E92 – Akrapovic Exhaust System


By John Thorne – Wed, 26 Aug 2009 17:04


A lot of people ask me how Thorney Motorsport started andhow I got into car tuning and as with a lot of people in this industry my storyis pretty similar; mad keen on cars, modified and tuned my own cars thenfriends cars, then set up on my own, all pretty typical. However where I thinkThorney Motorsport and myself are a typical is what we think of the tuningindustry generally, in short its crap. Before I started Thorney Motorsport Iworked in the City as a equities sales and analyst – that’s stockbroker for theDaily Mail readers among you and the City is a pretty unpleasant place to work,the hours are long and antisocial, the people you work with are violentlymercenary and will happily break your legs for a percentage but the money isgood and means you can spend it all on tuning cars. For all its faults the Cityis good at one thing, its inability to tolerate people who lie; get caughtmisleading someone and justice is harsh and swift – you’re out

That’s all very interesting but what the hell does that haveto do with the tuning industry? Well never in the history of business modelshas an entire industry seems to be based on bullshit, I know that sounds harshbut try to think of another industry where almost the entire product range isbased on unsubstantiated claims? I’ve lost track of the amount of customers whocome here with horror stories of being offered one thing and walking out withanother only to have it explained as an issue regarding the weather ortechnical differences with the model or any other excuse that can be made upand it frustrates all of us here. I’m not suggesting we are TMS are Gods, weall make mistakes and we try to deal with any that we make to make sure thecustomer gets what they want but when it comes to tuning products, lets justsay we are pretty dubious on any claims made.


Its for this reason that we race, doesn’t matter what thedyno says or how fast you claim the car is on track no-one cares except theclock, it doesn’t have an ego or marketing aim, if you win you win – simple.Its also for this reason that we spend so much of our time at TMS developingour own product, currently 22% of our turnover is spent developing new ways tomaximise BMW’s performance, most of them don’t work or certainly don’t workwell enough to sell with good conscience but those that do work, work damn welland we are proud of it. This is a lot of money to invest but it’s a necessityof developing product you can trust in and we hope people can trust us. Bottomline, TMS only supplies product that we have developed directly with thesupplier – it’s the only way we can guarantee that the product does what issays it does.


With this in mind it is with some trepidation when we areapproached with a new product, typically we are very wary and any supplier mustagree to an extensive testing process before we even think about supplying it,for us our reputation is paramount but for the first time in 5 years we finallygot to see a product that pretty much left us open mouthed. Step forward theAkrapovic titanium race exhaust for the E92 M3.

TMS has a long standing and successful relationship withMilltek Sport, they work with us to create and supply the finest exhausts forthe BMW range but they work exclusively in steel so when Akrapovic come alongwith a titanium road system we are genuinely intrigued. We’re intrigued becausetitanium whilst extremely light is a right pain to use on exhausts. Titanium isvery brittle especially at high temperatures and as a result pretty much everytitanium exhaust we used (typically on race cars) barely lasted a season beforeit needed re-welding or throwing away. Despite its weakness’s it still remainsthe Holy Grail in exhaust development, as the lack of weight is such a strongaspect to work with.


Now Akrapovic have a dominant reputation in the motorbikeWorld but in the car market they are pretty unheard of so when the suppliersroll up with this new system we are our usual cautious selves, however thestatistics are just too mouth watering to ignore – a 29kg weight saving overOEM – that’s double the saving of a stainless steel system and one of thehighest weight savings we’ve ever seen. OK, so we’re begrudgingly complimentaryat this point (we try not to show it of course) so next up is build quality.Bugger, I’ve not seen welding quite like it, actually yes I have on a YamahaMoto GP swing arm…. which was made from titanium and cost £40k, the Akrapovicwas literally a work of art. Finally we looked at power, Akrapovic claim a22bhp gain from fitting the exhaust even without remapping it which we thoughtwas a sensible claim from what we’ve seen in testing the Milltek exhausts – theE92 M3 loves a decent exhaust.

Akrapovic claim to deal with the difficulties of working intitanium by specifying their own unique grade 37 XT titanium alloy which istheir own blend (think KFC but less tasty) and a highly guarded secret. Akrapovicthen extrude the alloy in house and either hydra form (very expensive usinghigh pressure water) or CNC bend into the required shapes, they claim thematerial is three times stronger than any other titanium on the market.

As with all product meetings its all smiles and “yes it’llfit very easily, no we never have warranty claims” etc but the proof for us isthe supply and first fit, typically things go wrong at this point. However withthe Akrapovic the process began with the same effect as it ended; quietcomments of admiration – and that was just the packaging!

Everything about the system drew admiration, it sat on thefloor of my office and everyone couldn’t help themselves but pick it up andmarvel at the lightweight. Closer inspection of the rear tips revealed 11separate pieces in their construction, the attention to detail is astounding.In many respects we didn’t want to fit it – it was that impressive.

At this point I’d happily share a detailed fittingexplanation but the fact is it bolted on without even a glance at theinstructions (which were on a DVD not a manky piece of paper) and the carsfirst fire up even stopped people in the office on the phone, the guy I wasspeaking to actually said “blimey, what’s that in the background”. However itwasn’t that loud, if truth were told I was a bit disappointed, for the £4500the system cost (yes, that’s not a typo – £4500 smackers) I expected a NASCARin the workshop and what I got was a part Ferrari/part E39 M5 type of noise,which surprised me. I was in the minority though, the rest of the staff allcalled me deaf and a “miserable git” when I shared my views but that’s how Ifelt. I felt the same after the first test drive, with the windows up theexhaust was barely audible through the sound insulation and for that kind ofmoney I wanted it to shout “LISTEN TO ME I’VE JUST COST YOU £4500” and I didn’tget it. This does highlight an issue with exhausts; I mean do you want it tosound good to other people or to yourself? The near round of applause the TMSteam gave it when I drove off would suggest that the external noise was theaural equivalent of an orgasm but inside the cabin it all felt a bit muted,calm even.

Fast forward 3 days, 500 miles and a record breaking tripfrom Cornwall to Milton Keynes at 2am and my faith my opinion was reversed,this car now sounds absolutely stunning. I always thought that anyone who boughtan exhaust purely for noise and not power was missing the point a bit but now Iget it, a really good exhaust can really make a car. The E92 M3’s biggest issue(other than crap handling) is its complete lack of character, it does the jobbut gives you no real feeling of soul, bolt the Akrapovic on and its suddenlyinjected with an Austin Powers level of Mojo – yeah baby!

I even caught myself blipping the throttle at traffic lightsthis morning; I mean how sad is that? It sounds nothing like a stainless steelsystem, there is a Ferrari type wail even at low RPM but still seems to givethat V8 thump higher up the rev range, its almost two systems in one.

OK, so it sounds better than sex, who cares, what aboutpower? Well, Akrapovic claim 22bhp and we got 21bhp over 9 runs on the dyno(same day before and after runs as usual) so that looks pretty accurate. Itcertainly feels a lot quicker through the rev range especially, very similar toa remap on its own. The car is now up to 460bhp and we’ve still got stage 2mapping to finalise so we’re getting closer and closer to a 475bhp E92 M3 (racecar will have 500bhp in race trim, but that’s next year).

BMW_DYNO_CHART.jpg E92 M3 Dyno Chart This dyno chart is a BMW E92 M3 with the Akrapovic full system being the only performance upgrade on the car.
Its not often we’re blown over by a product we’ve had nohand in the development, we can’t claim any input or any real opinion in itsdesign but its the first tuning product I’ve seen in 5 years that has tickedevery box we can think of and that’s worth sharing. Yes its bloody expensiveand yes it means that not many will sell but for those who get one I doubtyou’ll spend better money on your E92 M3, really.



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