[Uni-Rapide]

I have a late 2018 F30 340i with OPF (unfortunately) and got my eye on the REMUS cat-back. I contacted a local dealer and also REMUS in Austria and they both said the cat-back doesn't fit my car.
Call me stubborn but I find it hard to believe that's true but on the other hand I don't want to risk spending nearly EUR2k to find out I was wrong.
Does anyone have experience with this?

As far as I know the OPF is part of the front/mid pipe after the downpipe so a pre-OPF cat-back system should fit. Or do you think I need another downpipe as well?
And yes I do realise that deleting the OPF will throw a CEL.
Thanks in advance for the help!

[Tengocity]

I would be 99.9% in agreement with you. Past the OPF the systems are fundamentally the same.

There was someone trying to sell a full system on eBay for a while, so maybe worth a look to see if that's still available. If it is then even less risk to try it.

[mrberry]

i believe it fits but it causes engine management light or something like that to stay on. i bought one from a member here and that was the reason he was selling if i remember right. the light would come on and as his car was under warranty he didn't want any issues . not sure if it affected the day to day drive

[Tengocity]

Originally Posted by mrberry

i believe it fits but it causes engine management light or something like that to stay on. i bought one from a member here and that was the reason he was selling if i remember right. the light would come on and as his car was under warranty he didn't want any issues . not sure if it affected the day to day drive

I don't see how it can show a CEL. There's no sensors in the back box area, and it doesn't do anything for emissions.
The issue come if you try to fit a full system, as the OPFs can't just be gotten rid of like you can with secondary cats.

[Chris ABP]

I have a 2019 340i with PPF/GPF and I’ve fitted a full BMW MPPSK exhaust which removes the GPF and goes from the bottom of the down pipe through to the back of the car.
Car throws a CEL about once every 600 miles or so with a spurious code but I delete the code and then all good again for 600 miles. Have a service coming up and then it’s being mapped which will eliminate the CEL issue.
But I see no reason why the Remus won’t fit.

[mrberry]

Originally Posted by Tengocity

I don't see how it can show a CEL. There's no sensors in the back box area, and it doesn't do anything for emissions.
The issue come if you try to fit a full system, as the OPFs can't just be gotten rid of like you can with secondary cats.

i would have guessed its something to do with pressure and its calculated with opf being on. i know of someone who just straight piped acrossed the opf bit thinking he would be okay as he couldn't see a sensor but he keeps getting the engine light so is getting it mapped out

[Uni-Rapide]

Thanks for the answers!
I now feel confident enough to buy the REMUS cat-back system

As far as I understand it there is a back pressure measurement between the cat and OPF so as soon as you remove the OPF there will be less back pressure and that triggers the CEL.

[Jacob117]

Hi,
I have an F31 340i with OPF and mounted Remus axle back, but I am considering mounting Remus cat back midpipe, can you confirm it fits?

\\Jacob

[Uni-Rapide]

Originally Posted by Jacob117

Hi,
I have an F31 340i with OPF and mounted Remus axle back, but I am considering mounting Remus cat back midpipe, can you confirm it fits?

\\Jacob

If you buy the two pipes below, yes it will fit between the downpipe and backbox:

[Jacob117]

Thank you, that was exactly what I wanted to do.

And as i understand I can code the OPF out with MHD, did you do the same with BM3?

[Uni-Rapide]

Originally Posted by Jacob117

Thank you, that was exactly what I wanted to do.

And as i understand I can code the OPF out with MHD, did you do the same with BM3?

Correct!

[Danj94]

Originally Posted by Chris ABP

I have a 2019 340i with PPF/GPF and I’ve fitted a full BMW MPPSK exhaust which removes the GPF and goes from the bottom of the down pipe through to the back of the car.
Car throws a CEL about once every 600 miles or so with a spurious code but I delete the code and then all good again for 600 miles. Have a service coming up and then it’s being mapped which will eliminate the CEL issue.
But I see no reason why the Remus won’t fit.

Hi I appreciate this is an old post but if you're still around..

I have a 2019 with OPF filter in mid pipe, am I right in thinking the MPPSK or MPE back box would fit on the mid pipe, keeping the OPF in place.

I dont want to remove the OPF for insurance/MOT reasons.

[Jacob117]

Hi,
the MPE back box will fit, but it will through a engine code some times because of missing back pressure. Thats why the Remus is good because it has the valve that open/closes, so it doesnet give any codes. The MPPSK has the valve also, but then you would have to do some modifications to fit it, because its straight from downpipe and back.

[iustinrusu]

Hi,

I also have a 2018 F30 340ix with OPF and I'm interested in buying a REMUS cat-back system for my car. Had the same question, will it fit? Since you already installed the system, could you answer some questons so I could finally wrap my head around this and get it over with, I'm tired of calling mechanics and getting ambiguous answers.

1. Will the REMUS cat-back exhaust system fit on my OPF 340i, even though it's advertised as not compatible?

2. I also thought that maybe downpipes on OPF models are different than the downpipes on non OPF models. Is this true? Will the REMUS exhaust connect alright with the stock downpipe?

3. Would like to buy a Wagner 200 cell DP. Will it fit my car, even though Wagner clearly states on their site that the DP is not compatible with OPF vehicles? What would be the incompatibility? The connection between the DP and the exhaust? That would be solved by installing the REMUS exhaust. Or is is the connection between the DP and the engine? Maybe OPF model DP connect differently to the engine than the non OPF models? I'm not sure, maybe someone here knows, would be greatly appreciated!

Thank you a lot!

[Lorcan]

Email Mike at Motech motechperformancesales@gmail.com - he sells lots of Remus exhausts so will know the answer to these questions off the top of his head.

Generally speaking OPF cars have one, sometimes two, pressure sensors in addition to the usual O2 stuff and it's the location of these that can cause changes to the pipe design, different diameters and so on.

If you fancy doing a bit of digging yourself, hop on to realoem.com with VIN (last 7) for both OPF and pre-OPF cars and compare the part numbers for the downpipes etc.

[iustinrusu]

Unfortunately he couldn't help me, said he only did Remus axle-backs.

In the meanwhile, I bought a Supersprint catless DP (for OPF model). The only question that remains right now is, will the Remus cat-back exhaust system fit with the Supersprint DP? Since it's for the OPF models, should connect the same as the stock downpipe. So basically the question could also be, will the Remus cat-back exhaust system fit the stock downpipe for OPF models? I don't want to spend 2k only to go through the hassle of returning it if it won't fit.

Thanks in advance for the help!

[Uni-Rapide]

Originally Posted by iustinrusu

Hi,

I also have a 2018 F30 340ix with OPF and I'm interested in buying a REMUS cat-back system for my car. Had the same question, will it fit? Since you already installed the system, could you answer some questons so I could finally wrap my head around this and get it over with, I'm tired of calling mechanics and getting ambiguous answers.

1. Will the REMUS cat-back exhaust system fit on my OPF 340i, even though it's advertised as not compatible?

2. I also thought that maybe downpipes on OPF models are different than the downpipes on non OPF models. Is this true? Will the REMUS exhaust connect alright with the stock downpipe?

3. Would like to buy a Wagner 200 cell DP. Will it fit my car, even though Wagner clearly states on their site that the DP is not compatible with OPF vehicles? What would be the incompatibility? The connection between the DP and the exhaust? That would be solved by installing the REMUS exhaust. Or is is the connection between the DP and the engine? Maybe OPF model DP connect differently to the engine than the non OPF models? I'm not sure, maybe someone here knows, would be greatly appreciated!

Thank you a lot!

1. Yes the Remus cat back system will fit.

2. If I remember correctly the down pipes on OPF models have the connection for the back pressure sensor, that’s the difference, so yes the Remus cat back will fit the stock downpipe.

3. The Wagner downpipe will fit and the Remus cat back will fit the Wagner as well. I personally have a VRSF downpipe combined with the Remus cat back on my “OPF” 340i

[iustinrusu]

Awesome, thanks a lot for the clarifications!