[Skyhigh]

To be fair, cells are just a marketing term, exactly like megapixels
I can make a cat converter with 10 cells, I ensure you. Yes, they will each be the size of the cells in a standard cat, but I don't need to tell you that - they will be only 10! 50 times better than the stock, right? 😉

[vcx]

Originally Posted by Skyhigh

Maybe you should look again





How much more proof does one need

Another relevant thread: https://f30.bimmerpost.com/forums/sh....php?t=1506433

What I don't get it that even if you select the 2017 model year (so before OPF), the Akrapovic website says that it's not EC compliant. And on the picture certificat you posted, it's related to the BM/SS/7H and not the 5H.

I wonder if the certificate you posted is maybe for the full exhaust.

Also, local resellers say on their website that it's not EC compliant.

I really wants to believe you are right, but all this is confusing.

I wonder if when you bought your it was compliant, and then maybe the law changed and it's not anymore, even without OPF?

[Skyhigh]

Note that the EC approval is for the entire Akrapovic Evo Line Exhaust system, which incorporates the subject Downpipe! (Read the Description of the "Technical Unit").
That's the P/N you see there - of the entire system. The DP is just one element of it. It's own ECE approval number is listed to the right on the sheet and also engraved on the DP itself.

As I said above - when I ordered mine, the exact same text about not being street legal was there. I specifically asked - the answer from the distributor is pasted above.
It was the exact same P/N (see also photos of mine above with the P/N marking) and the exact same EC certificate, which I downloaded 1,5 years ago. I, like many others, have been driving it without a tune ever since with a smile on my face and no CEL ever seen.

Akrapovic are just messy with their website, that's all. Or maybe it is not "street legalised" in third countries (the EC certificate is only valid for Europe as far as I know). Or there is another element of "legality" (noise?) which it no longer fulfils?
But why does someone not drop them a line and ask for explanation? It would be interesting to see their response.

One thing I am 100% sure of (based on all facts above) is that it complies with Euro 6 for emissions, hence is a legal replacement of the OEM DP from emissions point of view (for vehicles without OPF of course).

[Skyhigh]

An interesting (and somewhat informative) video, for those of you who understand German. (If not, it may still be interesting to see)

[disintegrator66]

Originally Posted by Hein Jockins

^ This is why. I just have mppsk + akra DP, and I couldn't stop smiling for several days after installation. The second I drove away, I immediately noticed an increase in torque and response. Wasn't really expecting akrapovics reported numbers to even be felt, but I was wrong. Oh and I'd buy this just for the sound.

Edit: I'm still flashing stage 1 or 2 BM3 whenever I get confirmation my DME can still be bench unlocked with BMW's latest software update from a few months ago.

You guys are killing me.....

MUST RESIST PURCHASING.... MUST RESIST PURCHASING.....

[rosstin]

I got my pre-opf dp sometime in 2019 and I'm sure their website didn't talk about re-tune then - I wouldn't have bought it if it did as I'm only mppsk.

I wonder if they just got sloppy and copied the new opf warnings to their pre-opf page?

[T_H_O_M_A_S]

Originally Posted by disintegrator66

You guys are killing me.....

MUST RESIST PURCHASING.... MUST RESIST PURCHASING.....

you could just by any dp and have a major increase ,
my m140 with stock software , went from 11.4 to 10.22 (100-200km/h) by just installing a dp and opf delete . buying it from akra is just an expensive piece of flanged tube

[Skyhigh]

...And yet the differences in the design of the expensive "flanged tube" are so obvious that you don't need to be an engineer to see how Akra have worked on improving every little detail to remove or reduce any potential bottle-neck and squeeze out every % of performance possible. Meticulous engineering is what I would call it.

But of course there are options with higher value-for-money ratio. It is not a liner progression, as always.

[T_H_O_M_A_S]

you would be very good in marketing

its just what the idiot wants to pay for it

[Skyhigh]

I realise I sound like an Akrapovic salesman
But I am not. Believe me. Just an engineer who knows good work when he sees one.

I was actually going for a HJS DP originally (I did want a HJS cat, irrespective of the pipe, due to their reputation and emissions compliance). AC Schnitzer was one level up price-wise although it is in reality a rebranded HJS + ACS customer support. Akrapovic was the most expensive and I was not going for it, despite the advantages. But then I found it with discount, which put it price-wise approximately on the level of AC Schnitzer…. And I simply could not resist.
Haven't regretted it for a minute That's all.

[disintegrator66]

Originally Posted by T_H_O_M_A_S

you could just by any dp and have a major increase ,
my m140 with stock software , went from 11.4 to 10.22 (100-200km/h) by just installing a dp and opf delete . buying it from akra is just an expensive piece of flanged tube

True, but nothing beats Akra quality/design. Back in my sportbike days I had Akra full systems on three of my bikes. I'm very familiar with the brand. Wagner seems pretty close, but they no longer offer a 300 cell option and I don't want to deal with emissions BS in my state.

[smrtypants44]

Originally Posted by Skyhigh

+20 PS, + 20Nm and even torque increase in the entire range, -0,25sec 0-100, + lower temperature and higher reliability of the turbo, + quicker spin, + better throttle response, + better sounding exhaust…..
whilst maintaining the factory warranty, all sound like a waste to you!?? Interesting. Oh well, to each their own.

An aftermarket downpipe will for sure void any warranty claims on the turbo if the dealer found out about it. Not sure why you'd think otherwise.

Also I'd like to see the before and after dyno sheet for that 20hp….

[Skyhigh]

Originally Posted by smrtypants44

An aftermarket downpipe will for sure void any warranty claims on the turbo if the dealer found out about it. Not sure why you'd think otherwise.

Also I'd like to see the before and after dyno sheet for that 20hp….

That's the difference between a tune and a hardware part - you can always go back to the stock hardware without leaving a trace.

Dyno sheets available online by different sources.
Here just one - with the HJS Downpipe (exactly the same cat, just sub-optimal DP design):

Result:


I myself can only offer before and after Dragy evidence showing reproducible 0,20-0,25 s. improvement in 0-100 time. The details are available in the thread I have already linked to. Same route, same engine software, approximately the same environmental conditions. Solely a DP replacement.
You do the math.

Waste, right?

[cxmplex]

Akrapovic is the best of the best, it's not really disputable. Downpipes I would say are almost certainly more for sound than performance. Take a look at MP, they're able to reach the same targets as PTF and MHD without a DP requirement. For more enthusiast tuning, yeah sure, it's probably needed.

[Skyhigh]

Just a note - MHD don't have a DP requirement. They have a DP recommendation.
Seeing how much of a bottle-neck it is even without a tune, it's not difficult to understand why they would highly recommend it in combination with a Stage 2.

Yes, you can achieve the same without upgrading the DP. At the cost of turbo reliability, as a minimum.

[cxmplex]

Originally Posted by Skyhigh

Just a note - MHD don't have a DP requirement. They have a DP recommendation.
Seeing how much of a bottle-neck it is even without a tune, it's not difficult to understand why they would highly recommend it in combination with a Stage 2.

Yes, you can achieve the same without upgrading the DP. At the cost of turbo reliability, as a minimum.

Understood. Although if you look the majority of this forum is either using stg 1 or a jb4, and in that case I'm not entirely sure a DP would add much benefit besides a deeper sound.

Do we have any analyzable data that shows it does? I have the AA catted DP and love it, but I'm also using stg 2 w/ hpfp, Akrapovic is even more expensive.

[Skyhigh]

Did you read/see the last few posts…? Plenty of evidence it adds both torque and power, even without any tune! Whether it is much or not much…. Everyone is free to decide.
For me it is „appreciable" and definitely more than I imagined!

[T_H_O_M_A_S]

all stages measured at pureturbo's.eu dyno

Stage 0 is stock tune with dp and opf delete : 331whp and 518wtq.
crank figures about 10 percent extra i was told by peter .
ive added the dyno sheets and dragy times .
So just adding any DP to a B58 makes a huge difference

[Hein Jockins]

In other news, my CEL came on again a week after the code was cleared the first time... I supposed even Akrapovic's high flow catted DP requires an ECU flash.

I imagine I just ignore it until I tune it? Its not like there's a "fix," its just the car has no idea what to do and its assumes its a faulty cat converter?

[Skyhigh]

I would strongly encourage you to:
1. Check the DP installation and mounting of the O2 sensors very carefully. Check if everything is tight.

2. Remove and Inspect the DP itself.

Something is not right. Tausends of B58 HJS cats sold, many in Germany as well where they have been legally registered on the car's approval.

My guess is that either of the O2 sensors (likely the second) is not mounted properly or got damaged during installation. Check their wiring connections as well.

Don't just go masking the symptom. Find the cause.

[Hein Jockins]

Originally Posted by Skyhigh

I would strongly encourage you to:
1. Check the DP installation and mounting of the O2 sensors very carefully. Check if everything is tight.

2. Remove and Inspect the DP itself.

Something is not right. Tausends of B58 HJS cats sold, many in Germany as well where they have been legally registered on the car's approval.

My guess is that either of the O2 sensors (likely the second) is not mounted properly or got damaged during installation. Check their wiring connections as well.

Don't just go masking the symptom. Find the cause.

Thank you! BMW actually did the install for me cause I was already in there for service, and there's a tech who had his own shop and was familiar with akrapovic. That said, I really don't trust BMW to do much other than oil/filter, so I'll find another shop to take it apart and inspect it.

Ideally it's just an O2 sensor, and hopefully there isn't any truth to Akrapovic's: "When installing the Akrapovič downpipe, remapping the ECU is mandatory in order to prevent potential “check engine light” warning signals." --I wouldn't be surprised if their site simply wasn't accurate or up to date. I'm awaiting an email response to get something from them addressing this.

[Skyhigh]

Please share the response once you get it.
The topic has be extensively discussed here already.
Even if they just decided not not take any legal responsibility on behalf of HJS…., this in NOT a normal situation.