We go to great lengths to ensure that Retropower projects follow a well thought out pre-established plan, a way of minimising wastage of time, resources and effort. The very nature of creating brand new cars from decades old ones means that, however much we try, changes happen; builds take on a life of their own, well thought out plans fall by the wayside and, just occasionally, a car winds up with a totally different engine to the one envisioned at the very beginning. Kenny’s RB25DET powered Manta 400 replica is a prime example of this.
Kenny’s plan was centred around the desire for a comfy cruiser, the kind of car capable of crossing continental Europe without drama, and with provision made should the worst happen and said car wind up stationary by the side of the autobahn. So far, so Retropower. Where things get a little more interesting is when the time came to select an engine, with a number of different motors in the frame at one point or another.
A Z20LEH, the Astra VXR engine, was discounted thanks to its large and awkwardly placed water housing, with an SR20DET then thrust to the fore. It was only when we began hunting for a suitable Nissan S14 donor vehicle (at the beginning of their ubiquitous drift career) that we realised that we could acquire an R33 GTST, the two wheel drive Skyline, for the same money if not less. The wheels were thus set in motion, and it wasn’t long before a slightly down at heel mid ’90s Nissan was dropped outside Retropower waiting to be cannibalised.
Kenny had sources a suitable Manta GTE for the project by this point, a shell we set about stripping back and ridding of rust right away, then painting in Aston Martin Morning Frost. This done we set about devising how to physically fit the Skyline’s bulky running gear into the ’80s Opel, a more involved task than you might imagine. Indeed, we were eventually left with a near custom chassis from the bulkhead backwards – including the bulkhead itself! It was quite some undertaking but one which allowed us to dry-mount much of the essential Skyline hardware, including the engine, gearbox, rear sub-frame (plus adjustable Driftworks kit) and differential. Everything was subsequently stripped, media-blasted and rebuilt.
The RB25DET has gained an unmatched reputation for producing ungodly power figures, and while this build was never destined to be the most extreme of Retropower creations, we thought it remiss not to at least pay homage to the engine’s performance potential. It was therefore rebuilt, gaining forged pistons and steel rods along the way, alongside aftermarket inlet manifold, Garrett GT35 turbo, Turbosmart wastegate and dump valve. Cooling was entrusted to a sizeable Skyline Front Mounted Intercooler, with similarly sized oil cooler and radiator.
It seemed odd to transplant so much Skyline hardware without also taking advantage of its relatively advanced capabilities, which is why we plumped for DTA S80 management, a system noted for its ability to run traction control when paired with trigger wheels and sensors on all four of the Manta’s wheels. This means Kenny has freedom to programme how aggressive he wants the system to agree, while switchable boost gives him control over how unhinged he wants this Manta to be – a mere 350bhp in ‘mild’ mode, 450bhp in ‘manic’ mode.
A mix of Skyline and Manta kit makes up the chassis, with Bilstein coilers on custom poundage springs, the rears having been custom made for the installation by the factory in Germany. They can therefore take account of the Nissan mounting at the bottom (Skyline hubs are used throughout) and Opel fixing at the top. Skyline brakes now lurk beneath the wheels, custom 8x16in Revolution Millenniums fore and aft.
The choice of engine might’ve changed as the build progressed but neither Kenny nor anyone at Retropower lost sight of the need for this car to be comfy as well as fast, something reflected in its interior. The seats are reclining Recaros (re-trimmed in 400-aping cloth), while the custom centre console can support USB ports, cupholders, fuse box, and a very special plaque signed by the one and only Jimmy McRae. There’s also a weld-in OMP cage and, mounted in the space where thee deleted rear bench once was, a spare Revolution wheel, wheel brace and trolley jack recess – further evidence of this Manta’s intended use as a long distance cruiser.
Completed towards the end of 2017, the Manta was dropped back to a decidedly chuffed looking Kenny. It has since been used for the odd European jaunt, including a trip to France for classic Le Mans in June.