Porsche 718 RSK replica

2018 Charlie Magee & Drive-My

Porsche RSK Recreated Perfect clone of a perfect sports car. Body Double When 3D scanning was in its infancy, an engineer set out to create the most accurate ever Porsche 718 RSK replica. After a decade of blood, sweat and tears, this is the result. Words James Elliott. Photography Charlie Magee.


HOMEBUILT PORSCHE RSK


Not all replicas are born equal. It wasn’t so long ago that the lexicon was rather more straightforward: a road car was real or it was a replica. Nowadays, thanks to the determination to differentiate between the various castes of replicas, to elevate some above others or just to hype up a car for sale, we have a Roget-baffling range of descriptions: from recreation and homage, via reimagining and all the way up to the usually lamentably misused ‘tool-room copy. All mere garnish to Jenks’ original categories of resurrection, reconstruction, facsimile et al, of course. Almost as confusing is the social acceptability of replicas – whether scratchbuilt or involving the ritual sacrifice of a less desirable model – even beyond the throngs who refuse to countenance them at all.


Porsche 718 RSK replica

Porsche 718 RSK replica road and track test drive

I am fascinated by them simply because I admire engineering and craftsmanship almost as much as any other aspect of motoring, and to see something built in the modern day to look precisely as it did in period, especially if it uses the same methods, can be mesmerising. Lynx Jags are terrific, but even better is something done by one man, allowing you to draw a timeline straight back to the men-in-sheds of the 1950s. And the icing on the cake comes when that artisan genius, with a background in building hotrod Beetles and outlaws, creates a six-figure car as perfect as this.

Take a bow, Paul Foreman.

This electrical engineer from Rochester started with ’bikes and is still into them, but then became obsessed with air-cooled VWs – owning, building and modifying Campers, Beetles, beach buggies and Baja Bugs – before following the seemingly almost natural progression to 1950s Porsches. He started with 356 reps – and will return to them for his next project, an outlaw 356 – and then a 550 Spyder, but, though he modified the chassis, these were the usual glassfibre fare. For his next project he wanted to do his ultimate Porsche, the RSK RS60/61, and he wanted to do it in metal. ‘I’ve always liked the shape best and I thought it would be more of a challenge,’ he says. ‘I think it has a better look than the 550, which is readily available off-the-shelf in kit form. There were a few companies that made what I would call a “likeness” to them, but nowhere near correct enough for me.’

It’s difficult to counter his thinking; thanks to the cult of James Dean and his premature end in his 550 Spyder, the RSK has been totally overshadowed by its predecessor, which also shared some 356 architecture. With its 1500cc four-cam rear/mid-mounted, the 550A had an all-aluminium body over a spaceframe chassis (unlike the earlier ladder-frame 550) and was curvaceous enough still to bear a resemblance to the car it was based on. Glory came in the form of an overall win on the 1956 Targa Florio but, the following year, the 550A gave way to the 718.

The RSK moniker came from RennSport Kurz and, similarly powered by the Type 547 Boxer, it had enormous success in competition. The 718 RSK was followed by the 718 RS60, which simply meant that it was for 1960 with a 160bhp 1600cc variant of the engine that propelled it to victory in Sebring and Sicily.

Differences for the 14 or so RS61s were minimal, mainly to do with changing of the rear lights, but more radical change was called for with the W-RS, GTR Coupé and single-seater variants. But then, why would you mess with the RS60’s shape unless you had to? Gone is the cutesy upright-light friendly appearance of the 550 and in its place is a delicately aggressive outline of beautifully balanced curves.

It was the curiously bulbous (seeing as there isn’t an inch of fat on it) shape that most inspired Foreman. This silver arrowhead (in profile) has wonderful stance and captures a perfect moment in the Porsche design idiom before you see the 904’s lines start to emerge in the W-RS. Perhaps the appeal is that the details so clearly betray that this is from the Ferrari school of thought that a racing car can be beautiful as well as functional. And symmetrical, too. So much thought has gone into incorporating and absorbing practical elements such as the driving lights, gilled flank and rear grille, like multiple focal points in a single artwork.

As mentioned, there are already replicas out there, so you have to understand a little more about Paul Foreman to know why he decided to build his own car from scratch rather than just build or adapt an existing replica. ‘It all started at the Le Mans Classic in 2006. I saw the original car racing there and it had a UK registration, so I tracked down the owner and told him I wanted to do a 3D scan of it and would share the data with him so that if he ever damaged it he could put it back to exactly how it was. He was happy to do that: he’s owned replica cars himself so he wasn’t snobby about it at all.’

The scanning was done by Central Scanning in October of that year, when such technology was still in its infancy. That still left Foreman plenty to do and he was a regular sight in race paddocks, taking more measurements or photos to make sure that his car was spot-on. He explains: ‘I came to Goodwood one year when there were a couple of them here and I brought a dressmaker’s tape measure with me to measure the distances between the bottom of the dash and the floor and suchlike because they were details that I didn’t have. People used to look at me weirdly, thinking “Why is he taking a picture from underneath the dash?”, but I wanted to see what the dash looked like from the unseen side because that’s an image that no-one will ever have taken and I needed to know how it would have been done at the factory to get it right.’

After the 3D scanning, the scans were printed out full-size, allowing Foreman to lay them over MDF and cut out the correct shapes to 0.1mm accuracy. Like doing a jigsaw puzzle, he then built the panels into a wooden buck upon which a friend hand-formed an all-aluminium body, mostly 1.5mm thick, but with a bit of added weight in some sensitive areas such as the nose to make it a little more ‘sturdy’. During the two years the body was being painstakingly built with a mixture of welding and riveting identical to the originals, Foreman started work on building the chassis.

First he had to build the jig and then he could start on the tube-work: ‘I built my own chassis, which I made having taken all the dimensions off the original. It’s a seamless steel round tubular chassis that I fabricated out of 10-gauge (about 3mm thick, roughly twice that of the originals, but I could still pick it up and walk around with it). I wanted it to be as correct to look at as possible, so from inside the car it is identical to original but, because I am not using the four-cam engine and gearbox, the mounts are different.’

Instead of the infamously peaky four-cam (its power coming in between 3000 and 3500rpm), Foreman opted for the more practical, available and affordable 914 engine and transmission: still a horizontally opposed air-cooled Porsche unit fed by Dellorto DRLA 40s, but after fettling and flowing – capacity enlarged to 2.1 litres, high-lift cams and a dry sump – it offers 130bhp. The engine was mated with the 914 dogleg box, like an early 911’s except turned around and with the diff flipped. The suspension was slightly more complicated because some of the original components simply aren’t available. Faced with the option of having to bodge it, Foreman instead opted for a completely different set-up, as he explains: ‘I had to make my own uprights for the rear and wishbones. The front suspension I designed from scratch. The original cars had torsion bars, but I had a picture of an original car that had been modified to have wishbones at the front. Because it was something that had been done to a period car, I decided to go for a wishbone front, so now I have coil-over-shocks and wishbones all-round.’ Plus anti-roll bars front and rear. The worm-and-gear steering box made way for a rack-and-pinion system with 2.4 turns lock-to-lock, and all four brakes are discs but with covers that go over to make them look like drums from the outside.

With a full tank of fuel the whole package weighs a meagre 640kg. That’s still a small person heavier than an original, but the girth saving from the far lighter front suspension is outweighed by the thicker chassis and heavier engine. Still, its creator was happy: ‘I would hate to think how many hours went into it. It was a labour of love, really. When you do a car like this from scratch without any plans there’s a lot of working out how things fit and that is time-consuming. As much time was spent thinking as doing. And fabricating things from scratch. Plus there were things I had to change once I had started building it, like the front suspension. I wasn’t happy with the geometry so I started again.’

Even after listing the modifications, from the driver’s seat on a damp Goodwood Circuit you couldn’t be anywhere else but a real RSK. Visually it is incredible. A lot of the parts are 356 because that was what they used at the factory, though you can spot that some items, such as the door catches, have been beautifully handcrafted.

Fire it up and there is a noise-meter-rattling bellow from the stainless steel straight-through exhaust. With a single-exit pipe, it’s four-into-one and glorious. The clutch is light and just 1500-2000rpm gets it off the mark, though it will rev up to a screaming 7000rpm. The transmission is the later 914 type with a sideshift, which is more positive because there’s less linkage to go through. All of which, along with huge torque and that rack offering direct inputs and fulsome feedback via the VDM replica steering wheel, makes this car extremely exciting but also extremely easy to drive. The lack of a screen or weather gear as Sussex is soaked from above is rather less endearing. The downpour also reveals the flipside of this car’s character: in the dry it handles beautifully, but simply because of its power-to-weight ratio it demands big respect in the wet. Even riding on Blockley radials it is very easy to get out of shape.

But that is the exception; in normal circumstances and normal weather it is only the cacophony tumbling from the exhaust that makes this car unsociable.

It’s actually very comfortable on the road because it’s quite softly sprung: 250lb at the front and 275lb at the back, with adjustable dampers. It could do with being harder in the track, but that would detract from its road manners. However, with the set-up Foreman has used, it should be a doddle to change the ride and handling characteristics.

With my driving done, but my ears still ringing, Foreman confesses he did only about 400 shakedown miles in the car before he sold it. In fact he had known early on in the project that would be the outcome: ‘I borrowed the money to do it from my parents and they needed to be paid back. The only way to do that would be to sell it, but I wanted to do it anyway. It’s a passion and I get a lot of pride when people can see the work that has gone into it and appreciate it.’

There is a happy ending, though. ‘I told the owner of the original I’d make only one, but I really want a keeper for myself and he’s said OK. It should be much quicker, easier and cheaper second time around and it will be pretty much identical to this, but I might do it in Porsche Royal Blue. I’ve got the engine (which will be a bit bigger), the drivetrain, the chassis and the gauges. It’s just a case of getting the body made and assembling it. Hopefully it will be done in a year…’


THANKS TO Adrian Crawford of Williams Crawford, www.williamscrawford.co.uk.


‘JUST AS MUCH TIME WAS SPENT THINKING AS IT WAS DOING… AND FABRICATING THINGS FROM SCRATCH’

Right 3D scanning was new technology when Paul Foreman started work on this car more than ten years ago. Clockwise from above Skittish in the wet – as per the original; details are immaculate throughout; 914-based flat-four provides plenty of power; Foreman talks Drive-My through the build. Clockwise from left From the driver’s seat it’s exactly like the real thing; big decibels on the move; handformed buck was created especially for build.

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Additional Info
  • Year: 1958-2018
  • Engine: Petrol B4 2.1-litre
  • Power: 160bhp at 6800rpm
  • Torque: 109lb ft at 4800rpm

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