Another Exhaust Question

BMPOWERED · 09-21-2017, 09:22 PM

So I've searched and found quite a few threads that almost address what I am trying to do. I am content with the sound of my 650I GC but would like to upgrade to the M6 style diffuser and quad 3.5" tips. The closest I have found to this set up here is by member "skillz..." He was able to cut off the trapezoid tips and install 3" quad tips all while maintaining the exhaust valve that controls the flap. He stated that he thought 3.5" tips would not work with the stock exhaust because the openings were too close. Another member, "sixpost" I believe was able to use a type of S pipe in order to get 4" tips to work with the stock exhaust. However he had to cut off the entire valve assembly, which I prefer not to do. Has anyone here successfully upgraded to 3.5" quad tips while leaving the valve in place? Thanks in advance.

MSUGOGRN · 09-24-2017, 05:49 PM

Sixpost is the only person who has been successful in retaining the stock mufflers but obtaining at least 3.5" tips. You are definitely right that skillz's solution will only get you 3" at the most. I am still trying to figure out exactly how sixpost achieved that with the S pipe as I really would like to switch to 4" tips and maintain my stock exhaust. I was not aware that the valves needed to be cut off though.

If sixpost's solution does not work, you are either looking at having to purchase new axle-back exhaust such as Megan Racing which will give you a 3.5" look or doing a muffler delete like I have done. However, I would highly recommend against it as the drone is terrible.

SixPost · 09-24-2017, 07:22 PM

I'm getting credit I don't deserve here... I swapped a stock M6 diffuser and carbon fiber center piece, along with stock M6 mufflers and tips onto my 650. I removed the stock tips from the mufflers and had them powdercoated silk black, halfway between matte and gloss. The resulting look isn't stock, but it doesn't look too modded either. There is exactly .75 inch between the stock M6 tips in stock position.... You should be able to crunch the numbers from there to see if your 3.5 inch tips will work. There are lots of aftermarket options for M5 / M6 tips and every seller has pics of the tips in place so you can preview the look. I was worried about the M6 setup being too loud, as I liked the stock sound too. I was pleasantly surprised that the M6 setup really isn't too much louder, just different. The M6 mufflers have the same valve system and ground points as the stock ones. I would do it again in a second. If you're determined to stay with the stock mufflers, none of this will help you. There's a lot of unknowns there and once you cut the trapezoids off, you're committed to doing something else. Good luck either way...

BMPOWERED · 09-25-2017, 03:16 AM

Thank you both. I've been searching too many threads and can't figure out for the life of me which member did the S-pipe mod. I may end up just doing like you did Sixpost and finding some M6 mufflers, but changing to 3.5" quads since I know they will work. Per your numbers, quad 3.5" tips should leave about .25" between the tips. Msugogrn, I've been following your threads as well. Good luck in getting your desired results. Car looks great by the way.

MSUGOGRN · 09-25-2017, 11:17 AM

Quote:

Originally Posted by SixPost

I'm getting credit I don't deserve here... I swapped a stock M6 diffuser and carbon fiber center piece, along with stock M6 mufflers and tips onto my 650. I removed the stock tips from the mufflers and had them powdercoated silk black, halfway between matte and gloss. The resulting look isn't stock, but it doesn't look too modded either. There is exactly .75 inch between the stock M6 tips in stock position.... You should be able to crunch the numbers from there to see if your 3.5 inch tips will work. There are lots of aftermarket options for M5 / M6 tips and every seller has pics of the tips in place so you can preview the look. I was worried about the M6 setup being too loud, as I liked the stock sound too. I was pleasantly surprised that the M6 setup really isn't too much louder, just different. The M6 mufflers have the same valve system and ground points as the stock ones. I would do it again in a second. If you're determined to stay with the stock mufflers, none of this will help you. There's a lot of unknowns there and once you cut the trapezoids off, you're committed to doing something else. Good luck either way...

First, I see your license plate and given my screen name, I will through a quick Go Green out there.

Now, I think I was mistaken when discussing who has done what with their exhaust. Sixpost swapped out his mufflers for the m6 ones. Only problem for me (not the OP) is that 4" tips won't fit the m6 outlets (per quote above only 0.75" of space after 3.5" tips are installed). For the OP though, the m6 mufflers are probably the best option as there a ton of 3.5" tips. I think Cyba makes some really great looking tips that are a simple slip on and achieve the 3.5" look.

The poster with the s pipe is araithat. And that is discussed in the thread below. Still waiting to see pics one day!

http://www.6post.com/forums/showthread.php?t=1367229&page=2

Thanks for the compliments BMWShay. Let's see pics when you get it done!

araithat · 09-25-2017, 11:28 AM

hey guys, sorry i've been a bit MIA and haven't gotten around to the pics. I tried once but I could't zoom out enough to take the picture without hoisting the car up.

To achieve the look, I HAD to cut off the valve system to get the space required. It looks perfect IMO (car pics are in the other thread). I'll try to take a picture again today.

I had to cut off the valve system but can easily weld it back on if I ever want to reverse the modification.

In terms of noise...

It basically would sound very similar to cars that have their valve control wired open. It sounds a bit more aggressive. I get a pop sometimes when coming down to a full stop. The loudness of the pop varies. Between 2000 - 2500 RPM or so, I do get some humming from the exhaust but it is barely noticeable (although this can be subjective) especially if you have any music on.

I initially was going to go the M6 muffler route but I was hearing too many stories of excessive drone.

I am still considering switching to the Eisenmenn Sport but I haven't been able to gather much info on drone with this system. If anyone has an experience with the exhaust, please chime in...

All in all, I went with the exhaust set up that I believe would give me the least drone. Pics coming, i'll go try to take them during lunch.

MSUGOGRN · 09-25-2017, 12:58 PM

Thanks araithat! You definitely took a unique approach to your exhaust. I didn't realize you had to cut off the valves but that makes total sense as you had to make room for the s pipe. The fact that you have some drone is a little concerning but I have to believe that the drone from my muffler delete is night and day louder. Also, I think you had mentioned that the tips were supplied by the exhaust shop. Any idea what type they were? Looking forward to the pics.

araithat · 09-25-2017, 01:36 PM

had to hang over a speed bump to take this picture lol...

There is a little drone. If you have a muffler delete it currently, i'm pretty sure this method will sound 1000 times quieter. You may not even notice it. Depending on what bumper you are using you may be able to do a custom s pipe after the exhaust valve.

I also cut off the exhaust valve also because it was rubbing against the aftermarket rear bumper/diffuser i had installed.

The second pic shows the shape of the exhaust tip I used. I cut the tips off, powder coated them gloss black, and put those on the s pipe and straight pipe extensions. They are 4" tips. If you really are interested on more info on where I got the tips and had it done send me a pm.

Hope this helps...

MSUGOGRN · 09-25-2017, 05:04 PM

Really good stuff. I can easily see everything you did now. Thanks!

BMPOWERED · 09-26-2017, 01:09 AM

Thanks for the response and the pics Araithat. Now the whole S pipe thing makes sense. Part of me is tempted to go your route and cut the valves. I keep my exhaust flaps zip tied open anyway and the sound is perfect for me. However, the idea of just cutting off a component of the car is killing me. Or I can go the Sixpost route and get M6 mufflers. And to confirm MSUGOGRN, I can get M6 mufflers and just add slip-on 3.5" tips while keeping the valves??? The other option is the Skilz4u2nv route and cut the trapezoids behind the valves and weld on some 3" tips. The exhaust shops I've been to even seem perplexed and not willing or able to do what Skilz did even after showing them some screenshots of his pics. Skilz are you out there to chime in?

SixPost · 09-26-2017, 05:49 AM

Lots of slip on tip options for M6 mufflers. M6 mufflers have the very same valve system your stock mufflers do... Zero drone with the M6 mufflers in my experience (valves functioning)... none of my research suggested that M6 mufflers would drone... not sure where that idea came from.

BMPOWERED · 09-28-2017, 12:06 AM

Quote:

Originally Posted by SixPost

Lots of slip on tip options for M6 mufflers. M6 mufflers have the very same valve system your stock mufflers do... Zero drone with the M6 mufflers in my experience (valves functioning)... none of my research suggested that M6 mufflers would drone... not sure where that idea came from.

I have decided (for now at least) to go this route. I think some people classify drone differently. For example, I have my valves/flaps open via the ziptie method. I do notice what one may consider slight drone upon acceleration from low rpms. However, when at any cruising speed, it as quiet as can be. The cruising speed drone is the type that I would consider annoying. Now, on to the classifieds to find some M6 mufflers...

DerBosewicht · 01-28-2018, 02:42 PM

Quote:

Originally Posted by SixPost

I'm getting credit I don't deserve here... I swapped a stock M6 diffuser and carbon fiber center piece, along with stock M6 mufflers and tips onto my 650.

As long as you have the M-Sport bumper is the diffuser direct fit? And mufflers direct bolt on?

Duff Ace · 01-28-2018, 04:35 PM

Quote:

Originally Posted by MSport650Eye

As long as you have the M-Sport bumper is the diffuser direct fit? And mufflers direct bolt on?

Yes and yes

MSUGOGRN · 01-29-2018, 12:35 PM

I'll be having my M6 mufflers installed this week. So excited to finally be done with this muffler delete!

BMPOWERED · 02-01-2018, 09:54 PM

Quote:

Originally Posted by MSUGOGRN

I'll be having my M6 mufflers installed this week. So excited to finally be done with this muffler delete!

I think you'll be pleased. If you want, PM me your number and I'll send you a couple of vid clips.

MSUGOGRN · 02-05-2018, 06:32 PM

Quote:

Originally Posted by BMWShay

I think you'll be pleased. If you want, PM me your number and I'll send you a couple of vid clips.

Just added pics. Really happy so far!

http://www.6post.com/forums/showpost...07&postcount=8

BMPOWERED · 02-08-2018, 06:37 PM

Looks awesome! My muffler guy told me something similar about the M6 mufflers not fitting perfectly due to hanger location but it was an easy fix. I figured I got an F12 or F13 set that was slightly different than my F06 GC. Glad it finally worked out for you!

09-21-2017, 09:22 PM	#1
BMPOWERED Second Lieutenant 65 Rep 239 Posts Drives: 2014 650 GC M sport Join Date: Dec 2013 Location: So Cal iTrader: (0)	Another Exhaust Question - 3.5" Quad Tips on 650i So I've searched and found quite a few threads that almost address what I am trying to do. I am content with the sound of my 650I GC but would like to upgrade to the M6 style diffuser and quad 3.5" tips. The closest I have found to this set up here is by member "skillz..." He was able to cut off the trapezoid tips and install 3" quad tips all while maintaining the exhaust valve that controls the flap. He stated that he thought 3.5" tips would not work with the stock exhaust because the openings were too close. Another member, "sixpost" I believe was able to use a type of S pipe in order to get 4" tips to work with the stock exhaust. However he had to cut off the entire valve assembly, which I prefer not to do. Has anyone here successfully upgraded to 3.5" quad tips while leaving the valve in place? Thanks in advance. __________________ 2014 BMW 650GC M sport 2011 BMW 550i M-sport/AW 1991 Nissan 300ZX Twin Turbo 2007 Chevrolet Corvette Z51 (sold) 2001 BMW 325ci (sold)
	Appreciate 0 Tweet Quote

09-24-2017, 05:49 PM	#2
MSUGOGRN Second Lieutenant 66 Rep 264 Posts Drives: 2021 Black X3MC Join Date: Jan 2017 Location: Denver, CO iTrader: (1)	Sixpost is the only person who has been successful in retaining the stock mufflers but obtaining at least 3.5" tips. You are definitely right that skillz's solution will only get you 3" at the most. I am still trying to figure out exactly how sixpost achieved that with the S pipe as I really would like to switch to 4" tips and maintain my stock exhaust. I was not aware that the valves needed to be cut off though. If sixpost's solution does not work, you are either looking at having to purchase new axle-back exhaust such as Megan Racing which will give you a 3.5" look or doing a muffler delete like I have done. However, I would highly recommend against it as the drone is terrible.
	Appreciate 0 Quote

09-24-2017, 07:22 PM	#3
SixPost Private 18 Rep 67 Posts Drives: 2015 650i Xdrive Alpine White Join Date: Sep 2016 Location: Parts Unknown iTrader: (0)	Quads I'm getting credit I don't deserve here... I swapped a stock M6 diffuser and carbon fiber center piece, along with stock M6 mufflers and tips onto my 650. I removed the stock tips from the mufflers and had them powdercoated silk black, halfway between matte and gloss. The resulting look isn't stock, but it doesn't look too modded either. There is exactly .75 inch between the stock M6 tips in stock position.... You should be able to crunch the numbers from there to see if your 3.5 inch tips will work. There are lots of aftermarket options for M5 / M6 tips and every seller has pics of the tips in place so you can preview the look. I was worried about the M6 setup being too loud, as I liked the stock sound too. I was pleasantly surprised that the M6 setup really isn't too much louder, just different. The M6 mufflers have the same valve system and ground points as the stock ones. I would do it again in a second. If you're determined to stay with the stock mufflers, none of this will help you. There's a lot of unknowns there and once you cut the trapezoids off, you're committed to doing something else. Good luck either way... Attached Images
	Appreciate 3 P111569.00 gmusquiz6.00 Mr.Brightside39.50 Quote

09-25-2017, 03:16 AM	#4
BMPOWERED Second Lieutenant 65 Rep 239 Posts Drives: 2014 650 GC M sport Join Date: Dec 2013 Location: So Cal iTrader: (0)	Thank you both. I've been searching too many threads and can't figure out for the life of me which member did the S-pipe mod. I may end up just doing like you did Sixpost and finding some M6 mufflers, but changing to 3.5" quads since I know they will work. Per your numbers, quad 3.5" tips should leave about .25" between the tips. Msugogrn, I've been following your threads as well. Good luck in getting your desired results. Car looks great by the way. __________________ 2014 BMW 650GC M sport 2011 BMW 550i M-sport/AW 1991 Nissan 300ZX Twin Turbo 2007 Chevrolet Corvette Z51 (sold) 2001 BMW 325ci (sold)
	Appreciate 0 Quote

09-25-2017, 11:28 AM	#6
araithat Enlisted Member 9 Rep 34 Posts Drives: 650i gran coupe m sport Join Date: Mar 2017 Location: Toronto iTrader: (0)	hey guys, sorry i've been a bit MIA and haven't gotten around to the pics. I tried once but I could't zoom out enough to take the picture without hoisting the car up. To achieve the look, I HAD to cut off the valve system to get the space required. It looks perfect IMO (car pics are in the other thread). I'll try to take a picture again today. I had to cut off the valve system but can easily weld it back on if I ever want to reverse the modification. In terms of noise... It basically would sound very similar to cars that have their valve control wired open. It sounds a bit more aggressive. I get a pop sometimes when coming down to a full stop. The loudness of the pop varies. Between 2000 - 2500 RPM or so, I do get some humming from the exhaust but it is barely noticeable (although this can be subjective) especially if you have any music on. I initially was going to go the M6 muffler route but I was hearing too many stories of excessive drone. I am still considering switching to the Eisenmenn Sport but I haven't been able to gather much info on drone with this system. If anyone has an experience with the exhaust, please chime in... All in all, I went with the exhaust set up that I believe would give me the least drone. Pics coming, i'll go try to take them during lunch.
	Appreciate 0 Quote

09-25-2017, 12:58 PM	#7
MSUGOGRN Second Lieutenant 66 Rep 264 Posts Drives: 2021 Black X3MC Join Date: Jan 2017 Location: Denver, CO iTrader: (1)	Thanks araithat! You definitely took a unique approach to your exhaust. I didn't realize you had to cut off the valves but that makes total sense as you had to make room for the s pipe. The fact that you have some drone is a little concerning but I have to believe that the drone from my muffler delete is night and day louder. Also, I think you had mentioned that the tips were supplied by the exhaust shop. Any idea what type they were? Looking forward to the pics.
	Appreciate 0 Quote

09-25-2017, 01:36 PM	#8
araithat Enlisted Member 9 Rep 34 Posts Drives: 650i gran coupe m sport Join Date: Mar 2017 Location: Toronto iTrader: (0)	had to hang over a speed bump to take this picture lol... There is a little drone. If you have a muffler delete it currently, i'm pretty sure this method will sound 1000 times quieter. You may not even notice it. Depending on what bumper you are using you may be able to do a custom s pipe after the exhaust valve. I also cut off the exhaust valve also because it was rubbing against the aftermarket rear bumper/diffuser i had installed. The second pic shows the shape of the exhaust tip I used. I cut the tips off, powder coated them gloss black, and put those on the s pipe and straight pipe extensions. They are 4" tips. If you really are interested on more info on where I got the tips and had it done send me a pm. Hope this helps... Attached Images
	Appreciate 0 Quote

09-25-2017, 05:04 PM	#9
MSUGOGRN Second Lieutenant 66 Rep 264 Posts Drives: 2021 Black X3MC Join Date: Jan 2017 Location: Denver, CO iTrader: (1)	Really good stuff. I can easily see everything you did now. Thanks!
	Appreciate 0 Quote

09-26-2017, 01:09 AM	#10
BMPOWERED Second Lieutenant 65 Rep 239 Posts Drives: 2014 650 GC M sport Join Date: Dec 2013 Location: So Cal iTrader: (0)	Thanks for the response and the pics Araithat. Now the whole S pipe thing makes sense. Part of me is tempted to go your route and cut the valves. I keep my exhaust flaps zip tied open anyway and the sound is perfect for me. However, the idea of just cutting off a component of the car is killing me. Or I can go the Sixpost route and get M6 mufflers. And to confirm MSUGOGRN, I can get M6 mufflers and just add slip-on 3.5" tips while keeping the valves??? The other option is the Skilz4u2nv route and cut the trapezoids behind the valves and weld on some 3" tips. The exhaust shops I've been to even seem perplexed and not willing or able to do what Skilz did even after showing them some screenshots of his pics. Skilz are you out there to chime in? __________________ 2014 BMW 650GC M sport 2011 BMW 550i M-sport/AW 1991 Nissan 300ZX Twin Turbo 2007 Chevrolet Corvette Z51 (sold) 2001 BMW 325ci (sold)
	Appreciate 0 Quote

09-26-2017, 05:49 AM	#11
SixPost Private 18 Rep 67 Posts Drives: 2015 650i Xdrive Alpine White Join Date: Sep 2016 Location: Parts Unknown iTrader: (0)	Quads Lots of slip on tip options for M6 mufflers. M6 mufflers have the very same valve system your stock mufflers do... Zero drone with the M6 mufflers in my experience (valves functioning)... none of my research suggested that M6 mufflers would drone... not sure where that idea came from.
	Appreciate 0 Quote

01-29-2018, 12:35 PM	#15
MSUGOGRN Second Lieutenant 66 Rep 264 Posts Drives: 2021 Black X3MC Join Date: Jan 2017 Location: Denver, CO iTrader: (1)	I'll be having my M6 mufflers installed this week. So excited to finally be done with this muffler delete!
	Appreciate 0 Quote

02-08-2018, 06:37 PM	#18
BMPOWERED Second Lieutenant 65 Rep 239 Posts Drives: 2014 650 GC M sport Join Date: Dec 2013 Location: So Cal iTrader: (0)	Looks awesome! My muffler guy told me something similar about the M6 mufflers not fitting perfectly due to hanger location but it was an easy fix. I figured I got an F12 or F13 set that was slightly different than my F06 GC. Glad it finally worked out for you! __________________ 2014 BMW 650GC M sport 2011 BMW 550i M-sport/AW 1991 Nissan 300ZX Twin Turbo 2007 Chevrolet Corvette Z51 (sold) 2001 BMW 325ci (sold)
	Appreciate 1 MSUGOGRN65.50 Quote