Thornley Kelham European SL | UK Review

Why the last rear-engined Porsche to be restomodded might be the most charming...

By Matt Bird / Saturday, 24 October 2026 / Loading comments

Given its significance as the first production Porsche, it seems surprising that there hasn’t been a 356 like Thornley Kelham’s European SL before now. We’ve seen 912s, 914s and, of course, an abundance of modified 911s, but nothing quite like this. Well, over here, at least: Rod Emory has been doing his thing in California for 30 years. Probably quite a few of the 50 SLs will end up there. But as re-imagination projects go, a UK-based company taking on a 356 feels significant.

And better late than not at all. The 356 of course has a long and illustrious history when it comes to modifying, going all the way back to 1954 and the suggestion of Max Hoffman (Porsche importer at the time) to make one with a chopped windscreen and less equipment to appeal to West Coast hot rodders. Thus the Speedster was born. Thousands were sold, Porsche would resurrect the nameplate numerous times for the 911, and it became clear that the appetite was there for lighter, sexier, faster sports cars for those who really wanted to drive. The 356 was always going to be taken on again at some point, but with fewer of them than 911s - as well as a less evocative engine in its bum - it’s always been pushed down the queue. Even Thornley Kelham themselves did a six-cylinder Porsche first.

The SL story goes back even further than ‘54, as this creation pays homage to the Super Leicht Le Mans class winner of 1951. The 75th anniversary of the result, just a few years after the company’s formation, seems as good a milestone as any. Especially given what Porsche would go on to achieve in endurance racing.

As with the XK project, what Thornley Kelham has created here is a fascinating amalgamation of retro sports car, old school hot rod, contemporary road racer and, to be frank, hand-crafted automotive sculpture. While the ride height and track width make it immediately clear the SL isn’t the average 356 celebration, it’s the details that really take it to the next level: the windscreen is less upright (there’s new glass throughout), the teardrop silhouette tapers more dramatically, and the strakes give off just the right sort of Carrera Panamericana vibe.

The SL feels both innovative and authentic, which is a neat trick for a fresh design to create all these years later; true to its roots while also being beautifully rejuvenated and reworked. Thousands of hours very well spent, basically, using modern methods to make a very cool classic. As Chief Design Gary Ragle puts it: “The European SL is instantly recognisable as a Porsche 356, yet possesses a level of refinement and impact on the road that is rarely seen.” There’ll be no mistaking it for a standard car in any scenario. First job jobbed for a million-dollar restomod, then.

‘Exemplary’ is the word used by TK to describe comfort levels of this sub-tonne Porsche - you wouldn’t be alone in thinking of a few other words instead. But it really is a lovely little thing to sit in, with ample room for a driver who would have qualified as circus-spec in 1951. It’s almost a shame to sit in the seats, as that means no longer looking at a perfect pair of retro buckets. But it does at least afford you a better view of the dash, with a row of beautiful Bakelite-style switches and very cool dials behind the flying saucer steering wheel. Once more this feels like how you’d imagine a 356 to be, but in reality it’s much improved: it’s how you’d want a 356 to be, and proof that backdated Porsches don’t have to be furlongs of Alcantara and a Momo Prototipo. There’s now air con and electric windows (using bespoke solutions, of course), as well as probably the most elegant door bars you’ve ever seen. Some way from a 1951 Le Mans car perhaps, if actually an unexpectedly pleasant place to sit.

Not least as the SL glides down the road in that deft, delicate way that only very light, very expensively suspended cars tend to do. There’s so little inertia, so little mass to control, that you’re soon seeking out direction changes and imperfections for the sake of it, just to experience once more how capable this little Porsche is. Maybe the steering isn’t perfect in terms of feel, though there’s no doubting the alertness and accuracy. There’s a mid-engined immediacy to the 356, without any of the delay or hesitation that might be expected given the engine’s location.

What a little firecracker of a flat-four, too. To all intents and purposes, this is now a new engine from TK, 2.3-litres in capacity where even the very latest 356s only went to 2.0-litres. The earliest versions, from the late '40s to the mid '50s that this most closely resembles, were never larger than 1.5. So it’s a pretty drastic change, another labour of love in the workshops to make the best 356 engine possible. And it’s a gem: smoother than the similar configuration in a Kamm 912, tremendously responsive and singing for the redline in a way you might not expect from such a relatively large capacity four-cylinder. With 180hp or so moving about a tonne, acceleration is brisk without being outrageous. It’s the perfect accompaniment to a chassis of such energy.

With early 911s providing the inspiration for some of the SL’s suspension setup, the five-speed gearbox comes from a 993. Which wasn’t the work of a moment to squeeze into a 356 (not least with the larger engine), but making the challenging look seamless appears to be the TK way. Arranged in a dog leg, it’s a great complement to the flat-four’s fizz: once a rangey first is done the ratios are short, so flitting straight up and down between second and third is a cinch. Fourth and fifth are way easier than you might think for an old Porsche manual in an even older Porsche, and it really doesn’t take long to be merrily buzzing up and down gears like a gentleman racer on his way home from the circuit.

Indeed when the SL all comes together - the vibrant powertrain, the quality of the chassis and the joy of just being in it - the feel is very much of a classic motorsport machine. One built for the hillclimbs of Europe, or sprinting, or tearing around a track with lots of similarly equipped machinery. Only this race car is beautifully assembled, painless to drive slowly, and protests not one bit at the endless three-point turns and idling that make up the majority of a photoshoot. All of which it would be reasonable to expect of a totally new, re-engineered car, but so convincing is the SL as a classic experience that it’s hard to get your head around. What you see, hear and feel is how you always hoped a 356 would be (and secretly know it never would), with the dependability and usability of a Cayman. Even immediately after the XK120, the SL is alive and very exciting.

In fact, probably the greatest compliment that can be paid is that what Thornley Kelham has created feels like it could have come straight from Porsche. If the desire to create more Sonderwunsch builds as part of the Sportwagenschmiede ‘35 plan produced this, it would be raved about. Those bored of green over tan 911s with ducktails and Fuchs, but with a yearning for a glorious classic Porsche experience, should get their name down for one of the 50 SLs. Some may initially object given how many fewer 356s there are compared to the car that replaced it, but it really is hard to take issue with the project once you’ve seen the care and commitment that’s gone into it. Or, even better, had a fabulous few minutes behind the wheel.

SPECIFICATION | THORNLEY KELHAM EUROPEAN SL

Engine: 2,332cc, flat four
Transmission: 5-speed manual, rear-wheel drive
Power (hp): 180@6,100rpm (optionally 200)
Torque (lb ft): 180
0-62mph: c. 6 seconds
Top speed: N/A
Weight: 900kg dry
MPG: N/A
CO2: N/A
Price: TBC