Running wild: Hi-Power-built 500kW RB26 S15

13 December 2017

 


 

When Hi-Power Performance was given an open slather on a worn S15, the results were pure street brawler

“What the hell is this?” was the question spurted by the infamous Dom in The Fast and the Furious when Brian Spilner showed up at his workshop with a wreck of a Supra on the back of a tow truck, ready to build that 10-second car. Well, this might not be a Supra, and running 10-second passes was never the goal, but a similar scene played out at Hi-Power Performance when a tow truck backed up to the workshop door some six months ago to deliver an S15 chassis. “It was a real mess. It had been painted, but it had no engine, interior, or boot. Other than the fresh paint job, it was a piece of sh*t, really. The only instruction from the owner was to keep the theme red and black, and build it as if it was your own,” Ethan Lowe of Hi-Power Performance recalls. 

The S15 Rocket Bunny kit swallows the 18×10-inch (-21) and 18×12-inch (-41) Work Meisters without breaking a sweat. Like the front guards, the rears have been tubbed to allow for the ride height

 


 

Now, this might sound like a dream build situation to most, but being able to piece together your dream S15 street car — while someone else is picking up the bill — becomes a case of knowing just how far to actually take it, especially when the owner is more than willing to go the full nine yards. But clearly the Hi-Power boys figured out that fine line and, in only five months, turned the S15 around, building a proper street brawler with more than enough kick waiting under the right foot to keep even Dom happy. 

Hell, Brian’s Supra probably never made the kinds of numbers this RB26 is capable of. While the shell might have arrived at Hi-Power with no engine, the owner did have a built RB26 ready to go in — or so he thought. A quick strip-down revealed the 26 to be a complete basket case, with a mismatch of parts. 

Spinning on the front of the RB26 crank is a Ross Performance damper with under-driven pulley and trigger-wheel kit

With the owner specifying 500kW power figures, the 26 was stripped bare and work began on rebuilding it to be capable of producing these types of numbers without grenading. 8.5:1 compression CP pistons and Eagle rods now spin within, while the head was lightly ported before Kelford cams and valve springs were installed, along with the usual ARP and ACL hardware. The turbo package is a 745kW capable Precision 6870 unit sitting on a Sinco manifold, with a 60mm Turbosmart gate handling the expected 25-plus PSI. The cold side of the system remains as the Nissan technicians specced it, with a factory plenum and six individual throttle bodies (ITBs), a method favoured by many to retain response. 

In keeping with that red and black colour scheme, a swag of parts — including the turbo exhaust housing, stainless exhaust, and Plazmaman intercooler piping — all received a coat of HPC satin black, while the intake was coated in Audi satin black and the rocker cover in Soul red. The result is an engine bay that we could stare at for hours on end, it’s just that good-looking. Even the wiring detail wasn’t left out, as they went full Mil-spec in the bay. 

The jury remains out on just how much power the combo can pony up. But, with the switch to E85 and a large fuel system capable of supporting it, as soon as the 1200cc injectors arrive, it will be dynoed by Brian from NDT Developments. Make no mistake — 500kW is the goal, and the boost and fuel will be wound up until these numbers flash up on the screen. Knowing full well the potential of the impending power, the rest of the driveline is suitably specced with a Tilton triple-plate clutch, RB25 ‘big box’ and R200 GT-R limited-slip differential (LSD) and half shafts.

It’s a suitably aggressive package to match the aggressive looks, something that Hi-power didn’t play a hand in. The shell actually arrived wearing the Rocket Bunny kit and fresh coat of Mazda Soul red, something Ethan admits is a bit backwards to the way he likes to work, as it made for a painstaking job as he tried to avoid scratching that fresh new paint. While some might say the kit is becoming a little too common around the globe these days, there is a reason for this: as long as you’re rocking the right wheels — in this case Work Meister S1s measuring 18×10-inch (-21) and 18×12-inch (-41) — it’s a combo that’s hard to beat, especially when enjoyed in the car’s natural habitat, the streets. 

With the project all but complete, it will soon be time to hand over the keys and move on to the next job. This is the one downside to building cars for others: even if it’s built like your own, there comes a time to pass it on, often without so much as a single lap around the block. But, then again, there are plenty more projects lying in wait, so it’s not all that bad. At least Ethan won’t be getting bored any time soon. 

 


 

Achieving this fitment ain’t easy. A full set of adjustable arms ensure the tyre-to-guard gap stays as minimal as possible

Built by Ethan Lowe at Hi-Power Performance
Location: Auckland
Build time: Five months 

Thanks: Michael Doran-Campbell for the fabrication work, Ryan Darrah for the wiring, Brand Studio 

Heart
ENGINE: Nissan RB26DET, 2600cc, six-cylinder
BLOCK: CP pistons, Eagle rods, balanced rotating assembly, ARP head studs
HEAD: Ported head, Kelford cams, steel head gasket
INTAKE: RB26 intake manifold, Plazmaman intercooler, custom piping
EXHAUST: Four-inch stainless downpipe, AdrenalinR muffler, four-inch shotgun tips
TURBO: Precision 6870, Sinco manifold
WASTEGATE: Turbosmart 60mm
BOV: TiAL
FUEL: Dual Bosch 044 pumps, Aeroflow surge tank, Walbro lift pump, Aeroflow fittings, -8 hard line, Aeroflow fuel-pressure regulator (FRP), Bosch 1000cc injectors, Aeroflow fuel rail
IGNITION: Spitfire coils, copper-tipped plugs, Ross Performance trigger wheel
ECU: Link G4
COOLING: Custom dual-pass radiator
EXTRA: Mil-spec wiring loom, Ross damper, Reimax oil-pump gears, custom wheel tubs, electronic power steering

Driveline
GEARBOX: RB25DET, five-speed
CLUTCH: Tilton triple-plate
FLYWHEEL: Custom
DIFF: R32 GT-R limited-slip (4.11) 

Support
STRUTS: BC Gold coilovers
BRAKES: (F) R33 GTS25-T calipers and rotors, (R) R33 GTS25-T calipers and rotors
EXTRA: Hakon adjustable arms

Shoes
WHEELS: (F) 18×10-inch Work Meister S1 (-21), (R) 18×12-inch Work Meister S1 (-41)
TYRES: (F) 225/40R18, (R) 265/35R18 

Exterior
PAINT: Mazda Soul red
ENHANCEMENTS: TRA Kyoto Rocket Bunny V2 kit 

Interior
SEATS: (F) R33 GT-R, (R) factory
STEERING WHEEL: Factory
INSTRUMENTATION: Factory 

Performance
POWER: 503kW

 

This article originally appeared in NZ Performance Car issue No. 251 — to get your grubby mitts on a print copy click the cover below