Originally Posted by Mpro
I believe the Akra Slip-on with wireless doesn't get the EC approval here in Belgium (it's for the slip-on only)
Hereby an extract from the installation guide:
12. For optional Wireless kit: assemble the clamps and Valve Pipe onto the muffler’s inlet pipes, as shown (Figure 35, 36).
WARNING: use anti-seize copper paste on all clamps’ bolt and nut threads!
CAUTION: in case of combination of Slip-On and optional Wireless kit, the Akrapovič exhaust system EC type approval is not valid!
Is this correct? I really don't want any trouble with car control authorities in a few years...
I have the N55 mids too, but can't decide between Akra Slip-on + wireless and the Eisenmann Sport.
I really can't justify the extra price for the Akra, although I know it has the best quality.
First, I am in no way affiliated to Akra.
The pages and figure numbers that you mention do not correspond with my information. You probably refer to page 14 featuring Figure 7 of the "Optional Wireless Kit for the BMW 1 Series M Coupe (type E82)"
installation guide and to page 34 featuring Figure 27 of the "Slip-On, Evolution and optional Down Pipes for the BMW 1 Series M Coupe (type E82)"
Just for the record: the Akra butterfly valve of the wireless kit is a circular movable blocking plate. In 'closed valve' mode it is in vertical position, impeding the exhaust fumes from accessing the circular outer pipes. When operating 'opened valve' mode' the butterfly flips/revolves over its axis to horizontal position, perfectly in the middle of the connecting pipe (so it does not disappear, but simply no longer impedes the exhaust fumes from exiting through the outer pipes).
Without the wireless kit, the outer pipes are not used (and will remain clean) and the exhaust sound seems to be even a little quieter than the OEM 1M exhaust sound whenever the engine is under load. That might be the reason why Akra got an EC Type approval (TüV) for the 1M Slip-On (http://az79640.vo.msecnd.net/akrapov...0e3943a60a.pdf
) ...and also why those who don't opt for the wireless kit, in order to get the sporty sound on a permanent basis, grind off and remove the welded blocking plate from the connecting pipe (see the small connecting pipe on the left of Figure 27 on page 34 of the Slip-On installation guide and compare with the one featuring in Figure 7 on page 6 of the wireless installation guide). Of course the 'blocking plate removers' only use their car on a race track and in their private garden.
And that's what makes the wireless kit quite an interesting feature, as also hybris4u pointed out:
Originally Posted by hybris4u
If I buy it's probably going to be Akra with N55 mid pipes and wireless. I want to have a "sleeper" mode where I go unnoticed. Then I want the wonderful sound when the right situations or attention is wanted. The OEM exhaust is too quiet if you don't accelerate hard and that is not the best way to get attention in many situations. Meaning in suburban areas etc. So for me the combo is what do make the whole deal interesting. I would not go for any exhaust where its always loud. Not the right profile for me. Close to 40 years old and family. We all have different profiles and needs at different times in life. If you asked me the same 10 years ago I would have said loud always! ;-)
Non-wireless ("The Akra Flower Pot" with the blocking plate [base] still intact, impeding exhaust fumes to exit the outer tail pipes which bypass the axle back muffler):
Wireless (butterfly valve inside, operated at the touch of a button, to control whether exhaust fumes can also exit the outer tail pipes which bypass the axle back muffler):
Accompanied with the Akra Slip-On package comes a technical document entitled "Street-legal component approval certificate"
(nicely packed by Akra in a compact transparent plastic sleeve bag). If need be, this document can be shown to the police (if ever pulled over) or technical car control authorities, if specifically questioned about it. It might puzzle them for a moment and let you off the hook. Actually, they might even not know that you have a Dr. Jekyll and Mr. Hyde system. Of course when cops are around or you visit the technical control, you don't storm in with the valve open. So, ask yourself, don't you think that you will be more convincing if you can definitely demonstrate that you can keep the butterfly valve closed (and that you open the valve only when you're not on a public road
), than when you removed the blocking plate and you cannot demonstrate on the spot when caught red handed to quiet down the system (actually, you even attract their attention upon approach) ?
Moreover, if you opt for the wireless kit, you also still get the connecting pipe with welded blocking plate too. Let's simply nickname it "The Akra Flower Pot"
, because that's what it looks like.
May come in handy in the future: if they ever order you to remove the wireless connecting pipe (butterfly valve), simply swap it with The Akra Flower Pot. All electr(on)ic wiring can remain on board. So everybody's happy. But afterwards don't forget to bring the wireless connecting pipe to the race track for a temporary re-swap with The Akra Flower Pot.
Fair and square: if you have the slightest hesitation whatsoever, keep everything 100% OEM stock on your 1M.
Preferred place for keeping/operating the wireless control button (discreet and easy to reach when you're on the race track
- US 1M owners might eat their hearts out because they can only store their sun glasses in that spot) + you got the fringe benefit that there is an amber/orange cigarette lighter illumination surrounding the base of the button, creating some extra ambient atmosphere.
Akra butterfly valve closed (code white):
Akra butterfly valve open (code red):
Akra butterfly valve open (comparison with the inner exhaust tail pipe):