C-R-A-S-H!!! That's the sound of the WRX world record being smashed into little-biddy pieces by Dominic Rigoli. Yes readers, with a 10.55 second pass under its belt, this is now officially the fastest quarter mile Rex in the world. And that's some achievement given the fast Subaru's high profile.
So let's not waste any time waffling - let's pull this beast apart bolt-by-bolt!
The engine - a dyno certified 443 horses at the wheels!
This car carries an EJ20 turbo engine that was pulled from Dominic's previous green '96 WRX, which ran a best time of 12.0. But since the green car was so schmick, he couldn't bare to strip it down and go ape. The answer was to re-vamp this $18,000 white '96 WRX, which had been damaged. Not one to hang around, the complete build up has taken only about a year.
And this it isn't just another Rex with a big turbo and a helluva lot of boost - there's much more to it than that. Lead on by the 22B Impreza, Dominic set off in search of a way of pumping up the EJ20's cube count. Two litres simply wasn't going to be enough. The answer came from the 'States in the form of a BPM Motorsport stroker kit, which cost approximately $6000. This arrived complete with a 2.2 litre stroker crank (the bore diameter is left standard), forged pistons delivering a compression ratio just below 8.0:1, billet rods with stronger bolts, rings and bearings.
Dominic and his highly experienced father Tony, assembled the motor using an O-ringed block as the base. An external blow-by canister was also deemed a requirement, as oil might otherwise find its way into the intercooler under the anticipated high boost level. Amazingly, the engine retains its standard cams and heads (which shows there's still more performance left in the car!).
A heat wrapped OE exhaust manifold (with a custom top section) takes the big-banger's smog up to the biggest turbo we've ever seen underneath a WRX's bonnet. ProSpool recommended using this hybrid T60/T70 Turbonetics T-series roller bearing turbo, teamed with a Turbonetics 42mm Racegate to bleed off excess gas. With a Blitz Dual Solenoid control system wired in, boost pressure has recently been raised from 22 to a gut-busting 35 psi! This new boost level is enough to generate 443 horses on Tony Rigoli's four wheel chassis dyno, while the previous 22 psi was enough for "only" 360hp...
With some serious work cut out for it, a full width Mick's Metalcraft air-to-air intercooler is hung out front to bring the intake temps down to a sane level. Like many serious WRX tuners, Dominic also flipped the standard throttle body over to the front of the intake plenum - which meant removing the air conditioning system so he could run the polished intercooler pipe straight in. The rest of the intake system is made up of silicone hoses, heavy-duty hose clamps and a RBR blow-off valve.
A Microtech MT8 programmable computer incorporating a MAP load sensor (which deletes the factory airflow meter) controls a set of four 860cc Mazda Series 6 RX-7 injectors working with a Malpassi regulator.
A Bosch Motorsport pump drawing from an in-boot surge tank supplies these squirters with a reliable stream of BP C16 fuel. Octane booster is also added to the tank at the track.
Two pairs of Bosch high-energy coils, Magnecore leads and standard platinum plugs deliver the kind of spark strength required to ignite the mixture. The Microtech computer also cuts ignition at a skyward 9500 rpm. So despite its larger capacity, this motor certainly still likes to wind up!
So is it a bit of a grenade or what?
Dominic tells us the only engine problem he's had so far is three sets of leaking copper head gaskets - which, he says, is a side effect of the high boost pressure. However, a recently installed set of head studs and a thorough sorting of the cooling system appear to have remedied the problem. Oh and, curiously enough, the standard radiator over-flow reservoirs kept blowing apart under the extreme boost pressure. A custom fabricated aluminium tank fixed that one.
And what about the clutch and gearbox?
The limiting factors to WRX performance have apparently been overcome. Dominic's car utilises a lightened steel flywheel (the original one started to crack under extreme heat) and a Jim Berry combination of the stock clutch plate (with a standard lining but a stronger centre) mated to a massive 4300lb pressure plate. In short, there's bugger-all slip.
Then, like many people, Dominic discovered first hand that the WRX's gearbox is a joke when you've got boosted power together with a decent clutch. After getting tired of wiping out one standard gearbox per drag meeting (and with only about half the current power on tap!), he enrolled the services of Sam. That's the Sam of Sam's Gearboxes. Initially, Dominic tried Sam's near-$4000 Stage One 'box with its billet shafts and gears. But under the strain of the mega EJ motor (which was set at 22 psi at the time), it broke second gear after only two meetings. Hmmm...
After that, Dominic went whole-hog and moved up to the 6500-odd dollar Stage 3 unit - which is probably the toughest WRX gearbox money can buy. This feisty beast features billet shafts and gears, as well as dogs on every gear except fifth. Dog engagement means Dominic has to match engine revs when changing up, and slip it into neutral whenever coasting down to a halt.
But the newfound ability to launch at over 9000 rpm without stripping teeth has been instrumental in clinching the world record crown. "I just hold it flat and take my foot off the clutch" laughs Dominic. That's the technique that best spools up the big turbo.
The 10.55 second pass...
On only its first session running 35 psi boost and no exhaust or air filter, Dominic creamed his previous best time of 11.1 seconds with a 10.8. And only a week later, that was dropped to 10.55... As per usual, the car was run with a stripped interior (no rear seat) and a set of circuit slicks on the stock 15 inch WRX alloys. Without the sticky rubber, Dominic says the car will spin street tyres all the way through first and second gear. And, of course, this is a constant all-wheel-drive car!
Dominic says "I launch it at over 9000 and it have a fair bit of wheelspin. It takes off fast and I flat change into second with just a dab of the clutch pedal. Second is the real power gear - you don't reach full boost in first - and it feels strong all the way to the line. The change from second to third is slow though, we've got some linkage problems at the moment. Yeah, and it's always a bit of a handful to keep straight."
Not surprisingly, the aura around Tony Rigoli's new Gold Coast camp is pretty special at the moment. You can't blame the guys - especially when they're busting in the knowledge there's still more performance left in the car. Using their in-house chassis dyno, they'll tune every last kW out of it and there's even a lighting-quick sequential shifter in the pipeline. Revision of the stock suspension is on the agenda too.
So what's the long-term goal? To crack low 10s, and then move everything over to a 2-door WRX shell they've got lying around! But surely - for now - they'll be able to kick back and watch everyone else try to catch up. Lucky there's some nice sunny beaches around the Gold Coast...
Contacts:
Tony Rigoli (Gold Coast)
+61 7 5528 4666
ProSpool
+61 7 3349 9511
Mick's Metalcraft
+61 2 9755 7137
Australian Competition Clutch Supplies
+61 7 3891 6114
BPM Motorsports
www.bpmsports.com
