Every so often a build comes along that rewrites the rulebook on what a genteel 1960s roadster is supposed to feel like, and this 1963 Mercedes-Benz 230SL is exactly that kind of machine. Beneath its patinated red paint and pagoda-roofed silhouette sits a naturally-aspirated AMG V8 making a claimed 354 horsepower, routed through a proper six-speed manual. It's the sort of restomod that keeps our news feed busy, in the same vein as this 550-HP HEMI Challenger restomod — old-school looks, thoroughly modern muscle underneath.The naturally-aspirated 5.4-liter M113 AMG V8 from a 2002 S55, good for 354 hp. Photo: Bring a TrailerWhen the 230SL left the factory in 1963 it carried a 2.3-liter inline-six good for around 148 horsepower — brisk for the era, but hardly ferocious. This car flips that story entirely. Nashville-based Kwiek Classics dropped in the naturally-aspirated 5.4-liter M113 V8 sourced from a 2002 S55 AMG, a motor rated at 354 horsepower and 391 lb-ft of torque in its final naturally-aspirated year. The shop reports the tuned output likely edges above the factory figure thanks to a reworked ECU, so the performance gap versus the original six-cylinder is night and day.The Kwiek Classics RecipeFounded by Matt Kwiek in late 2022, Kwiek Classics has built its reputation on slotting AMG drivetrains into vintage Mercedes-Benz chassis, with the M113 V8 becoming something of a signature swap. Before installation on this car, the engine received a fresh valve job, new bearings and seals, a lightweight flywheel, a new clutch, and that custom tune. A stainless steel exhaust with tubular headers exits through twin tips positioned close to the factory outlets, so the car keeps its period silhouette while sounding nothing like a 1960s tourer.AdvertisementAdvertisementPower reaches the road through a Mercedes 716-series six-speed manual that bolts straight to the M113 with no adapter required — a big reason the combination has become a favorite among manual-swap builders. From there a custom driveshaft feeds a Quaife limited-slip differential with 2.82:1 gearing, giving the little roadster genuine long-legged usability to go with its added grunt.Chassis, Brakes And SuspensionMaking 354 horsepower usable meant rethinking the underpinnings. Kwiek Classics ditched the original swing-axle rear and grafted in a complete rear subframe from a C209-generation CLK, bringing multi-link geometry and rear disc brakes along with it. The two cars happen to share a nearly identical rear track width, which made the swap feasible, though new mounts still required serious fabrication. Up front the original suspension was retained but heavily refreshed, with springs and dampers dialed in across roughly 8,000 miles of post-build sorting.Braking hardware is equally resourceful. The front stoppers are 560SEL-spec units from the W126 S-Class, fitted with custom-machined billet hubs to mate to the 230SL's original upright geometry, while a compact BMW hydraulic booster supplies assist at all four corners. The car rolls on powder-coated 15-inch steel wheels wrapped in 205/65 Michelin Defender rubber, keeping the look purposeful rather than flashy.Rally decals and a roundel echo Eugen Bohringer's 1963 Spa-Sofia-Liege-winning 230SL. Photo: Bring a TrailerPatina Over PolishRather than chase a concours finish, the builder leaned into character. The bodywork wears an older 2006 respray in red that wasn't redone during the conversion, so expect some paint imperfections, pitted chrome, and aged wood trim inside the cabin and on the removable hardtop. Period-correct racing decals and a roundel nod to the livery of Eugen Böhringer's 230SL, which famously won the grueling Spa–Sofia–Liège marathon rally just months after the model's 1963 debut. European-spec headlights, rally-style spotlights, and a fresh black soft top round out the exterior.AdvertisementAdvertisementInside, a pair of Cobra fixed-back bucket seats trimmed in black cloth and vinyl sit ahead of matching door panels fitted during the build, with a Nardi three-spoke wheel facing the original factory instruments — some of which the seller notes work only intermittently. The five-digit odometer reads 12,000 miles, roughly 8,000 of them added under current ownership, though the car's total mileage is unknown. This is reportedly the first and so far only 230SL that Kwiek Classics has completed.A KWIEK badge and twin exhaust tips exit near the factory location. Photo: Bring a TrailerNow offered on dealer consignment through Ottis & Co. in California, the car comes with its body-color removable hardtop and a clean Tennessee title. If restomodded classics are your thing, it slots right alongside other reimagined icons we've covered, from this fuel-injected 1966 Chevelle SS396 to this Cummins-swapped 1941 Dodge WC-12. Photos courtesy of Bring a Trailer.⚡️ Read the full article on MotoriousSign up for the Motorious Newsletter. For the latest news, follow us on Facebook, Twitter, and Instagram.