside, even while driving hard. You do hear some more cracks on the overrun as compared to stock. But somehow I haven’t yet heard cracks on the up-shift as some others have mentioned. You do hear it well while downshifting though. I guess the F10 is way too insulated. I haven’t yet heard it driving from outside though. I’m guessing it’s more of an audible treat to bystanders than me!

It has been 4 days since I’ve installed it, and the sound has totally changed from the first day. I expected it to be louder than it is as it’s a muffler-less system. As I have read others experiences, I hope it gets louder and deeper once its all carboned up! Driven only 50km since its been installed.
As for the performance gain, maybe it’s too early to tell the difference. Not got a chance to do a highway run with anyone to compare either. Hopefully soon!

To sum everything up:
I’m very happy with my decision of buying the Resonated RPi GTM, no regrets. In my opinion, it sounds much better than the Akrapovic and the Eisenmann (only ones I've heard). It is something different as most people here are running on the much quieter Akra. Its great for a daily driver as it’s a perfect match for an aggressive note while not being overly intrusive on a calm drive. It’s a great exhaust to have. And also, in the back of my mind I know that if I still end up finding it quiet, I can always switch to the un-resonated version, an easy swap of that section only!

Going to take some videos and post them up soon, so that you guys can share the joy of the Resonated RPi GTM along with me! I have also attached some pictures during the install process. Hope this review was useful to anyone deciding on an aftermarket exhaust!

Best,

SVJ
 

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Nice review. Post some vids!

Is it not possible to heat up the passenger side exhaust tips and push them in closer to each other?
 

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Discussion Starter #5
Nice review. Post some vids!

Is it not possible to heat up the passenger side exhaust tips and push them in closer to each other?
Waiting for the exhaust to get all carboned up before I take some videos. The sound has changed considerably since I installed it. Apart from not yet having time to take videos! But will definitely take some and put them up soon.

As for the tips, not sure if I should take a chance and tamper with the welding, maybe not worth the risk.

SVJ
 

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Discussion Starter #7
The picture is taking on the passenger side which you can see the outer tip more. Instructions for adjustment as been sent. ;)
Will be trying to adjust the exhaust again based on the instructions sent (front/back & up/down adjustment), I'm sure it will sit more flush with the bumper once adjusted. Thanks Eloy!

Though the gap between the two tips on the left and the two tips on the right cannot be changed (pic attached). Sometimes I wish that I didn't notice such small alignment issues! Luckily I barely see my car from outside while its driving (sometimes when my Dad uses it!).

SVJ

P.S will be posting videos once I've done enough KMs for breaking in the exhaust.
 

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Waiting for the exhaust to get all carboned up before I take some videos. The sound has changed considerably since I installed it. Apart from not yet having time to take videos! But will definitely take some and put them up soon.

As for the tips, not sure if I should take a chance and tamper with the welding, maybe not worth the risk.

SVJ
Hey just go take the vids. Put a mic on the lp and put the foot down. Your missing out on what the exhaust really sounds like.
 
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Will be trying to adjust the exhaust again based on the instructions sent (front/back & up/down adjustment), I'm sure it will sit more flush with the bumper once adjusted. Thanks Eloy!

Though the gap between the two tips on the left and the two tips on the right cannot be changed (pic attached). Sometimes I wish that I didn't notice such small alignment issues! Luckily I barely see my car from outside while its driving (sometimes when my Dad uses it!).

SVJ

P.S will be posting videos once I've done enough KMs for breaking in the exhaust.
Ah, don't worry about noticing those things. I would be just as anal about it. Do you have Skype or Tango? Please contact me when you can so we can resolve this issue. The gaps are not acceptable and we want to see how this happened.
 

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Ah, don't worry about noticing those things. I would be just as anal about it. Do you have Skype or Tango? Please contact me when you can so we can resolve this issue. The gaps are not acceptable and we want to see how this happened.
Will call you in a day or two, post the new year madness. Due to the time difference, I have to call you post midnight my time! I've had long chats with Josh late at night (my time) while deciding on the exhaust! my wife used to wonder what the hell I'm doing discussing exhausts at that hour! haha
 

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Will call you in a day or two, post the new year madness. Due to the time difference, I have to call you post midnight my time! I've had long chats with Josh late at night (my time) while deciding on the exhaust! my wife used to wonder what the hell I'm doing discussing exhausts at that hour! haha
Sure thing, or you can email me and Ill give you my Skype user name if you want to go that route. Too bad Josh is not a hot young girl. hahaha
 

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Ah, don't worry about noticing those things. I would be just as anal about it. Do you have Skype or Tango? Please contact me when you can so we can resolve this issue. The gaps are not acceptable and we want to see how this happened.
This is how you deal with things as a sponsored vendor on a forum. PROPS RPI.
 

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We will replace the tips. I checked all the tips we have here as well as our production jig and there were no differences in the tips so I think it must have been bent some how from shipping. Shoot me an email and we will arrange for shipping info if an exchange is what you want to do :)
 

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We will replace the tips. I checked all the tips we have here as well as our production jig and there were no differences in the tips so I think it must have been bent some how from shipping. Shoot me an email and we will arrange for shipping info if an exchange is what you want to do :)
Thank you for awesome customer service!! I will call you later today

SVJ
 

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I'm glad they are replacing the tips. Really doesn't look right. That sort of thing would drive me crazy! Call me OCD!
 
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I'm glad they are replacing the tips. Really doesn't look right. That sort of thing would drive me crazy! Call me OCD!
We are all OCD here. lol. Its a good thing given that the attention is given to our cars, guns, etc. We double checked the inventory we had here as well as our production jig. Everything is even and we think the tips may have been damaged from shipping. There are a lot of hands that have contact with that box from here in Torrance, CA all the way to India. All though we try to package our stuff as bullet proof as possible, sometimes these things happen....but rarely.

Thanks for being patient with us :)
 

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I'm glad they are replacing the tips. Really doesn't look right. That sort of thing would drive me crazy! Call me OCD!
RPi has given me some suggestions to try and fix the gap issue at my end itself. Ideal option.
Going through with the swap will be a nightmare as shipping costs all the way to California from India are exorbitant. Plus I'll have to pay import duty again on the replacement part that comes in!

SVJ
 

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At least you get those nice hot lunches for like 4 pounds a month...saw it on top gear when they went to India. Good luck with your exhaust mate.
 
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