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This article was first published in 2002.
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It cranks out 764hp (570kW) running 98RON premium unleaded and with only 25 psi boost.
On a diet of C16 race fuel it'll bust an amazing 937hp (699kW) with 34 psi boost.
Oh, and we're casually told it's capable of over 1000hp (about 750kW) if it's ever decided to 'lean on it' a bit harder...
With vital statistics like that, it's no surprise that this is the most powerful RB26DETT engine ever bolted together in Australia; if anyone can out-do this, by all means send us your graph taken from an engine dyno! Before we jump straight into the tech nuts-and-bolts, though, let's first come to grips with what 937hp actually means. We're talking three and a half times the factory power output of a Nissan Skyline GT-R, well over twice the output of the 'awesome' 5.7-litre Calloway C4B 300kW engine and - last but not least - 50 percent more grunt than the 6-litre V12 McLaren F1! Forget about the numbers for a moment, though, because watching an engine like this slog it out on the dyno is definitely a lifetime experience.
Okay, now we've got things in perspective, let's get greasy...
It all Started Six Years Ago
Simon Gischus - the lead man of Nizpro, Melbourne - has had to wait six years for the opportunity to fire up this mad piece of machinery. "I'd built the long engine back in about 1996 - everything from the sump to the rocker cover, but without the turbo and all that - and it was planned for a customer with a VL Turbo. Anyway, it all fell through and the thing's been sitting here collecting dust ever since." Only now has the project been re-awakened.
So what kind of good gear do you find inside a 1000-odd horsepower Nissan GT-R engine?
Starting at the floor, the sump is a standard RB26DETT item that's been modified to suit a 3-litre RB30 bottom-end. If you want bulk power out of a GT-R engine, it obviously makes things much easier if you stretch the standard 2.6-litre displacement out to 3-ish litres. While we're down there, there's also a hi-volume Nizmo oil pump and a slightly relocated pick-up (another requirement to suit the 3-litre bottom half). Interestingly, the standard main bearing cradle incorporated into the bottom of the RB30 isn't strong enough to cope with such torturous conditions, so Nizpro transformed a 2-inch thick slab of steel into a beefier version.
The block itself is an early Nissan/Holden RB30 naturally aspirated unit. Simon informs us the earlier blocks are slightly thicker - and therefore stronger - than the later production models. Overbored by 1mm, its total swept capacity is up to 3.1-litres - about 20 percent larger than the standard GT-R engine.
The rotating and reciprocating assembly includes - amazingly - a stockie RB30 crankshaft that's merely been nitrided and ground. Nizmo competition VG30 conrods bear the brunt of loads between the crank and pistons, which are dished Cosworth jobs providing a static compression ratio of 8.0:1 (relatively healthy for a mega-power turbo engine). Big-end bolts are Nizmo items, while Nizpro made the main bearing and head studs - there was nothing else available off-the-shelf at the time of assembly. Rings and bearings are standard Nissan - even the head gasket is standard, working with Nizpro W-rings.
Sitting proud atop this big cube bottom-end is a Skyline RB26DETT, 24-valve alloy head - boasting a few tweaks, of course. "The head - which was bought brand new - copped a 3-angle port job and some general tidying up and went together with standard valves, Iskenderian springs, Del West titanium retainers and Nizmo bucket lifters," says Simon. The camshafts are slightly more aggressive than standard, providing an advertised 306 degrees duration and about 11mm of lift. Cam timing has been set up using custom adjustable sprockets.
Bringing Together the Turbo and Management System
The turbo and engine management system was tackled only months ago and - despite current trends - Simon likes to make the point that none of the major components came from Japan. There's no need for mega-buck accessories bearing names like OS Giken, Trust or HKS.
Sausages of exhaust gas are channelled through a beautiful Nizpro fabricated 6>1 stainless steel manifold into a massive '1000hp' steel-bushed Garrett turbocharger. You won't find any external wastegate fitted to this engine - instead, Nizpro controls boost pressure using a pair of aftermarket blow-off type valves mounted on one of the post-intercooler pipes. These are opened by the MoTeC management system to vent a portion of intake charge, thereby limiting exhaust gas flow and turbine speed. The valves are opened pneumatically, thanks to a MoTeC-controlled electronic solenoid.
And now onto the intake...
A 3-inch mandrel bent pipe routes compressed air through Nizpro's water-to-air intercooler, which is specially built for their dyno - a giant front-mount air-to-air intercooler will be coupled to the engine when it makes its way into the nose of a R33 GT-R. Interestingly, the engine retains the standard six-throttle intake manifold. It has recently become tradition for many big-hp GT-R engines use a large single throttle plenum, but Simon says this is largely to help obtain a better engine vacuum signal for the engine management, rather than to improve airflow. "I'd argue that the six-throttle arrangement gives it much better throttle response, though. You've got a 3.1-litre, low compression engine with big cams in a 1500kg car - it really needs 20 or 30 psi boost shoved into it to make it go if you ask me."
To keep up with the fuel requirements of a 1000-odd horsepower GT-R engine you need some serious hardware. This engine employs six 1600cc injectors and a Bosch 3-Bar pressure regulator hung off a custom Nizpro fuel rail, while fuel delivery - once the engine is in the car - will be left to twin Bosch 984 pumps.
The direct-fire ignition system, however, remains completely standard. Simon informs us this engine loves to rev and, therefore, it doesn't need to make insane amounts of torque - this saves things like conrods and bearings and enables the standard ignition system to get by.
Simon has come up with a from-scratch set of fuel, ignition and boost control maps using a current series MoTeC M800 ECU. "There's nothing particularly special in the fuel or timing," says Simon, "it runs between 22 - 28 degrees of timing and about 0.88 Lambda (12.9:1 AFR) under load." He adds, "At 8400 rpm we pull a heap of boost out and make it feel soggy, just before the 8500 rpm soft limiter." Boost limits are set depending on the fuel brew used - up to 25 psi can be run using pump PULP.
As mentioned, the combination of pump fuel and 25 psi is enough for this engine to muster an incredible 764hp without fear of detonation. Squirting "undetonatable" C16 race fuel through the injectors, however, the power envelope is well and truly open. A tentative push up to 30 psi boost yielded 854hp and further 4 psi elevated standings to 936hp. Seen here is the 764hp premium unleaded run (plotted in blue) versus the 854hp 'low boost' C16 run (plotted in red) - unfortunately, a plot of the 937hp run was unavailable, but we did see this power figure for ourselves on-screen.
Take a close look at the graph and you'll see how this beastie makes the standard GT-R's maximum power output at just over 4500 rpm and, from there, power doubles over the next 1000 rpm! The rate of power increase then tapers off, with maximum power seen at around 7500 rpm.
"It's the sort of engine that just loves more boost," smiles Simon. "We could put in a bit more and I reckon we'd get, maybe mid-1000s, low-1100s..." - horsepower that is...
An Affordable Everyday Driver?
So how much does a fairyland engine like this cost to build, you ask? Well, Simon reckons inclusive of everything it'd run to about AUD$40,000 - assuming you've got your own engine to begin with. It's like the saying goes - speed costs money; how fast do you want to go?
And, look, don't fool yourself into thinking a 1000-odd horse Skyline GT-R engine is something for regular street use. It'll absolutely gulp fuel when on boost and - as Simon says - with this amount of power, it's not going to be a long-life, maintenance-free engine. What's more, its power is largely unusable on the street - it'll either break its gearbox launching from the first set of traffic lights or it'll break (ie kill) the driver.
It's something to marvel at, but a 1000hp 'streetcar' - even a GT-R - really is stretching it a bit!
Contact:
Nizpro
+61 3 9761 1522
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