[Hockeytyme]

I'm curious if anyone has gone from full DP's with an exhaust and went to running just lowers and how much of a decrease in sound they noticed.

I'm also wondering if they killed the smell as well?

[r33_RGSport]

Sound will be about 60% less.
Smell about 80-90% less.

[boredM]

Im running full remus with secondary downpipes and its bordering too loud.

I have the uppers but there is no way Im installing them, in fact Im still considering removing the secondaries.

I dont have any noticeable smell btw.

[Hockeytyme]

Originally Posted by r33_RGSport

Sound will be about 60% less.
Smell about 80-90% less.

Originally Posted by boredM

Im running full remus with secondary downpipes and its bordering too loud.

I have the uppers but there is no way Im installing them, in fact Im still considering removing the secondaries.

I dont have any noticeable smell btw.

Thanks for the input, it might be worth at least trying with just lowers before taking it both off. Like you boredM I have full Remus but I have both upper and lower and it's crazy loud. I feel like a jerk just doing a 4k rpm pass on someone.

The downside is I won't be able to push as much boost and power when I want to but heck, I can still run a map2 10.2-10.3 which isn't too shabby.

I'm guessing if you were using a tune that most tunes don't suggest a stage 2 without full DP's as opposed to just lower? I know EGT will get too high
with a stage 2 on stock DP's so I'm wondering if just lower would change that.

[r33_RGSport]

Originally Posted by Hockeytyme

Thanks for the input, it might be worth at least trying with just lowers before taking it both off. Like you boredM I have full Remus but I have both upper and lower and it's crazy loud. I feel like a jerk just doing a 4k rpm pass on someone.

The downside is I won't be able to push as much boost and power when I want to but heck, I can still run a map2 10.2-10.3 which isn't too shabby.

I'm guessing if you were using a tune that most tunes don't suggest a stage 2 without full DP's as opposed to just lower? I know EGT will get too high
with a stage 2 on stock DP's so I'm wondering if just lower would change that.

If you are still going to run Stage2 map, I suggest to keep the upper catless and keep the secondary cat to reduce the noise and smell.
Because with Stage2 mapping, you will burn or damage the stock cat since it is very dense and will burned up due to high EGT.

[yellowssm]

Originally Posted by r33_RGSport

If you are still going to run Stage2 map, I suggest to keep the upper catless and keep the secondary cat to reduce the noise and smell.
Because with Stage2 mapping, you will burn or damage the stock cat since it is very dense and will burned up due to high EGT.

How long does it take to "burn up" the factory cat if running aggressive tuning?

[r33_RGSport]

Originally Posted by yellowssm

How long does it take to "burn up" the factory cat if running aggressive tuning?

All depends.
If you drive it normally, should be quite a long time.
But, if you mashing it a lot, then you may burn it faster.

Also, don't turn off the cold-start if you are running cat.
I saw customer damaged a Hi-Flow cat because he turned off the cold start.

[Hockeytyme]

Originally Posted by r33_RGSport

If you are still going to run Stage2 map, I suggest to keep the upper catless and keep the secondary cat to reduce the noise and smell.
Because with Stage2 mapping, you will burn or damage the stock cat since it is very dense and will burned up due to high EGT.

I guess there is the option of going with a high flow upper from Keller but i'm not sure how much that will reduce noise and smell?

[r33_RGSport]

Originally Posted by Hockeytyme

I guess there is the option of going with a high flow upper from Keller but i'm not sure how much that will reduce noise and smell?

Hi-Flow Cat Upper with Catless Secondary, will be a bit louder than stock upper and catless secondary. I would say similar to catless upper and catted secondary. But, more power gain.
Smell, will be about the same.

[marcvtec]

This thread is the exact reason why I keep the stock exhaust and then just do a full downpipe, sounds perfect.

[Hockeytyme]

Originally Posted by marcvtec

This thread is the exact reason why I keep the stock exhaust and then just do a full downpipe, sounds perfect.

Yea, I thought about putting back on stock and going with your setup. But, I feel it's still going to be pretty damn loud.

I feel like my noise over stock is 20-30% exhaust and 70-80% comes from the DP's.. Tempted to put high flow uppers on. If that's not enough I can add stock exhaust. The exhaust does make the pitch change. It's like putting your exhaust in an empty tiled room that echos.. lol

[marcvtec]

My bet is try the stock exhaust with full dp.
As with my previous cars this for me was the best setup. (period)
Loud when I want it, nice and kinda normal when I don't.

[Hockeytyme]

Originally Posted by marcvtec

My bet is try the stock exhaust with full dp.
As with my previous cars this for me was the best setup. (period)
Loud when I want it, nice and kinda normal when I don't.

Yea, I'm tempted to try that as well. However, I kinda want to rid the smell as well.

It kind of sucks that I can't just pass someone while driving down a normal street without the whole city knowing..haha It's literally louder than my Novitech Ferrari. This would all be solved if these things just had headers and a super charger Love that old deep sound of my E39. Nascar sound as opposed to wanna be F1 sound

[shoei]

Originally Posted by Hockeytyme

Yea, I thought about putting back on stock and going with your setup. But, I feel it's still going to be pretty damn loud.

I feel like my noise over stock is 20-30% exhaust and 70-80% comes from the DP's.. Tempted to put high flow uppers on. If that's not enough I can add stock exhaust. The exhaust does make the pitch change. It's like putting your exhaust in an empty tiled room that echos.. lol

While I may not have any real world experience with one of these, it's still what I think of when I hear your car...

[BMWDriverX]

I'm installing a rear section GThaus SGT and going from there. I have a set of ER lowers in case I want more sound and also have the resonator that i can get rid of with an x-pipe. I don't want to touch the primaries because of the smell and fumes, it was disgusting on my M6 GC, stinks up the whole garage every time you pull in and of course cops driving behind you can smell it, i got a modified exhaust ticket right before I traded it in for the M5.

[Hockeytyme]

Originally Posted by shoei

While I may not have any real world experience with one of these, it's still what I think of when I hear your car...

hahahah

[Vic55]

I am happy with just the full remus- but then again Im not looking for heavy mods to get more power than just the piggy. Whats easy for me to cut sound is just push the exhaust button light to off and then the car is muted about 70% and I still can drive in Sport Plus and all other aggressive settings. The pops and bangs go away too. Its good for those early morning drives in the local hood.

[Hockeytyme]

Originally Posted by Vic55

I am happy with just the full remus- but then again Im not looking for heavy mods to get more power than just the piggy. Whats easy for me to cut sound is just push the exhaust button light to off and then the car is muted about 70% and I still can drive in Sport Plus and all other aggressive settings. The pops and bangs go away too. Its good for those early morning drives in the local hood.

Yea, I can get pretty much the same effect with the exhaust button. But, it doesn't do crap when I'm on the pipe

[FloridaM5]

Yeah man, ditch the downpipes. I'm a catless guy typically, but on this car, not even remotely necessary....especially if you have the remus catback. Stock comp and base exhaust aren't good enough, but remus gets you there. You'll still go fast and sound good. my 5 cents.

[Hockeytyme]

Originally Posted by FloridaM5

Yeah man, ditch the downpipes. I'm a catless guy typically, but on this car, not even remotely necessary....especially if you have the remus catback. Stock comp and base exhaust aren't good enough, but remus gets you there. You'll still go fast and sound good. my 5 cents.

I hear ya buddy. I can probably still run a 10.2 and not have to deal with the noise. I am however tempted to keep the lower and put a high flow in for the upper. But, that could be a 2k waste..lol This way I could still run stage 2 tunes or higher octane JB4 maps.

[FloridaM5]

Originally Posted by Hockeytyme

I hear ya buddy. I can probably still run a 10.2 and not have to deal with the noise. I am however tempted to keep the lower and put a high flow in for the upper. But, that could be a 2k waste..lol This way I could still run stage 2 tunes or higher octane JB4 maps.

Originally Posted by Hockeytyme

I hear ya buddy. I can probably still run a 10.2 and not have to deal with the noise. I am however tempted to keep the lower and put a high flow in for the upper. But, that could be a 2k waste..lol This way I could still run stage 2 tunes or higher octane JB4 maps.

Cool cool. I'm with you; half the fun is playing around and figuring out what works best for you. I'm running map 7 (on top of ECU flash) using an e30 blend (e85 and 93 octane) with no issues. Stock downpipes.

[gtenedio]

Originally Posted by Hockeytyme

Thanks for the input, it might be worth at least trying with just lowers before taking it both off. Like you boredM I have full Remus but I have both upper and lower and it's crazy loud. I feel like a jerk just doing a 4k rpm pass on someone.

The downside is I won't be able to push as much boost and power when I want to but heck, I can still run a map2 10.2-10.3 which isn't too shabby.

I'm guessing if you were using a tune that most tunes don't suggest a stage 2 without full DP's as opposed to just lower? I know EGT will get too high
with a stage 2 on stock DP's so I'm wondering if just lower would change that.

youre not allowed to put your cats back on until we see some 9's.

F U