'14 m235 RWD vs. '16 m235 xDrive - peculiar exhaust difference/issue? |
Post Reply |
|
Thread Tools | Search this Thread |
05-17-2022, 11:30 PM | #1 |
Private
17
Rep 98
Posts |
'14 m235 RWD vs. '16 m235 xDrive - peculiar exhaust difference/issue?
I had a '14 m235 RWD 8AT with the following mods
MPE ER Catless DP JB4 I now have a '16 m235 xDrive 8AT with the following mods MPE ER Catless DP ER Charge Pipe Bootmod3 Stage 2 93 Octane When I had my '14 m235, my cold starts were very loud, loud to the point that the neighbors didn't care for it and it felt like the exhaust just breathed as free as could be. I just installed the ER catless DP on my '16 m235 and this morning when I woke up and started my car there was no difference in the exhaust sound from when I started it the prior day before the catless DP was installed. Additionally, it also does not feel like the exhaust is breathing(as I call it) as freely as my '14 m235 when I had it. I called my shop who installed it to confirm that they were sent the correct DP and it was in fact a catless version which they confirmed 100% it was. I asked them if they had any idea why this may be considering it's the same engine with the same mods besides the tune, and they were stumped. He said he could make a wild guess and a shot in the dark that maybe a piece of the old cat broke off and is lodged somewhere in the exhaust or maybe BMW changed how the car heats up when started between the '14 and '16. I also asked them if the difference in tunes would have any effect and they said no, I also asked the person from the forums who I bought my '14 from who has good knowledge of these cars and he also said the tune should have absolutely nothing to do with that. I went into my bootmod3 tune config and put the burble settings to OEM and put the cold start start settings to OEM thinking it may have something to do with that, but nothing changed. Hopefully this made even the smallest bit of sense and somebody out there can advise me or help me figure out why the same car (except the year, rwd/8AT & tune) with the same mods has a completely difference sound when first starting and a difference in the feel. Thanks in advance for any comments, suggestions, etc! |
05-18-2022, 12:18 AM | #2 |
Joint Chiefs of Staff
26111
Rep 194,536
Posts |
Not sure what is going on, it's impossible to change from the stock downpipe to catless and not have any difference in sound.
__________________
Check out our current sale by clicking on this link!
https://x-ph.com/sale/ Phone number 702-494-9435 |
Appreciate
0
|
05-18-2022, 01:41 AM | #3 | |
Private
17
Rep 98
Posts |
Quote:
|
|
Appreciate
0
|
05-18-2022, 07:10 AM | #4 |
Captain
178
Rep 643
Posts |
what's exhaust smell like? it's very significantly different between catted and not catted.
also, by default, bm3 stage 2 tunes disable cold start, so it's much quieter. if you want cold start, then after you make those changes in the bm3 software, you have to flash again. finally, if your car is already warm, cold start does not go into effect.
__________________
M235i rwd 6mt
|
Appreciate
0
|
05-18-2022, 09:05 AM | #5 | ||
Private
17
Rep 98
Posts |
Quote:
Quote:
I can smell the fuel, it's not over whelming but neither was it on my '14 car. in my bm3 software i turned cold start off before i started it this morning and no change, i'm going to post a video to this thread. yesterday when i started the car for the first time the cold start setting was "oem" so i've tried both options within bm3. see the video i post in thread |
||
Appreciate
0
|
05-19-2022, 04:50 PM | #8 |
Second Lieutenant
117
Rep 243
Posts |
matthewcassity Some maybe dumb questions but are you sure the valve is opening up on your exhaust? Peek in there to see. Also, you are 100% sure you have the M perf axle back?
If it's closed, you wont get much volume vs if it were fully open. Do you have a way to set it to open on command to see if it is functional? Like BimmerLink or MHD wheel control? As a last resort you can physically check if you have a catless downpipe. They may have mixed something up, you never know. To do so, unbolt the flex pipe that connects to the downpipe and move it enough just to peek in there. If you see any catalytic material you found your issue.. I'm just brainstorming out loud here trying to help you out buddy.
__________________
'15 235i - Moddedededed
|
Appreciate
0
|
05-19-2022, 05:07 PM | #9 |
Second Lieutenant
117
Rep 243
Posts |
https://youtube.com/shorts/ExRIR3tAqgY?feature=share
Here's a semi cold start on catless , no resonator, remus axle back with valve open. matthewcassity
__________________
'15 235i - Moddedededed
|
Appreciate
0
|
05-19-2022, 08:22 PM | #10 | ||
Private
17
Rep 98
Posts |
Quote:
Quote:
|
||
Appreciate
1
MLJR235116.50 |
05-20-2022, 12:44 PM | #11 |
Second Lieutenant
117
Rep 243
Posts |
https://youtube.com/shorts/ExRIR3tAqgY?feature=share matthewcassity
should be available to view. Iphone doesn't capture loudness well but yeah you should be pretty loud with your current setup.
__________________
'15 235i - Moddedededed
|
Appreciate
0
|
05-21-2022, 08:31 AM | #12 | |
Private
17
Rep 98
Posts |
Quote:
Also, I haven't coded the flaps to be open 24/7 so i'm not sure what is going on lol |
|
Appreciate
0
|
Post Reply |
Bookmarks |
|
|