[Zopperman]

Hi,

I'm picking up a 435i exhaust from another member, and he is selling the full catback. I know that others have swapped the muffler without issue, but has anyone swapped the whole catback out? I figure worst case I can just swap the mufflers.

I don't have an m-sport, so I will be trimming the bumper to fit and putting quad tips on. We'll see what happens.

Can someone educate me on the "plug"? I have read about it but I'm not sure I follow. Since this is a stock 435i exhaust will I need to decide if I want that plugged or unplugged permanently? I don't believe my car has any wiring for the plug.

Please bear with my basic questions - I have never changed an exhaust on any of my vehicles.

Thanks!

[Zopperman]

bump

[kern417]

The midpipes are a similar shape, so it will probably fit. But I can't say 100%. You'll just have to mate it up to the car and see if it all lines up. The only issue I see you might have is connecting it to your stock downpipe.

428i midpipe
http://www.realoem.com/bmw/enUS/show...diagId=18_0986



435i midpipe
http://www.realoem.com/bmw/enUS/show...diagId=18_0977



Regarding the plug, both the 428i and 435i have the same flapper. so if yours has the plug, then remove it from your stock exhaust and install it on the 435i exhaust and it'll work the same. Otherwise you don't need to do anything.

[Zopperman]

Originally Posted by kern417

The midpipes are a similar shape, so it will probably fit. But I can't say 100%. You'll just have to mate it up to the car and see if it all lines up. The only issue I see you might have is connecting it to your stock downpipe.

428i midpipe

435i midpipe

Regarding the plug, both the 428i and 435i have the same muffler. so if yours has the plug, then remove it from your stock exhaust and install it on the 435i exhaust and it'll work the same. Otherwise you don't need to do anything.

Thanks, this is really helpful. I will post back what the exhaust shop has to say.

If they have the same muffler and similar piping, what's the advantage of installing the 435 exhaust? The other threads that I had seen reported a change in exhaust pitch and sound. I am primarily doing it to wind up with quad tips and to have an exhaust that has a little more sound to it.

[kern417]

Originally Posted by Zopperman

Thanks, this is really helpful. I will post back what the exhaust shop has to say.

If they have the same muffler and similar piping, what's the advantage of installing the 435 exhaust? The other threads that I had seen reported a change in exhaust pitch and sound. I am primarily doing it to wind up with quad tips and to have an exhaust that has a little more sound to it.

I typed that wrong. I meant to say both have the same flapper, i.e. what the plug goes into. But regardless, most people do the change mostly looks. I doubt it'll change sound much.

[Zopperman]

Originally Posted by kern417

I typed that wrong. I meant to say both have the same flapper, i.e. what the plug goes into. But regardless, most people do the change mostly looks. I doubt it'll change sound much.

Thanks, that makes sense. I would rather err on the side of having it be too quiet than too loud, so hopefully this will work for what I'm trying to do.

I'm a bit nervous about cutting the bumper, but I figure worst case I get an m sport one and I'm out a bit of money to have it painted and fitted.

I don't think the 435 exhaust will line up with the stock cut out, so I'm hoping the exhaust shop can reroute the piping before the tips as needed, and get everything lined up nicely.

[yoon_209]

The n55 exhaust has a dimple on the exhaust where you cut if you want to install the mperformance exhaust.

I'm guessing the n20 engines exhaust has the same dimple. If so, you should make your cut there and use the clamp to install.

[Zopperman]

Originally Posted by yoon_209

The n55 exhaust has a dimple on the exhaust where you cut if you want to install the mperformance exhaust.

I'm guessing the n20 engines exhaust has the same dimple. If so, you should make your cut there and use the clamp to install.

So assuming my n20 has the dimple, you think I should cut the n55 exhaust at the dimple and use it from that spot down to the tips?

Is there really any advantage to running the mid pipe from the n55 or should I just swap the mufflers? Thinking now if they are basically the same part, what's the value add?

[yoon_209]

Originally Posted by Zopperman

So assuming my n20 has the dimple, you think I should cut the n55 exhaust at the dimple and use it from that spot down to the tips?

Is there really any advantage to running the mid pipe from the n55 or should I just swap the mufflers? Thinking now if they are basically the same part, what's the value add?

If your n20 has the dimple in the same location as the n55 dimple then yes.

Also i wouldnt go as far as switching out the entire stock catback from a n55 and put it on the n20. I would only do the axelback muffler.

There is probably minimal to no gains. Exhaust is all for sound and aesthetics. If you want performance from an exhaust mod, the downpipe will be the most beneficial.

There are tons of people who have done the single to dual outlet exhaust conversion. Both exhausts should have the exhaust valve actuators as well.

[Zopperman]

Originally Posted by yoon_209

If your n20 has the dimple in the same location as the n55 dimple then yes.

Also i wouldnt go as far as switching out the entire stock catback from a n55 and put it on the n20. I would only do the axelback muffler.

There is probably minimal to no gains. Exhaust is all for sound and aesthetics. If you want performance from an exhaust mod, the downpipe will be the most beneficial.

There are tons of people who have done the single to dual outlet exhaust conversion. Both exhausts should have the exhaust valve actuators as well.

Thanks. That's very helpful - I'll see if I can find the dimple and cut it there. It would make it a lot easier to transport to the exhaust shop too. I'm not expecting much of a performance gain from this, really just trying to get quad tips and a little more sound. I just bought an intake but I think the downpipe will be next, or BM3.

[yoon_209]

downpipe intake and flash tune will completely change your car

have fun

[Zopperman]

Small update for those interested.

I picked up the exhaust today, and I cut it between the center muffler and the rear muffler so that it would have less of a foot print. Figure I'm just going to have the shop weld it in place anyway, and worst case they can weld it back together.

[kern417]

Should have told everyone it's a super exclusive off-road antenna system