Does measurement matter? It’s a query that has plagued humanity for hundreds of years. In terms of turbochargers at an occasion like Gatebil although, greater is at all times higher. And what’s higher than one huge turbo? Two, after all.

Throughout my current weekend at Rudskogen Motorsenter in Norway for the largest Gatebil occasion of the Scandinavian summer season, I noticed numerous turbos. Huge ones. In pairs. Strapped to diesel engines. So, for my last 2023 Gatebil Rudskogen occasion story, I believed I’d check out some the wildest compound turbo setups I discovered within the paddock.

Let’s begin with the Bekkevold brothers, Marius and Jonas, whose diesel-powered Mercedes-Benzes are sights to behold once they’re out on observe doing what they do finest. Their engine bays have been sights to behold in between circuit periods too.

Let’s start with Marius’s turbo setup, as fitted to the Mercedes-Benz OM648 3.2L straight-six diesel engine in his 1990 W124 sedan. Compound turbo preparations are frequent in OEM diesel turbo purposes, and it’s simple to grasp why they’re carried over into {custom} aftermarket setups like this one.

Very principally talking, in a compound setup a smaller turbo (high-pressure turbo) and a bigger turbo (low-pressure turbo) work in sequence. Air feeds into the bigger turbo first, the place it’s compressed after which fed instantly into the mouth of the smaller turbo, which in flip feeds into an intercooler after which the engine itself. Because the engine RPMs rise, the bigger turbo spins faster and produces enhance, and that’s fed into the smaller turbo as soon as extra. In Marius’s case, the smaller turbo is a reasonably massive Holset HX40, which by itself would be laggy. On this situation although, the bigger turbo within the setup – the BorgWarner S476 mounted up high – ensures that the Holset produces enhance from low-RPM after which retains making it proper by way of the rev vary.

Different upgrades in Marius’s setup embody Dieselmeken race injectors, a high-pressure stroker pump and a Baldur DSL1 piggyback ECU.

Jonas’s compound turbo setup in his OM648-powered 1985 S123 is analogous, however makes use of Holset HX40 and HX60 turbos and engine administration from Black Smoke Racing.

Each automobiles are pushing someplace round 570whp, and depend on Mercedes-Benz 722.6 computerized gearboxes fitted with OF Gear controllers. These standalone controllers sit instead of the 722.6’s manufacturing unit TCU, and permit Marius and Jonas to have full management over their transmissions with handbook shifting and the choice of paddles.

Subsequent up, we’ve got one other diesel Mercedes-Benz. Underneath the pores and skin it’s a W203, however the exterior resembles a W204 C63 Black Collection. As soon as once more, it’s OM648 powered. This one’s been constructed up with {custom} cast pistons and H-beam rods, and race-spec cams and valve practice. ARP fasteners maintain all of it collectively.

The compound turbo setup includes a Holset HX40 and HX60, each custom-modified for elevated enhance manufacturing. The result’s a wild 700whp and 1,200Nm.

Final however actually not least is Why Not? Racing’s BMW E61 wagon.

Are you stunned to see one other compound turbo setup on a diesel engine? I didn’t assume so… This time we’ve got a BorgWarner S200 VGT paired with a jumbo Holset HE551V.

Once I checked out the again of the wagon, I instantly considered Mad Max for some cause. The 28-litre-capacity cooling system includes a Volkswagen T5 radiator up high and BMW E61 radiator on the backside, plus a 12-row diesel gas cooler. There’s additionally a Davies Craig EWP150 electrical water pump in there someplace…

Diesel-powered, compound-turbo-equipped drift machines are a Scandinavian staple, they usually’ve been an enormous a part of Gatebil for a very long time. Bellowing white smoke from their tires and black smoke from their exhaust programs, they won’t be essentially the most environmentally-friendly automobiles, however they positive are enjoyable to take a look at it – whether or not drifting or – as we’ve seen on this submit – parked up within the paddock.

Alen Haseta
Instagram: hazetaa