Review of RPi GT Exhaust

[GhostyM]

You heard the vid I posted though right??

It was like a ringing noise..

then again it could have been at cold start up and he was revving it.

[jimmyeatsworld]

Originally Posted by Chipped B6

You heard the vid I posted though right??

It was like a ringing noise..

then again it could have been at cold start up and he was revving it.

Yes I did notice that on the vid. When I'm outside on cold start, it's just damn loud with my guts vibrating... but I do not hear that noise.

You might want to ask Eloy at RPI.

[schadenfreude]

Originally Posted by Chipped B6

This is what im talking about....

hear the tinnyness in the back?

Sounds almost like something is loose and rattling around. You can hear it in gogoevo's vid, too.

[Eugene-TAIWAN]

I have read it through the 15 pages. I just have 2 questions

1. does the CEL come on?? at all??

2. If it does come on or had, how many cases of the CEL coming on??

[GhostyM]

Originally Posted by jimmyeatsworld

Yes I did notice that on the vid. When I'm outside on cold start, it's just damn loud with my guts vibrating... but I do not hear that noise.

You might want to ask Eloy at RPI.

I'm just about to message him... I really really hope that's just a cold startup.

Originally Posted by schadenfreude

Sounds almost like something is loose and rattling around. You can hear it in gogoevo's vid, too.

I really think something is just touching something makeing it ring like that.

[schadenfreude]

Originally Posted by Chipped B6

I really think something is just touching something makeing it ring like that.

My thoughts exactly.

[NFDoms2k1]

Hey all, I've had the full RPI GT on for about 1000 miles, half of which I had the corresponding RPi ECU tune by Powerchip. Here are my thoughts and some answers to your questions (done very quickly so I apologize for any errors):

I ordered the exhaust in late April while RPi was still running a free delivery special. Thinking that since it was going to be free, it was going to be slow, I was very wrong. It only took like 3 business days, so the first impression I got was very solid. Opening the box, the construction of the piece was of very high quality. Very clean welds, great lines (its almost a shame this thing is hidden under the car!) good material and very lightweight. I had to wait a few days before I could get to a lift, for I needed all the help I could get as it was going to be a DIY and I am not the best with a wrench (I figured though bolt-ons are suppose to be easy). And relatively easy it was, but even with the lift it did take me about 3.5 hours with a little help (help is definitely needed to bring down the muffler section and even the front pipes, both are heavy!). If I had to do the switch again after doing it once, it probably wouldn’t take me more than 45 minutes to do the front/mid pipes and another half hour to do the full exhaust.

When I first fired it up I was a little concerned, for I was hearing that metallic gurgling sound that I had heard about on this thread, although I hadn't noticed it in any of the videos. The first day it was very bad, there was a lot of drone, and I was having a lot of problems with what almost felt like turbo lag - and I could actually hear it too, as it almost sounded as if nothing was coming out of the exhaust at those times. I didn’t know whether I had somehow screwed up the install or what, especially since the OP had such great results immediately. I checked it again and everything seemed right, so I could only attribute it to the exhaust being brand new for one, and on top of that the computer was probably confused as hell with the second O2 sensor’s readings. And just to answer the question and not jump ahead, my CEL light never went on for the 500 miles I was going tuneless.

Every time I drove it sounded better, the drone reduced, and the "lag" feeling became less frequent and less severe, but it did take about 200 miles before I actually noticed better throttle response and power increase on the butt dyno. I still wasn't thrilled about it though, and expressed my concerns to Eloy (a great engineer and solid dude by the way). In fact I probably took out some frustration I had with the exhaust on him unfairly, but even so he would always get back to me right away. He told me the S65 engine was very raspy by nature, and the since the GT Race was so free flowing it just carried the engine’s sound through more purely. For the rasp he recommended DEI wraps and new gaskets.

The big change came when I finally got it tuned. It really made a huge difference immediately. No issues with any lag or momentary power losses, the drone which was only occurring under load from 1500-2000 RPM was greatly reduced and now extremely tolerable (girls would finally ride in the car again without negative comment) and the full power increase was finally felt, and the extra hp came extremely smoothly. I also noticed the volume of the exhaust inside the car had greatly decreased (it wasn't giving me a headache anymore when I drove with the top down) while at the same time for those on the outside of the car, particularly behind me, it got even louder. Extremely loud but not in an obnoxious way, was how more than one person described it. In fact I've been at two rallys now where people have stopped their showing off to just get in behind me to listen for a few minutes. I can't tell you how many times people have then come up to me to compliment my sound and ask me what kind of exhaust I was running. And it hasn’t just been other M3s owners - I had the privilege of being the least exotic car at an exotics car show (I was involved in the charity which was benefiting so they made an exemption). There were 6 LP640s, 6 F430s, 3 Superleggaras and 3 regular Gallardos, a GCT, that crazy SSC Ultimate Aero TT, McClaren SLR, you name it. Anyway at one point I had a Murcielago pull behind me for a bit, and then when we stopped the driver found me and gave me props (granted his DD was an M5, so he was probably the only Italian car owner who had an appreciation and interest for an M exhaust).

So with the first thousand under my belt I must say that I am very happy with my exhaust. I will admit its not perfect, as at least for me the rasp is not to my taste, but many of the other GT Race owners will tell you that it suits them just fine. As such I know Eloy and team are developing some new front pipes with small, low restriction resonators on them and I will likely be getting those as soon as they are available. If anyone has any further or more specific questions, there are a whole host of us that can answer them for you, so don’t hesitate to PM me.

[King Tut]

Got a call from Eloy today. He is shipping out my missing X pipe pronto. Hope to install the exhaust next weekend.

[Eugene-TAIWAN]

Originally Posted by NFDoms2k1

Hey all, I've had the full RPI GT on for about 1000 miles, half of which I had the corresponding RPi ECU tune by Powerchip. Here are my thoughts and some answers to your questions (done very quickly so I apologize for any errors):

I ordered the exhaust in late April while RPi was still running a free delivery special. Thinking that since it was going to be free, it was going to be slow, I was very wrong. It only took like 3 business days, so the first impression I got was very solid. Opening the box, the construction of the piece was of very high quality. Very clean welds, great lines (its almost a shame this thing is hidden under the car!) good material and very lightweight. I had to wait a few days before I could get to a lift, for I needed all the help I could get as it was going to be a DIY and I am not the best with a wrench (I figured though bolt-ons are suppose to be easy). And relatively easy it was, but even with the lift it did take me about 3.5 hours with a little help (help is definitely needed to bring down the muffler section and even the front pipes, both are heavy!). If I had to do the switch again after doing it once, it probably wouldn’t take me more than 45 minutes to do the front/mid pipes and another half hour to do the full exhaust.

When I first fired it up I was a little concerned, for I was hearing that metallic gurgling sound that I had heard about on this thread, although I hadn't noticed it in any of the videos. The first day it was very bad, there was a lot of drone, and I was having a lot of problems with what almost felt like turbo lag - and I could actually hear it too, as it almost sounded as if nothing was coming out of the exhaust at those times. I didn’t know whether I had somehow screwed up the install or what, especially since the OP had such great results immediately. I checked it again and everything seemed right, so I could only attribute it to the exhaust being brand new for one, and on top of that the computer was probably confused as hell with the second O2 sensor’s readings. And just to answer the question and not jump ahead, my CEL light never went on for the 500 miles I was going tuneless.

Every time I drove it sounded better, the drone reduced, and the "lag" feeling became less frequent and less severe, but it did take about 200 miles before I actually noticed better throttle response and power increase on the butt dyno. I still wasn't thrilled about it though, and expressed my concerns to Eloy (a great engineer and solid dude by the way). In fact I probably took out some frustration I had with the exhaust on him unfairly, but even so he would always get back to me right away. He told me the S65 engine was very raspy by nature, and the since the GT Race was so free flowing it just carried the engine’s sound through more purely. For the rasp he recommended DEI wraps and new gaskets.

The big change came when I finally got it tuned. It really made a huge difference immediately. No issues with any lag or momentary power losses, the drone which was only occurring under load from 1500-2000 RPM was greatly reduced and now extremely tolerable (girls would finally ride in the car again without negative comment) and the full power increase was finally felt, and the extra hp came extremely smoothly. I also noticed the volume of the exhaust inside the car had greatly decreased (it wasn't giving me a headache anymore when I drove with the top down) while at the same time for those on the outside of the car, particularly behind me, it got even louder. Extremely loud but not in an obnoxious way, was how more than one person described it. In fact I've been at two rallys now where people have stopped their showing off to just get in behind me to listen for a few minutes. I can't tell you how many times people have then come up to me to compliment my sound and ask me what kind of exhaust I was running. And it hasn’t just been other M3s owners - I had the privilege of being the least exotic car at an exotics car show (I was involved in the charity which was benefiting so they made an exemption). There were 6 LP640s, 6 F430s, 3 Superleggaras and 3 regular Gallardos, a GCT, that crazy SSC Ultimate Aero TT, McClaren SLR, you name it. Anyway at one point I had a Murcielago pull behind me for a bit, and then when we stopped the driver found me and gave me props (granted his DD was an M5, so he was probably the only Italian car owner who had an appreciation and interest for an M exhaust).

So with the first thousand under my belt I must say that I am very happy with my exhaust. I will admit its not perfect, as at least for me the rasp is not to my taste, but many of the other GT Race owners will tell you that it suits them just fine. As such I know Eloy and team are developing some new front pipes with small, low restriction resonators on them and I will likely be getting those as soon as they are available. If anyone has any further or more specific questions, there are a whole host of us that can answer them for you, so don’t hesitate to PM me.

So basically before its tuned the sounds not as good. Is the drone sound very loud??

Please update if you do get any CEL coming on. Did you use a RPI tune?? or another brand??

[dlbrooks18]

I heard this exhaust and saw it dyno'd in person at RPI's shop and it sounded freakin AMAZING, and with legit power gains on a dyno dynamics!! Great job RPI!!

[GhostyM]

What are they meaning with the DEI (?) wrap and gaskets to get the raspiness down?

[King Tut]

Yeah I don't know how wrap on the outside of the pipe or new gaskets will fix rasp. If new gaskets are needed they should have been included.

[GhostyM]

Originally Posted by King Tut

Yeah I don't know how wrap on the outside of the pipe or new gaskets will fix rasp. If new gaskets are needed they should have been included.

We need the vendor or Eloy to get on here and laid all this to rest.

I really want an exhaust but the way it's looking I might go Gintani.

[GhostyM]

Gosh.. even more ringing..

In that video too.. its hard to hear but there is ringing as well.



This is a disappointment.

[King Tut]

Am I the only one who doesn't buy an exhaust based on sound? I buy for horsepower and then price.

[NFDoms2k1]

Originally Posted by Eugene-TAIWAN

So basically before its tuned the sounds not as good. Is the drone sound very loud??

Please update if you do get any CEL coming on. Did you use a RPI tune?? or another brand??

Originally Posted by King Tut

Yeah I don't know how wrap on the outside of the pipe or new gaskets will fix rasp. If new gaskets are needed they should have been included.

As you see from the thread some people have a lot of rasp right off the bat, while others who get the system don't. New gaskets aren't necessary, which is why they are not included in the kit - its left up to your discretion if you need them or not (and they are not expensive and available at most BMW service centers). DEI wraps aren't necessary either, its up to your discretion as well, and they help keep heat in the exhaust and buffer the vibrational noise going through the front pipes.

[NFDoms2k1]

DEI Wraps:
http://www.dudiakracingproducts.com/...5889_5890_5892

There is also some silicone spray on the same website which helps as well.

[Eugene-TAIWAN]

Originally Posted by NFDoms2k1

As you see from the thread some people have a lot of rasp right off the bat, while others who get the system don't. New gaskets aren't necessary, which is why they are not included in the kit - its left up to your discretion if you need them or not (and they are not expensive and available at most BMW service centers). DEI wraps aren't necessary either, its up to your discretion as well, and they help keep heat in the exhaust and buffer the vibrational noise going through the front pipes.

Thanks!! I'll make sure to look into the gaskets.

[MrHarris]

Originally Posted by King Tut

Am I the only one who doesn't buy an exhaust based on sound? I buy for horsepower and then price.

You're not alone!

[jimmyeatsworld]

Originally Posted by King Tut

Am I the only one who doesn't buy an exhaust based on sound? I buy for horsepower and then price.

Ditto, I think RPI sounds good too.

[kei1225]

With just the axle back, is it more quiet than the full exhaust?
If so, is it louder than the eisenmann race?

[MrHarris]

Originally Posted by kei1225

With just the axle back, is it more quiet than the full exhaust?
If so, is it louder than the eisenmann race?

An axle back alone will be quieter than the same axle back w/ xpipe.