When 620bhp just isn’t enough

Words Kim Wheeler/Jeff Heywood – Photos Kim Wheeler

Club member Kim Wheeler loves his fast BMWs, being a self confessed petrolhead and serial modifier. We have already featured his amazing supercharged E92 M3 within the pages of Straight Six, but it seems that sending 620bhp through the rear wheels of an M3 just isn’t enough. Would the feisty M2 Competition, equipped with the eminently tuneable S55, be the correct choice for Kim to replace his M3? Here’s Kim’s adventure in his quest for even more brake horsepower.

Kim’s M2 Competition is a handsome beast, the F87 shape suiting the Hockenheim Silver paint finish and smoke silver wheels

Iam guilty on all charges of loving fast BMWs, and this is my story of building a very fast BMW, along with the triumphs and disappointments that go with these projects.

My passion, because that’s what it is, initially started with an E92 M3. I had extensively modified the M3, and with the aid of an ESS Supercharger, the car was producing 620bhp and was very quick. The car was featured a few years ago in Straight Six after I submitted an article about the build. Unfortunately, the car’s peak power was in the higher rev range, thanks to the nature of the S65 V8 engine. To add 99 octane onto the controversy fire, the S65 isn’t very torquey at low RPM either…

When BMW launched the M2 Competition with the twin turbo S55 engine, as fitted to the F80 and F82 M3 and M4, I sat up and took notice. As did the motoring press, who lauded both its performance and handling over the original M2. Having a twin-turbo forced induction system, the M2 Competition is very torquey lower down in the rev range. It can be easily tuned to eye-watering power levels, too. It’s a totally different power delivery compared to the S65 in the E92 M3, making the M2 Competition more ‘driveable’ for some, as it produces quite a bit more power lower down in the rev range. No more wringing the neck of the V8 to over 7000rpm to get it going.

I had already been interested in the new M2 Competition over a year ago, but I wasn’t really in a position to change my car at that time. However, as time moved on my situation changed, I decided to part with the E92 M3 and started looking for an M2 Competition. As usual, finding a nearly new car with the right spec and in the right colour was proving difficult. And anything remotely suitable was located in the outer reaches of the UK. I therefore decided to buy new, and went off to see my local BMW dealer in Norwich.

I sat down and talked business with the same salesman who sold me my E92 seven years ago. To cut a long story short, after a test drive, the spec was chosen and the order was placed. I went for Hockenheim Silver with smoke finish alloy wheels, DCT gearbox and the (larger) M Sport brake set up. Then the wait began for delivery. Six weeks later there she was in the showroom, looking fabulous. I fired up my M2 Competition and drove home like I was Driving Miss Daisy, worried about stone chips and other drivers colliding into my brand new car. Fortunately, I made it home in one piece with no problems.

My first job was to remove the little black plastic wheel arch trims. These were not fitted to the car I test drove and I was surprised to see them on mine. Apparently, they were a last minute retrofit by BMW to meet TÜV regulations as the wheels protruded too far beyond the arches. They completely spoiled the look of the car, so off they came. After figuring out how they were fixed in place, it was an easy job to remove them. Each was held on with just three

The view 99.9% of motorists will see of Kim’s M2 Competition, those quad Akrapovic cannons give a clue to the potency of this M car

screws. The next job was to sort the stance and fill the wheel arches out. I had some wheel spacers that were from my E92 and fortunately they fitted, 15mm fronts and 12mm at the rear. They filled out the arches nicely and after fitting Eibach lowering springs the car’s stance was perfect. The only downside was that the car now sat lower than the minimum height of my jack, so I had to buy a new low-entry jack to get under the car. The final task in sorting out the M2 Competition’s cosmetics was to get paint protection film (PPF) applied to the front, to lessen the effects of stone chips and gravel rash. I chose a reputable installer, and the front was duly protected with paint film. I also had the paintwork protected with a ceramic coating, which makes the car far easier to clean. The paintwork beading is impressive after washing.

I then drove the car carefully during the 1200 mile running-in period, after which an oil service was carried out by the dealer. It was then that I could start

Under the bonnet of Kim’s M2 Competition is where the magic has taken place, although the engine bay looks pretty stock bar the Wagner Tuning intercooler…

Kim has kept the M2’s interior stock, although the little button to the left of the gearlever tells you this is no ordinary M2 Competition The carbon tips on the tailpipes of the Akrapovic Evolution titanium exhaust fit in nicely with the black trim of Kim’s M2 The Wagner Tuning Intercooler is a large but stealthy addition under the bonnet of the M2 Competition

to use the car to its full potential. The car felt quick and the low down power and torque was very welcome after my M3, but coming from a 620hp car, I felt it lacked a little overall oomph. In standard form, the M2 Competition has just over 404bhp and 405lb ft of torque at its disposal. Not bad, but room for improvement. However I was aware that as soon as I carried out any modifications to the car the warranty would be void, but I was prepared to take the risk in pursuit of more power.

I had already had a discussion with Aaron, the proprietor of A Reeve Performance, about upping the power levels. He had done numerous upgrades to many S55-equipped M3 and M4s, so we agreed on a course of action for my car. The first thing to address was the crankhub issue, which is a well known S55 weak point and becomes worse with higher powered cars. Basically, the timing sprocket is just clamped to the crank and, with no Woodruff key to stop them turning independently, the front gear has been known to slip and cause timing misalignment. One fix is to install a solid one piece hub which can’t slip, which is what Aaron fitted onto the crank.

The next step was to install an Akrapovic Evolution titanium exhaust along with cat-less downpipes and an ECU tune. The Akrapovic system and downpipes were fitted, but we needed to bypass the Otto Particulate Filter (OPF) as the car would go into limp-home mode. This was achieved with a clever little device which fools the engine ECU into thinking the OPF filter is still operating, so no limp-home mode. Aaron then plugged in the laptop to initiate the dyno tune of the ECU…but oh no, disaster! Unbeknown to any of us, Aaron included, the later cars from June onwards had been fitted with an encrypted ECU which was locked and couldn’t be accessed. Extensive trawling of the forums confirmed that no one could access these later ECUs, so credit to Bosch engineering for some excellent encryption work. But it was back to the drawing board for us.

The short-term solution was to fit a JB1 piggyback tuning box, and then wait to see if any of the tuning wizards could crack the ECU. The box was duly fitted and the car was noticeably quicker, we achieved 465bhp and 453lb ft torque at the flywheel. The sound from the Akrapovic exhaust was fabulous, too. Months passed and it seemed that no one was having any luck with the encrypted ECUs. Then a few months ago, Straight Six magazine did a feature on the 720bhp G Power M2 Competition. Wow, the car was a later model like mine and somehow they had succeeded in tuning the car to crazy power levels. I was in like Flynn.

Numerous emails and WhatsApp chats subsequently took place with G Power’s sales manager and they confirmed they could tune my car. The downside was that a) they needed it in Germany (G Power’s located near Munich in Bavaria) and b) they wanted my M2 for at least a week. I looked into various ways

The tank and brains for the methanol injection system are stored in the boot

of getting the car to them, but in the end I decided against it as the logistics were too complex and costly.

So, thinking cap on again. What if we could swap out the encrypted ECU for a non-encrypted one from an earlier car? Could we tune it then? The question was posed to Aaron and he said it was possible, but would need a lot of other work and other modules changing. Basically it was a huge task. Having come this far I thought “in for a penny, in for a pound” and I sourced an earlier

ECU along with various other modules associated with the engine ECU. The strip out and rebuild could then commence. We enlisted the help of a coding expert and between us everything was changed over to the new modules and we ensured they all talked to each other in the CanBus system. Well, nearly all of it…

So, would it start? Yes, it did. Would it drive? No it wouldn’t. More work needed. The DCT’s ECU wouldn’t talk to the car, so therefore it wouldn’t budge. More coding, would it drive? Yes, it would. Success, we had done it.

We impatiently hooked my car onto the dyno, ECU accessed and a tune to 532bhp and 494lb ft torque was achieved. The car was now very quick. But can we go higher like the G Power M2 Competition? Yes we can.

On recommendation from Aaron, I ordered an upgraded air charge cooler from Wagner Tuning, along with a larger than standard Forge Engineering charge cooler radiator. Keeping the charge air as cool as possible is crucial to achieving a higher power output on a turbo engine. Larger surface areas of cooling fins help to keep the charge air temperatures lower than what the standard equipment can achieve. I also ordered larger charge pipes and a larger intake J-pipe, colder running plugs, upgraded ITG Profilter drop in panel air filters, hybrid turbos from TTE and a methanol injection system. Well I did say in for a penny in for a pound. Hybrid turbos increase boost beyond what the standard turbos produce and the methanol injection system helps to lower combustion temperatures even more, preventing knock or detonation. The larger charge pipes allow more air to flow from the bigger turbos as does the larger J-pipe inlet. The TTE turbos are built to order so there was a bit of a wait before I received them. They are basically the original turbos completely re-machined and enlarged. A whole three months later and they finally arrived back from Germany and the car was back in the workshop and all the parts were fitted.

Well, what will all that work and expense produce? Onto the MAHA MSR 500 dyno again at A Reeve Performance and this time my M2 produced 665bhp and 502lb ft of torque on Map 1 with methanol. When switched to Map 2 with no methanol for more sedate driving, it still gave an impressive 560bhp and 516lb ft of torque.

The S55 engine is a fantastic piece of engineering to take this level of power, it’s insanely fast and the acceleration literally pins you back in your seat. It is quite breathtaking. To extract much more power you need forged engine internals, but near 700bhp is within the engine’s capabilities. We ran out of time, so by the time you have read this the car will have been back in for more fine tuning with the aim of seeing a genuine 700bhp and 590lb ft of torque. Why? Because we can, and because we are BMW tuning enthusiasts.

Was it worth it? Yes it was. Did it cost a lot? Yes it did. My missus is just about still talking to me. We did it as a project to show you can overcome obstacles with persistence, time, a great knowledge pool, and achieve fantastic results. I can see myself owning this car for many years to come and for as long as I keep my licence.

Here is the dyno printout we received just as the article was going to press, showing Kim’s M2 Competition achieved a corrected brake-horsepower figure of 719.8bhp, 610.2bhp at the wheels

What’s next?

Maybe some coilovers to keep it in a straight line and help it go round corners on track. Next year, possibly. I won’t suggest this at the moment to she who must be obeyed, I want to stay married for at least a few more years. In the meantime, I hope you enjoyed reading about my build and it encourages others to have a go.

Further update: A few weeks after the initial power runs, Kim took the car back to A Reeve Performance for another session on the MAHA dyno. Kim’s M2 Competition achieved 719.8bhp (corrected), so I think you can safely say he has well and truly achieved his 700bhp goal!