When Dan Dobson bought his dream M car, he thought it’d be enough for him in factory-standard form. But then a tuned BMW M4 showed him a clean pair of heels on the street, and the red mist descended… 

Feature from Performance BMW. Words: Dan Bevis. Photos: Jason Dodd.

If we had a quid for every feature car owner who told us that they never intended to modify their car, we’d be rolling a mightily impressive fleet of M cars. Most of the time, it’s little more than a fusion of historical precedent and FOMO that leads people to mod their motors; they may think it’s perfect as it is when they first acquire the vehicle in question, but it only takes a visit to a show or a scroll through Instagram to remind them of how much fun they had with their previous projects, and/or how cool other people on the scene are making similar cars. However, in the case of Dan Dobson (@dan.dobson), the impetus was a little more visceral: “When I bought my M4, my immediate thought was ‘I love it, I will never change it’,” he laughs. “But one day, when I was out driving about a week later, I challenged another M4 and he totally smoked me! At that point, things changed.”

He’s not kidding. What we’re seeing before us today is some way removed from a factory-stock M4. It’s been a long time coming for Dan too because while he’s always hankered after a full-fat M car, it’s only in recent years that he’s reached the life stage whereby he’s been able to afford one. But before this, he’d put in strong groundwork modding his other cars; his first, a more-door Focus 1.6, received a Powerflow exhaust; this was followed by a Type R Honda with a custom map (and any Honda owner will grimly tell you what a pain in the backside that is to achieve), a mapped Mercedes A-Class, and a mapped Audi TT quattro. Evidently, he well knows the benefits of cracking open a car’s brain and rearranging the furniture.

Tuned BMW M4

These kinds of shenanigans have been a lifelong enthusiasm too: “Right back as far as I can remember, I used to attend car shows with my dad,” he recalls. “I always thought the BMWs were special, as they can rival even the best supercars with the right setup – then at the press of a button, be sociable and quiet.” And when the time finally came to realise those lifelong dreams, there was only one model that would fit the bill: “The M4, I knew that was the one for me,” Dan beams. “The best-looking car with the best performance. Plus I knew I could tune it.” Aha, it’s all coming out now, isn’t it? There he is saying ‘I love it, I will never change it’, but that chance encounter with a quicker M4 didn’t exactly have a bunch of heavy lifting to do when it came to convincing Dan to open Pandora’s box.

“I found the car on Auto Trader, at a private appointment-only garage that specialised in performance cars,” he continues. “It had done 56k miles and looked in very good condition. And yes, within a week of that pasting by the other M4, I had mine up to Stage 1! Southern Coding installed the bootmod3 and gearbox software with upgraded air intake. Two weeks after that, I was stepping up to Stage 2…”

Tuned BMW M4

If he’s making it all sound too easy, let’s not forget that cars are naturally capricious things that like to fight back a bit, and taking the M4 into Hack Engineering for the makeover revealed that the stock turbos were leaking a little oil – a reasonably common issue with the S55 engine. Dan was asked whether he would prefer to replace them with stock items or upgraded hybrid turbos, and you can probably guess what his answer was. “From that point, things escalated,” he laughs. “I needed the brakes upgrading as the stock setup was failing badly and became dangerous with the extra power. Then the crank hub needed changing, and we needed meth to keep temps down. The list is endless!”

Yep, all part of the fun isn’t it? Mods follow mods follow mods, it’s an exponential process. Hack Engineering fitted the Littco L640 hybrid turbos, which boast bigger turbines, larger compressor wheels and stronger bearings for ultimate spooling prowess, and these were joined by freer-flowing cats and the eminently sensible crank hub capture plate. Before long, marque specialists Litchfield carried out the full crank hub fix, which involves replacing the whole assembly with an uprated item with oil pump drive pulley and cam drive pulley already installed.

Tuned BMW M4

The brake upgrade consisted of a raiding of EBC Brakes’ latest wares for the M4 platform, with floating front discs and fast-road pads joined by Hel braided lines; as soon as EBC release suitable discs for the rear, they’ll be going on too. And the water/meth injection? That’s a clever system that reduces inlet temperatures by up to 100°C, markedly increasing efficiency, eliminating detonation, and increasing peak power. Dan worked with Cooling Mist to optimise the setup for his car, starting out with a dual FTP charge-pipe arrangement, then upgrading to a three-way architecture with an extra nozzle in the J-pipe.

“After the meth, a custom tune was carried out by Cary Jordan of JordanTuned, who’s based in the USA and one of the best tuners in the world,” he says. “The oil cooler was changed around this time as the stock component failed, and Hex Code Tuning has also carried out loads of work for me, sorting the suspension and making sure the meth runs smoothly.”

With all of this focus on performance, though, Dan hasn’t ignored the aesthetics: “I started with the carbon fibre pretty early on,” he explains. “I was browsing through pictures of some track BMWs for new splitter and diffuser ideas, and when I came across the DTM M car I just thought it looked outstanding and I had to have it! This car is set up for track use but also occasional car meets, so I wanted it to look the part and back itself up with the speed and performance. The design itself has actually come from three different M cars – the bonnet from one, the roof from another and back of the car from an M2. The decals and sponsors you see dotted about, such as EBC and Littco, are the actual modifications on the car, so that’s a personal touch. The wrap was carried out by Monster Wraps, they did a great job.”

It certainly looks the part, and Dan was keen that this exterior attention to detail was carried through to the cabin as well; feeling that it was well-appointed but a little sombre for his tastes, he’s spruced it up by the addition of lots more carbon fibre trim along with some tasteful Alcantara – most notably the steering wheel. The interior’s an area that is still ongoing, in fact, as since our shoot he’s fitted a pair of lightweight bucket seats and six-point harnesses. Serious stuff, which has further inspired him to keep honing and refining the chassis. “At present, the only suspension mod is the Eibach springs,” Dan clarifies, “along with a proper road/track geometry setup. But I am debating coilovers, and some Millway Motorsport adjustable top mounts will definitely be finding their way in.”

Tuned BMW M4

Wheels are also on the to-do list, as is so often the case with ongoing projects. “I started out with the stock 437M alloys,” he says. “I did like them as you could see my brake upgrade well – I’m a fan of seeing the discs and calipers! However, I soon changed to the 666M-style alloys you see here, as I just thought the design was stunning.” Since the shoot, these have been swapped again for CS-style wheels, which are lighter and give an even better viewing window for the brakes. And who knows what he’ll be swapping on next? Something to get bystanders gawping at his stoppers, that’s for sure. “The EBC brakes are my favourite upgrade on the whole car,” Dan enthuses. “They look stunning, and the performance is fantastic. The stock setup just didn’t handle the power – that’s not down to BMW failing, merely that the extra power demanded a better solution.”

The way Dan talks about the tuned BMW M4 today, it’s all a very long way removed from that initial assessment that ‘I will never change it’. He’s a man converted; indeed, a man possessed. Possibly he didn’t see things going this far, but there’s no point putting your hands up to try to stop an avalanche. “I never expected it to be this tuned,” he says. “It was mainly down to those leaking turbos – after that point, we had to upgrade the whole car due to the power increase, and it snowballed. And really, I can’t deal with other M cars beating me – it’s the competitiveness in me.” And there you have it. Much like the M division itself, Dan just can’t help pushing for perfection. This definitely isn’t the last we’ll be seeing of this ever-evolving M4.

Tuned BMW M4

Tech Spec: Tuned BMW M4

Engine & Transmission:

3.0-litre twin-turbo straight-six S55B30, Littco L640 hybrid turbos, Modstock single mid-pipe exhaust system, Injen induction kit, Mishimoto oil cooler, Litchfield crank hub fix, FTP charge pipes, Cooling Mist triple-nozzle Stage 2 meth kit with stealth tank, Burger Motorsports oil catch can with billet cap and filter, custom tune by Cary Jordan (JordanTuned). Seven-speed M DCT gearbox


610hp (525whp)


19” 666M-style wheels with 255/35 (front) and 275/35 (rear) tyres, Eibach springs, EBC floating front discs, EBC pads, Hel braided lines


OEM Mineral white paint, custom wrap, carbon fibre front splitter, grilles, canards, mirrors, side blades, rear diffuser and wing


Alcantara steering wheel with red stripe and red M buttons, carbon fibre shift paddles, carbon interior trim, stealth meth tank in boot