Producing a huge 620whp from its built S52 straight-six, this full-on turbocharged Z3 M Coupé is a project that has never stopped evolving and almost a decade of development has created an awesome performance machine.

From Performance BMW. Words: Elizabeth de Latour. Photos: Cris Guamanzara

The Z3 M Coupé always has been something of an oddity but that’s exactly what makes it so appealing and some people, like Ken Meisch (@z3speed4me), really like them. And Ken really likes M Coupés and Z cars in general… “Before my current turbocharged Z3 M Coupé, I had a 2001 Estoril blue S54 M Coupé. Before that another Estoril blue 1999 turbo M Coupé, and before that a black 2006 Z4 M Roadster.” And what about his first car? “That was a silver 1998 Z3 1.9,” he grins so it’s clear that he’s got the Z bug in a big way. “Cars are meant to be driven, and BMW has always called itself the creator of the Ultimate Driving Machine… that statement has to have some weight to it right?” says Ken as he explains his long-standing passion for the Bavarian brand. “Its vehicles are part luxury, part sport, until recently not outrageously priced, and definitely built well and there has always been a focus on the driver. The simplistic and raw approach to something like the M Coupé doesn’t happen much – if at all – any more,” he says and it’s easy to understand the appeal and appreciate his passion.

The Z3 1.9 Roadster seemed like the perfect cool first car for a teenage Ken (“It was way cooler to me than many other options at the time that friends were picking up, plus teenage girls love convertibles, right?” he grins) but there was something else on his mind… “Each morning going into high school I would pass a local CVS pharmacy, and someone there owned a brand new blue Z3 M Coupé. I could not take my eyes off it… I had to have one someday. Eventually, that time came a few years later,” he says with a smile.

Turbocharged Z3 M Coupé

Ken’s first Z3 M Coupé started out as a stock NA car before undergoing the turbo treatment and Ken got it to over 600whp before an unfortunate accident put an end to things and he parted everything out and moved on. “I needed an M Coupé again, and very quickly I found and purchased a local S54 model and enjoyed it for a few years, but the lingering desire for boost kept creeping into my mind,” he says. “I had an agreement with my wife that I wouldn’t do it again for a long time as I grew older, and eventually we decided that it would be okay to go down that road again. In comes M Coupé number three and this one is a keeper to me, there is nothing else like her,” he grins.

“It was originally purchased new and owned by Ben at Rogue Engineering before later being bought by one of my best friends, Rukman, back in 2004 which was when the turbo journey of this vehicle began that I have since taken over,” explains Ken. “As I’d driven it a few times before, it was literally everything I focused on mimicking on my last build, so I knew what I was getting into already. We had a gentleman’s agreement that if he were ever to sell it, I had the first – and probably the only opportunity – at taking it off his hands. And so, with some eventual convincing, I purchased it from my buddy and here we are today on turbo coupé number two, another beautiful Estoril blue example. Basically, this car is exactly everything my last one was built to be, with just some minor hardware differences. Even the base tune from the prior car is based on this build as the setups are so strikingly similar,” he says.

Turbocharged Z3 M Coupé

“The mindset for the build was to create an ultimate BMW street car with amazing reliability and drivability,” Ken tells us. “Tonnes of guys were going down the turbo route in the early 2000s but almost all of them were using standalone systems, which were also not even close to the capabilities of the options available on the market today. I wanted to be able to drive around town, go to the store, idle in traffic with no worries, never overheat, drive it to a track and home again with no problems. It had to be civilized, but also have speed when summoned upon. Jekyll and Hyde in one car that didn’t feel like it had over 600hp until you really stepped on it,” he says and he’s absolutely achieved his goal.

The project began in 2005 when the car was driven down to Florida and left in the capable hands of Nick Glantzis and his company, Technique Tuning, with Ken initially planning on getting the Stage 2+ turbo setup but the temptation for more power proved impossible to resist… “With the car out of my hands I had too much time to think… The little devil on my shoulder could not be denied and I decided to step it up and go all-out. The Technique Tuning Stage 3 ‘kit’ was born: a built motor with lower compression, bigger 60lb injectors, full exhaust etc. Nothing like this was being done at the time on a stock DME, it was truly a monumental step forward in the BMW FI community. The car started with an output of 515rwhp/500lb ft wtq at 20 psi using the original cast manifold, almost unprecedented power at the time from the S52 powerplant. The car was simply incredible,” he grins. “The mod bug as always would strike, though, and eventually a few years later the next change was a tubular manifold and upgraded V-band turbo housing, in 2007. 536whp and 478lb ft wtq was the net, not as impressive as expected and the midrange was softened up a bit from the cast manifold change where the tubular woke the car up top.

Turbocharged Z3 M Coupé

“The next update came a few years later in 2009 when the turbo was swapped to an FP GT3586R HTA one and with Nick again performing some tune upgrades in person at ICS Performance in Connecticut we were at a respectable 537whp/496lb ft wtq. The torque hit had returned with a good shift of the curve to the left, but something was still holding back the car, it was still not gaining what was expected of these changes,” says Ken. “Then, in 2010, the ‘Ah-ha!’ moment happened when we realised that I had been chasing power without upgrading the obvious – the intercooler! The original Technique Tuning intercooler was holding us back as it was too small for this application. Gerhard at Bell Intercooler was contacted to get his thoughts and come up with something specific for the car. The intercooler was what was needed to take the car to the next level and with the custom item on board, the car definitely felt faster but I wouldn’t have numbers until 2011.

“Nick was coming back to Maximum PSI for a custom tuning session and it was time to see some results but not on a Dynojet yet, a SuperFlow unit would be telling us the story this time. Now, these read lower than Dynojets, but the car still made more power than before, we were up to 550whp on 93 pump gas at 20 psi,” he grins. “One minor change at this point lingered, and that was on the intake side. The 3” was updated to a 3.5” with an ITG Foam filter, and we relocated the reference for WG to after the intercooler rather than from the compressor housing so there was less boost taper. The next runs were 560whp! Now we needed comparable Dynojet numbers. The final result: 603whp and 539lb ft wtq at a peak boost reading of 20.5 psi. Most recently with a 2.93 differential change and a little of Boostane added for octane safety, on 93 pump gas the car made a best of 620.64whp and 554.37lb ft wtq at 21 psi,” he smiles triumphantly and those are some serious numbers, around 700hp at the engine, and that means this Z3 is an absolute monster. The gearbox, meanwhile, has been upgraded to help it cope with these massive numbers and the stock ZF five-speeder is mated to a Spec six-puck Stage 5 clutch and sends power to the wheels via a RacingDiffs 2.93 ratio four-clutch LSD.

With this much turbocharged power on tap, Ken has not forgotten about the chassis and while things started with aesthetics in mind, the upgrades evolved to comprehensively enhance the car’s handling capabilities. “It started with suspension for the car to sit perfectly how I wanted; modified PSS9s are fitted all-round,” says Ken. “The car also has a custom subframe reinforcement by Don Fields at Mr. M Car; it was the first vehicle he completed the modification on and was a bit more beefed up than any other he carried out afterwards as well. This was done in advance of the turbo setup, prepping for the inevitable knowing a significant power bump was coming in due time,” he says and pre-emptive upgrades are a very sensible move on a build of this scale. “Porsche 996 calipers powder coated Stryker Orange have been fitted using RallyRoad conversion brackets along with E46 M3 discs and ceramic pads. A front strut bar by Mason Engineering has also been added, also powder coated wrinkle black like all of the other piping and visible pieces in the engine bay,” says Ken and that rounds off a comprehensive selection of chassis upgrades that ensure this Z3 can handle all of its 620whp with ease.

A large part of the Z3’s appeal without a doubt lies in its unconventional looks and so when it came to styling, Ken’s approach was very much one of less is more. “I did not want to take anything away from the aesthetic of this car but only slightly enhance it,” he says. “There are not many options for the M Coupé out there as far as body design is concerned, but the few items were simply to improve the look at a very minimal level. A Never Done Design House rear diffuser is out back along with a deleted rear wiper, it also has some LeatherZ stone guards, an ACS rear wing with custom carbon fibre centre section and custom-built bi-xenon headlights by Skylar Graham. The simple and subtle additions essentially completed the exterior in my eyes,” he says and we have to agree as they only serve to enhance the M Coupé’s muscular and iconic styling and that’s just perfect.

Turbocharged Z3 M Coupé

The drop served up by the Bilstein PSS9s further assists on the aesthetic front as do the wheels, and Ken’s choice suits the car perfectly. “I was never one for flashy wheels, even the whole car isn’t meant to be flashy but rather subtle and generally stock-looking. An M Coupé gets enough attention as it is,” he grins. “When the stock Roadstars simply weren’t enough, basically in regards to width in the rear, I started looking around. Apex Race Parts makes an extremely lightweight and high-performing, track-tested and certified wheel for a great price point; they also have great big brake clearance in only a 17, which is a size I wanted to retain at the time,” he says and the ARC-8s he’s chosen look fantastic. They measure 8”-wide up front and 10.5” at the rear and Ken has added a set of 18mm spacers to make sure those fat rear arches are properly filled out.

In terms of interior, the turbocharged Z3 M Coupé was blessed with a vibrant two-tone cabin from the factory and, as with the exterior, Ken has kept things largely standard but there are a few additions that make all the difference. “One item I did focus on was the steering wheel; the stock wheel leaves much to be desired, it’s far too thin and just doesn’t feel right. I originally wanted a Raid wheel, but they are now NLA and impossible to find. I then went through the idea of swapping in a Z4 M wheel like others have done as I loved that wheel on my prior M Roadster. I was about to do the swap when I found a company called AZA Auto doing some quality work and saw results on a few cars on social media platforms. So I had a wheel created that wasn’t like another done by them on this style at the time, with carbon fibre and two different leather styles. This started what will be my orange secondary colour theme going forward,” he says and the custom wheel looks awesome with its sculpted grips, carbon elements and orange stitching plus orange centre stripe. There’s also an extremely sexy custom-engraved Doug Whalen gear knob and a dual gauge pod housing an AEM wideband and AutoMeter electronic boost gauge, plus some upgraded audio to finish off the interior mods.

Ken has been working on his turbocharged Z3 M Coupé for around eight years so it’s not surprising that it’s such an awesome and impressive machine and he has created a truly epic M car that impresses on every level. While it has been in modding hibernation for around six or seven years Ken is far from finished; “It’s always evolving, I don’t think you are ever truly finished with a build – a better ‘something’ always comes out that you can upgrade or change to. Over the winter a bump to 80lb injectors, some Schrick cams and hopefully a 100+ octane tune will let us see how close to 700whp – or even beyond – we can get! Furthermore, an E46 Getrag 420G six-speed gearbox and custom single-piece propshaft are going in the car to handle the power much better than the current drivetrain. Very recently I also stumbled upon and almost purchased my dream wheels that I have been looking for years, a properly fitting rare set of BBS LMs, which have now been completely refinished and will be on the car in the spring. A full restitched interior with a custom half-cage and some type of Recaro or similar seats are also planned to happen soon for safety purposes,” says Ken and it sounds like he’s going to have his hands full with this Z3 M for quite some time to come and there’s really no rush because this car is going nowhere. “I really don’t think anything will replace the M Coupé for me, it’s just too special,” he says with a smile and, standing back and taking in everything about this epic machine, we totally get that.

Turbocharged Z3 M Coupé

Tech Spec: Turbocharged Z3 M Coupé

Engine & Transmission:

3.2-litre straight-six S52B32, fully rebuilt with all-new bearings, gaskets, bolts etc., CP 8.5:1 pistons, Arrow rods, ARP bearing, main and head studs, CES cut ring head gasket, M50 intake manifold, 3.5” intake with ITG JC60 filter, Forced Performance HTA3586 ATP 0.82 T4 turbo, ceramic-coated 3” V-band housing, tubular exhaust manifold with 3” downpipe, centre Magnaflow silencer, dual 2.5” Vibrant exhaust system, Ferrea valve spring set, DrVanos full kit, mild head porting and polishing, custom Bell intercooler, Driven Innovations fuel rail, Aeromotive FPR and gauge, modified push/pull Spal fan, S54 oil housing and Setrab oil cooler, S54 radiator, E36 power steering Loop, Tial V44 wastegate, Forge BOV, Aquamist HFS-3 water/methanol injection. ZF Type C five-speed manual gearbox, Spec six-puck Stage 5 clutch, Racing Diffs 2.93 four-clutch diff, Garagistic diff studs

Power & Torque:

620whp and 554lb ft wtq


8×17” ET20 (front) and 10.5×17” ET27 (rear) Apex ARC-8 wheels with 245/45 (front) and 275/40 (rear) Toyo R888R tyres, 18mm Rogue Engineering spacers (rear), Apex stud kit, Bilstein PSS9 suspension, RallyRoad engine mounts, Mason Engineering Race strut brace, Racelogic traction control, Porsche 996 calipers custom-painted Stryker Orange with E46 M3 discs and ceramic pads (front and rear), RallyRoad conversion brackets and stainless brake lines, custom converted E46 handbrake setup


Custom-modified bi-xenon headlights by Skylar Graham, Estoril blue-painted kidney grilles and side vents, LeatherZ magnetic stone guards, AC Schnitzer rear spoiler painted Estoril blue with custom carbon fibre centre section, Never Done Design House rear diffuser, rear wiper delete, mini antenna


AZA Auto custom flat-bottom steering wheel with perforated and smooth leather sections, carbon fibre top section, orange centre stripe and stitching, HMS harness bar, dual gauge pod with AEM wideband and AutoMeter electronic boost gauge, Aquamist meth gauge, AMS-500 boost controller, custom-engraved Doug Whalen gear knob, Joying head unit, custom Mister X subwoofer box with Kicker CVR 10”, Alpine PDX amps, Focal polykevlar front & rear components