360bhp RSR-inspired 1986 Porsche 911 Turbo 930 Restomod

Complete with TracTive suspension, a G50 gearbox and 360bhp on tap, this stunningRSR-styled 911 Turbo has the ‘go’ to match the ‘show’...

Words Steve Bennett

Photography Oliver Brookwell

GREEN PARTY

An RSR-inspired 1986 Porsche 911 Turbo 930 Restomod

We’ve all been there. You nip out to buy a 997 GT3 and you come home with a Chartreuse-finished RSR-lookalike 911 Turbo (930). Months of market research, stalking, test driving and patient anticipation in search of one of Porsche’s finest GT road racers, all wiped out on a whim. A classic case of heart ruling head? Maybe love at first sight?!

Of course, such emotion doesn’t always end well, particularly when the attraction is only skin deep. In this instance, however, we can lend support to Steve Miller’s impulse buy. In fact, we have history with this particular 930 — back in 2018, it deservedly featured on the cover of our sister title, 911 & Porsche World. “One of the finest hot-rod builds we’ve had the pleasure to experience,” was our conclusion.

That’s quite the accolade, given the number of 911 restomods, retro-builds and hot rods we’ve sampled over the years. And we include output from Singer Vehicle Design, Paul Stephens and other high-end werks among them. What was it that so impressed us with the green machine? Well, like Steve, we were initially struck by its RSR-aping look, but more than this, it was the quality of the build. Specifically, the bodywork, engineering and overall specification. Oh, and the small matter of it being based on a 930, which is a pretty ballsy choice of donor and somewhat leftfield when compared to the usual G-Series 911s used as the starting points for projects like this.

As difficult as it is for us to believe, the aforementioned magazine feature was published five years ago. It is therefore appropriate for a quick rewind. The story starts with another Miller: Jon (no relation), main man at Limerick-based air-cooled Porsche restoration specialist, Classic Carreras. For him, the story winds back even further to 2012, when he was looking for a suitable project to showcase his company’s extensive capabilities.

He spotted the car on eBay. A 1986 example in black, it carried what the seller believed to be a blown turbocharger. Scruffy bodywork suggested a world of pain could be hidden within, but Jon wasn’t deterred — a cheeky bid secured ownership. And, with the car in the Classic Carreras workshop, there was good news, insofar as turbocharger failure turned out to be nothing more than a blown seal. Beyond this, however, the bodywork was every bit as bad as Jon suspected. Possibly worse, not that his team were phased by the kind of corrosion they face on a day-to-day basis. They run a classic Porsche restoration business, after all.

The shell was rotten in all the usual places. Indeed, the bottoms of the B-pillars, the sills and the kidney bowls were in need of attention, the latter virtually non-existent. With the car stripped and fixed to a jig, the process of repair involved a mix of OEM Porsche and aftermarket Dansk body panels. Working with a 930 made the decision to create an RSR evocation something of a nobrainer — the 911 Turbo features a wide body to start with, although Turbo arches aren’t the same as those of the iconic RSR.

As a promotional build for his company, Jon was adamant there could be no short-cuts during the project. Consequently, correct RSR steel flares were ordered from historic Porsche parts supplier, Ben Coles. Modification of the stock panels commenced. It took much in the way of tweakery to get the wings to align correctly with RSR front and rear bumper mouldings, and for the wheels to sit exactly central in the arches, but this is all part of the Classic Carreras skillset.

Important as it was to get the look spot-on, this wasn’t to be a slavish RSR copy, not with a 911 Turbo engine in the back. For this reason, Jon decided to run the oil lines internally through the sills, thereby tidying the exterior. Adapting the G-series frontend for the early long bonnet look is straightforward enough, but he also wanted fit a fully functional oil cooler in the front valance, which involved cutting into the bulkhead and fabricating a duct to channel air under the car after passing through the cooler’s fins.

Expertly planned, the build introduced changes requiring further bodywork modification before the shell could be painted. Torsion bars, for example, were ditched in favour of fully adjustable coilovers. A must for handling nirvana, but it does put more strain on the bodywork, especially the upper rear shock mounts, which is why Jon strengthened the shock towers at the front of the engine bay.

At this point, he also had to make a fairly major decision regarding his choice of transmission. As any 930 student will tell you, a 1986 911 Turbo comes equipped with the robust, but somewhat slow-shifting Type 915 gearbox, complete with only four ratios. Jon was determined his RSR-styled Porsche would make use of the much-improved Getrag G50 five-speed cog swapper. The problem with this idea, however, is that the G50 won’t fit into a 1986 930 shell — the torsion tube gets in the way of what is a longer transmission housing. Granted, shifting to coilovers was going to make the torsion tube redundant, but Jon rather preferred the more radical engineering solution of shortening the G50 bellhousing by the required twenty-nine millimetres, as well as shortening the input shaft. And while he and his team do most of their work in-house, the machining was entrusted to Mike Bainbridge at MB Porsche Engineering in Kendal. Mike also installed a Quaife ATB limited-slip differential, plus a taller fifth gear from a 1989 930 gearbox, ensuring Jon could take full advantage of his modified Turbo’s cruising potential.

The car’s defining ‘ducktail’ looks the part, but has been subtly altered to accommodate the Turbo’s sizeable intercooler, which sits horizontally across the top-left side of the engine. An extra slot has been cut into the lid in order to allow for welcome extra airflow.

Is there a better colour than Chartreuse for this 911? Jon is to be commended for his choice. Likewise for the inspired purchase of Group 4 Wheels PAG Campagnolo replica rims, which are a full-fat 8x15 inches at the front and 10x15 inches at the rear. When first fitted, these ‘Pags’ were painted black with polished silver rim and spokes. Steve has changed the finish to the more traditional — and, dare we say it, better-looking — gold. Michelin TB15 cut slicks are perfectly period correct. Other finishing touches? The door and window trims were given a polished finish, while super-rare Hella 4004 GT door mirrors add an extra esoteric element.

Aesthetics out of the way (for the time being), there’s much to cover on the chassis and drivetrain of this ground-up rebuild. Being a 930 meant there was little point in deviating from the 917-inspired brakes, which were subject to a full rebuild. The coilover conversion kit came courtesy of US-based Rebel Racing. Jon chose to raise the stub axles on the front struts to lower the car without unduly affecting geometry. Taking the original parts, he ground-out the welds holding the stub axle forgings to the strut bodies and re-welded them nineteen millimetres higher up. He then welded-in the lower perch for the for the coilover conversion and added gussets to give extra strength, along with Weltmeister anti-roll bars and a bump-steer kit from Elephant Racing.

At the rear, the original aluminium trailing arms were vapour blasted. All ancillary components, such as brake backing plates, caliper mounts and hub assemblies were either powdercoated in black or plated. With much of the original Turbo wiring loom redundant, Jon fashioned a new one based on simpler 911 SC wiring. Substituting the original Turbo fuse box is a modern equivalent from Classic Retrofit, complete with blade fuses and relays for the headlight circuits. A programmable CDI ignition unit has also been added.

The force-fed flat-six may not have been supporting a blown turbocharger, but it was absolutely ripe for a rebuild, which was carried out in-house at Classic Carreras. The standard 3.3-litre internals were retained, while a K27/19 hybrid turbocharger and TiAL wastegate replaced the standard spinner. Boost is set at 1bar. SC cams, a lightweight flywheel, equal-length headers and a custom exhaust completes a powerplant producing a healthy 360bhp, which is ample.

The factory-optioned deep red leather Sports pews are long gone, replaced by a pair of Recaro Rallye III buckets, the final incarnation of this classic seat, first introduced in 1967. Interior trim is crucial to the restomod process — Jon opted for a fabulous lime green plaid, originally specified for the 914 and perfectly complementing the Chartreuse paintwork.

The dash top was modified for the early centrespeaker look, complete with the correct perforated finish. Dials are standard 911 Turbo fayre, but with earlier ‘silver dot’ speedo and rev counter needles. Carpets are salt-and-pepper. The lightweight door cards feature a pull strap to open. Embossed leather door check straps feature the Porsche script logo.

The interior’s biggest statement, though, is the gear shifter, which is a combination of Rennline lever and drilled billet gearknob installed on a Rebel Racing raised tunnel shift tower, which lifts the shifter, bringing it much closer to hand and adding extra precision to proceedings. Plus, it looks very cool indeed.

So, then. That’s the Classic Carreras build. Jon enjoyed the car, and it certainly served its purpose as a rolling promotional tool for his business, but other projects took over and, when we encountered the green machine in 2018, it was at Devonian Porsche emporium, Williams Crawford, where it was in the process of being sold to a Porsche collector. Further time passed, the pandemic hit and, when the height of the crisis was over, the car had washed up at Oxfordshire-located independent Porsche sales and maintenance outfit, Maundrell & Co., which is where we met Steve.

Steve races Porsches. He cut his teeth in 924s and is currently racing a 996 in the Classic Sports Car Club’s Modern Classics series, where he is paired with wellknown Porsche Experience Centre instructor, Dave Hornsey. Maundrell’s had just the 997 GT3 Steve was looking for, but never underestimate the strong pull of an RSR-look 911. Resistance was futile, buoyed by his close relationship with the team at Maundrell’s. “I drove it, loved it, but realised the car was in need of tidying following time it had spent on the road since the restoration.

This was a good thing, because it gave me the opportunity to put my stamp on what would otherwise have been a finished build.” Maundrell’s assigned star technician, Craig Mayo, to look after the car. As a Porsche-trained and accredited Carrera GT technician, it’s safe to say he knows his stuff. There was also a sentimental reason for Steve’s decision to buy the car. “I lost my best friend, Andy, a few years ago,” he reveals. “He was just forty-five years old. We used to go mountain biking together and shared a love of cars. He owned a green 911 Turbo. I have so many fond memories of us in that car. My 911 is therefore symbolic of my love for the times Andy and I spent together.”

Being a racer at heart, Steve’s first instinct was to get the chassis set-up absolutely spot on. Little surprise, then, he took his new toy to Center Gravity for corner weighting and a full geometry workout. “I quizzed company founder, Chris Franklin, on his advice for the ultimate suspension makeover. He recommended a TracTive active solution.” We wouldn’t disagree. Moreover, Chris has an extensive database of damper and spring settings to get most conversions quickly to the point of fine tuning.

TracTive’s Active Controlled Electronics (ACE) dampers are fitted with patented Dynamic Damping Adjustment (DDA), a dynamic proportional valve operating as a bypass, allowing capacity for an unusually large range of damping. Capable of operating from soft to hard in a barely believable six milliseconds, a TracTive ACE system is one of the fastest aftermarket suspension solutions available.

ACE has an intuitive ability to react to changing track surfaces and road conditions. Bumps compressions and rumble strips mid-corner will be absorbed before the driver has time to react, easily holding the desired line through a series of high-speed corners, without being thrown offline. Grip levels in all conditions are vastly increased, giving the ability to push the host Porsche to limits the driver previously thought not possible. Configuration can be achieved by way of a rotary switch or touchscreen controller, allowing damping presets to be stored and activated in an instant, even when on the move. Steve opted for the nifty touchscreen, which is positioned beneath his 911’s heater controls.

The challenge, of course, is to develop a range of settings perfect for driving on British roads. We’ll get to the driving experience shortly, suffice to say, we’ve driven a high number of TracTive-equipped 911s, allowing us to claim (with some authority) the company’s product line as being a game changer.

Something noted back in our 2018 test was obstructive gear change, which Steve immediately picked up on. “It’s transformed,” he says. “Craig has worked his magic and shifting is now perfect.” Similarly, the throttle cable was snagging, but now operates as it should. “Small jobs,” says Steve, “but transformative to the driving experience. All typical stuff for an air-cooled 911 not driven for a while, mind.”

He plans to use the car for long journeys, which is why he’s injected a bit of comfort. The suspension, for instance, utilises Powerflex polybushes in place of the largely solid set-up Jon installed. Steve has also added sound-deadening material to the bodyshell, which seems entirely reasonable. This is a road car, after all, and while stripped-out and buzzy is invigorating for a short dash, it becomes bloody annoying half-way to Le Mans. The engine has been left well alone. It’s plenty powerful enough in what is essentially a lightweight classic 911. “It’s fast, but at the same time, very drivable.” Time to find out.

There are 911 hot rods you instinctively know will be good — the combination of Jon’s original build, Steve’s finishing touches and the transformative TracTive makeover bode well. And so it proves, but what makes a really good 911, whether standard or modified? One that you ultimately feel comfortable with, one that you can relax into, one that doesn’t fight back and one that works properly on a UK backroad. Steve’s RSR-styled Turbo achieves all of these things and more. Really, it’s one of the best we’ve driven. Again.

The turbocharged flat-six fires into life. The driving position is perfect, even for my long pins. The dished MOMO steering wheel is right where it should be. A gear lever that falls perfectly to hand is usually a case of lazy motoring journo talk, but it’s true — there’s no need for the time-honoured arm and shoulder stretch. The lever and gearknob are just a flick away and, as Steve puts it, operate like a knife through butter. The throttle is light, the clutch more than manageable. As a trio, the gearbox, clutch and throttle hold no vices, nothing to scare or provoke the horses, of which there are plenty. The rebuilt flat-six is super-responsive. The hybrid turbocharger spins up quickly, the TiAL wastegate quickly dumping excess boost and the lightweight flywheel adding to the zing. Perhaps the biggest influence on power delivery is the G50. Jon was right to insist on installing this unit. The 915, with its ultra-long ratios and moody shift, would have masked the engine’s new-found vitality. In contrast, the G50, with its closer cogs, makes the most of what’s on offer and adds a massive dollop of extra drivability. This 911 is fast, but at no point does the turbocharger kick in and suddenly overwhelm.

We should mention the brakes, too. With standard Porsche pads, they are seriously effective, to the point you have recalibrate the effort required. Another life lesson for a road car: you don’t always need a fancy race pad to come to a swift halt.

The final part of the jigsaw? The handling. The TracTive system brings twenty-first century suspension to a 911 which can trace its chassis back to the 1960s. Before we test it on the road, however, a word from Steve’s race partner, David, following a Ferrari track day at Castle Combe, where Steve’s 911 comprehensively destroyed the collected modern Italian stallions in less than perfect conditions.

“The 930 has always had a reputation of being a tricky car to master on the limit. It likes only to be driven one way and will punish drivers who make mistakes. Steve’s restomod, now with TracTive suspension, is an absolute revelation. I can categorically say this is the most composed, sure-footed, confidence-inspiring and compliant classic 911 I’ve ever had the pleasure of experiencing.”

The TracTive system creates and maintains a stable platform at all times. Nothing can truly overcome the pendulum effect of a flat-six hanging from the rear, but the active dampers will at least keep the mass stable and level, which makes a massive difference to overall balance. Add to this the way the chassis and suspension play out on these tough roads, smoothing out the surface, filtering out tyre roar, taking undulations and deep compressions in their stride.

Blown away? Yep, and why not?! This 911 hot rod pushes all the right buttons, most notably in the way it is perfectly in tune with UK roads and presents totally usable power over peak power. We’d need to wind forward to a far more modern 911 chassis, such as that of the 997-generation GT3, to come anywhere near close to the same quality, precision, feel, damping control, steering feedback, noise and flat-six scale. Kind of appropriate given that’s exactly what Steve went shopping for in the first place.

TRACTIVE BRINGS TWENTY-FIRST CENTURY SUSPENSION TO A 911 WHICH CAN TRACE ITS CHASSIS BACK TO THE 1960s

Above Steve went shopping for a 997 GT3 and ended up with this gorgeous green 930. Right TracTive dampers are controlled by way of digital touchscreen calling up five different configurable presets Below Classic Retrofit fuseboard adds extra reliability to this 911’s renewed electrics.

BEING A RACER AT HEART, STEVE’S FIRST INSTINCT WAS TO GET THE CHASSIS SET-UP ABSOLUTELY SPOT ON

Above Jon Miller spent a significant amount of time creating a perfect RSR-inspired wide-arch body.

THE FORCE-FED FLAT-SIX MAY NOT HAVE BEEN SUPPORTING A BLOWN TURBO, BUT IT WAS ABSOLUTELY RIPE FOR A REBUILD

Above Engine was fully rebuilt and now produces 360bhp from beneath a modified ducktail decklid, altered to accommodate the flat-six’s chunky intercoole.

Above 914 plaid fabric is a perfect match for the fruity Chartreuse paintwork Below Steve uses the car for long road trips, which is why he’s introduced additional comfort to the cabin and chassis, where solid suspension bushes have been replaced with polyurethane.

Above and below Based on a 1986 911 Turbo, Steve’s lean, green speed machine was built as a promotional vehicle (literally) for Classic Carreras.

THE RADICAL ENGINEERING SOLUTION OF SHORTENING THE G50 BELLHOUSING BY TWENTY-NINE MILLIMETRES