[UltraMagneticAL]

since akrapovic's base m2 exhaust already has two pipes running down the length of the car, it seems engineering would be limited to the collector portion of the exhaust where the n55 uses a y-collector to downpipe versus individual collectors on the s55's.

if akrapovic could make the midpipe available while reusing the axle-back section of the m2 base, this could save some of us base m2 akra owners upgrading to the m2c very happy.

i won't be getting mine for a while, so if anyone in SoCal wants to cut their exhaust to test fit this - let's talk.

[Slaney]

I'm excited to see what they can make it sound like. Seemed like they had one of the few systems that actually gave you a slight power boost in the OG M2 versus MPE which does nothing but make more noise...

[MR.]

Akrapovic will start with a clean sheet on the exhaust for the M2C. They will of course use info from the M2 and M4 to make something work for the M2C, but since there is no a OPF, different tune and engine, and the car is shorter than the M4 they will start with a clean sheet.

MR

[SeanWRT]

Originally Posted by UltraMagneticAL

since akrapovic's base m2 exhaust already has two pipes running down the length of the car, it seems engineering would be limited to the collector portion of the exhaust where the n55 uses a y-collector to downpipe versus individual collectors on the s55's.

if Akrapovic could make the midpipe available while reusing the axle-back section of the m2 base, this could save some of us base m2 akra owners upgrading to the m2c very happy.

Akrapovic wouldn't do it even if they easily can. Akra surely doesn't want to see people buying second hand M2 OG exhaust and just order a front pipe from the factory.

There is not much, if any at all, R&D and new tooling involved to create the M2C specific system.

[Robin_NL]

Originally Posted by SeanWRT

.

There is not much, if any at all, R&D and new tooling involved to create the M2C specific system.

As MR already pointed out, shorter car and the OPF....

Cheers
Robin

[SeanWRT]

Originally Posted by Robin_NL

As MR already pointed out, shorter car and the OPF....

Cheers
Robin

He was comparing M2C and M4. The comparison should really be M2 OG vs M2C. There is nothing shorter here.

[Robin_NL]

Originally Posted by SeanWRT

He was comparing M2C and M4. The comparison should really be M2 OG vs M2C. There is nothing shorter here.

That's correct, but OG M2 vs M2C = N55 vs S55 with OPF...so I don't get it?

Cheers
Robin

[Robin_NL]

Originally Posted by SeanWRT

He was comparing M2C and M4. The comparison should really be M2 OG vs M2C. There is nothing shorter here.

That's correct, but OG M2 vs M2C = N55 vs S55 with OPF...so I don't get it?

Originally Posted by MR.

They will of course use info from the M2 and M4 to make something work for the M2C, but since there is no a OPF, different tune and engine, and the car is shorter than the M4 they will start with a clean sheet.

MR

Cheers
Robin

[SeanWRT]

@Robin_NL I assume Akrapovic doesn't have to add particle filter like OEM does. Meaning M2 OG akra system can be fitted to M2C with new front merger pipe. They're not likely to do that as that's not in their interests.

[Robin_NL]

Originally Posted by SeanWRT

@Robin_NL I assume Akrapovic doesn't have to add particle filter like OEM does. Meaning M2 OG akra system can be fitted to M2C with new front merger pipe. They're not likely to do that as that's not in their interests.

OK, it sounds like it's easier said than done (?)

Where are those ceramic OPF things situated in the 'pipeline'?

Cheers
Robin

[MR.]

Originally Posted by SeanWRT

@Robin_NL I assume Akrapovic doesn't have to add particle filter like OEM does. Meaning M2 OG akra system can be fitted to M2C with new front merger pipe. They're not likely to do that as that's not in their interests.

They have to if they want to sell it in Europe with the right kind of certification. I think the set up from them will be as follows:

- Full catback system for the world excluding EU
- Slip-on kit for the EU

They will offer the carbon parts and downpipes for the full system and that is about it. If you then order the full system and fit it on a EU car, it is your problem how to deal with it and make it "legal". Not theirs...

They will run a full development and come up with a brand new system. That is how they work normally.

MR

[MR.]

Originally Posted by Robin_NL

OK, it sounds like it's easier said than done (?)

Where are those ceramic OPF things situated in the 'pipeline'?

Cheers
Robin

It is as follows:

Engine, down pipes, at the end of the down pipe you have the extra OPF sensors, then about 60 cm of nothing including a bend, and then one OPF in either pipe.

After that a center damper, a bit more pipe and the end damper with the valves. You can remove the system completely until the end of the down pipes, but you have to someone fool the OPF sensors which are there. They will measure a flow which is different than normal. You can of course stay within the values set by BMW, but that is hard, not impossible.

You can also replace the down pipes but then you have to fool all the sensors somehow. The HKS sport down pipe on the M2 did that nicely and therefore a tune was not needed. For the EU it will be hard to replace the exhaust without not including the OPF. Slip-on is therefore the best and easiest option for the European market. This is like the MPE and cuts both pipes after the mid damper and replaces the end damper.

Only thing is that for the German market the slip-on is not allowed to be louder than the standard kit and is not allowed to have a remote, so every exhaust needs to have something similar to the Akrapovic controller system on the M2. This is a system fitted next to the amplifier and ASD in the back of the car and controls the flap similarly to what the ECU asks from the normal exhaust. Not the crap system of the MPE with that remote, but no remote and the car determines when the valve opens (or your AWRON display).

If you want to know more, drop me a message, and I will call you explaining it

MR

[Robin_NL]

Tot zover helder verhaal Marc, dank voor de info.

Cheers
Robin

[hellrotm]

Originally Posted by MR.

It is as follows:

Engine, down pipes, at the end of the down pipe you have the extra OPF sensors, then about 60 cm of nothing including a bend, and then one OPF in either pipe.

After that a center damper, a bit more pipe and the end damper with the valves. You can remove the system completely until the end of the down pipes, but you have to someone fool the OPF sensors which are there. They will measure a flow which is different than normal. You can of course stay within the values set by BMW, but that is hard, not impossible.

You can also replace the down pipes but then you have to fool all the sensors somehow. The HKS sport down pipe on the M2 did that nicely and therefore a tune was not needed. For the EU it will be hard to replace the exhaust without not including the OPF. Slip-on is therefore the best and easiest option for the European market. This is like the MPE and cuts both pipes after the mid damper and replaces the end damper.

Only thing is that for the German market the slip-on is not allowed to be louder than the standard kit and is not allowed to have a remote, so every exhaust needs to have something similar to the Akrapovic controller system on the M2. This is a system fitted next to the amplifier and ASD in the back of the car and controls the flap similarly to what the ECU asks from the normal exhaust. Not the crap system of the MPE with that remote, but no remote and the car determines when the valve opens (or your AWRON display).

If you want to know more, drop me a message, and I will call you explaining it

MR

I feel sorry for EU market. Not just for this car, but future models as well. Sounds like a real pain in the ass.

[Robin_NL]

Originally Posted by hellrotm

I feel sorry for EU market. Not just for this car, but future models as well. Sounds like a real pain in the ass.

Thanks, but actually no week goes by (and I do not drive my M2 often, only 7500 miles a year) that I don't see my speedometer touching 135mph/220kmh.

Cheers
Robin

[ingmv]

Are there any news yet ?

[UltraMagneticAL]

Originally Posted by SeanWRT

@Robin_NL I assume Akrapovic doesn't have to add particle filter like OEM does. Meaning M2 OG akra system can be fitted to M2C with new front merger pipe. They're not likely to do that as that's not in their interests.

i was thinking about this, and we can probably cut the merger of the akra and a few cm in front of the secondary cats of the stock exhaust, then use the OEM clamps to attach them. i'll try to find a caliper and get outside diameter of the akra pipes later today

another thing i see is that akra's m2 tailpipe exit routing differs from the m4 exit. i don't think it makes too big of a performance issue since the m4 pipe goes from 1 pipe to 2 tips after the flap w/ an aux pipe going thru the muffler for when the flap is closed. Whereas the m2 exit has one tip after the flap, and a second pipe routes thru the muffler before going out the second tip.

[MR.]

Originally Posted by ingmv

Are there any news yet ?

Not yet... Give me three weeks and I have some news for you guys The first news will come early October.

MR

[UltraMagneticAL]

i measured the exhaust this morning and the pipes by the collector are 65mm/2.5". i think i saw someone post that the m2c pipes are also 2.5". repurposing my akra exhaust might be as easy as cutting up the stock exhaust in front of the secondary cats and forward-exhaust hanger leaving a flanged nub, cutting off the collector of the OG M2 akra exhaust, then mating the flanged nub to the akra midpipe w/ BMW's clamps pn 18307536426.

[F87_LCI]

UltraMagneticAL you will be very lucky if you can make this work!! Have my fingers crossed for you as you could then divert funds from buying a new Akra to a lot of other goodies!!

[ryem3]

Originally Posted by UltraMagneticAL

i measured the exhaust this morning and the pipes by the collector are 65mm/2.5". i think i saw someone post that the m2c pipes are also 2.5". repurposing my akra exhaust might be as easy as cutting up the stock exhaust in front of the secondary cats and forward-exhaust hanger leaving a flanged nub, cutting off the collector of the OG M2 akra exhaust, then mating the flanged nub to the akra midpipe w/ BMW's clamps pn 18307536426.

We might also wonder how easy it would be to repurpose the M performance exhaust...

[UltraMagneticAL]

Originally Posted by ryem3

We might also wonder how easy it would be to repurpose the M performance exhaust...

you won't be able to as easily. the MPE is one pipe from the DP, so unless AA makes a single pipe midpipe for M2C like they did for the M4, then the MPE won't work.