Tsukuba Time Attack Soarer w/ 1.5JZ-GTE (2JZ-GTE block, 1JZ head) & Hollinger Trans
09-01-10, 06:03 PM
#1
Tsukuba Time Attack Soarer w/ 1.5JZ-GTE (2JZ-GTE block, 1JZ head) & Hollinger Trans
1992 Toyota Soarer
Auto Bahn Takes A Proven Drift Chassis And Converts It Into One Fast Time Attack Soarer.
When Toyota created a luxury coupe in 1991, nobody knew it would become such a cult classic. In Japan it took years for the big JZZ30 to lose value and begin appealing to performance-minded enthusiasts who saw a unique RWD platform with plenty of potential.
Takahiro Ueno of T&E has probably single-handedly given a drift image to the Soarer after he built up his powerful D1 Grand Prix machine in 2004. Its manageable chassis coupled with bulletproof Toyota engineering made it well respected and easily spotted in a sea of Nissan drift cars. But you might be surprised to find out that the Auto Bahn Soarer you see here actually has nothing to do with sliding around racetracks in big clouds of tire smoke. In fact, Kawai-san at Auto Bahn was asked by one of his friends and customers to create a time attack machine that would compete in the Tsukuba Super Lap Battle back in December '09.
1992 Toyota Soarer Engine
"Why a Soarer?" I asked Kawai-san. "Why, with all the other cars available, did your customer choose a JZZ30?" His answer was simple, and it actually made sense: "We just wanted to see if we could do it." The idea was to dip below the coveted 1-minute lap at Tsukuba - not an easy task, to say the least, especially with their choice of car. But Kawai-san didn't leave anything to chance and got cracking by addressing what was potentially the Soarer's biggest disadvantage: its chassis.
In the early '90s, Toyota used to build tanks, not cars. Everything that came out of its factories was massively over-engineered, and for the Soarer the emphasis was put on luxury and smoothness. This meant weight, and lots of it - the big coupe hit the scales at a little over 3,500 lbs, something that is considered almost lightweight by today's standards. The car was stripped to its bare chassis and stitch-welded to guarantee optimal rigidity. The only factory part of the trim that was reused was the main dash, or half of it at least. The lower section was removed and a very simple dry carbon center console was created to house a pair of GReddy gauges and the HKS EVC control unit. More GReddy gauges replaced the stock main instrumentation and were joined by an Auto Meter tach and shift light. The transmission tunnel consists of more dry carbon paneling and a very simple gear lever rising straight up next to the Momo steering wheel.
1992 Toyota Soarer Steering Wheel
A heavily bolstered Bride bucket seat just manages to clear the center and side-bars of the rollcage and is balanced out by the Optima RedTop battery fitted on the passenger side of the car. The quest to keep the Soarer as light as possible meant the massively heavy stock doors had to go. They were replaced with very thin dry carbon TBO pieces with an FRP back structure. Except for the front windshield, all glass was replaced with acrylic type windows to shave more weight.
Aesthetically speaking, staying away from a drift look was going to be very difficult because almost all of the Soarer aftermarket is drift-oriented. Kawai-san tried to overcome this by mixing the Origin front bumper with his own FRP wider front and rear fenders, tying everything together with the T&E side skirts. The unpainted Rasty hood and RDD GT-wing, both made from tough carbon-Kevlar, throw a more grip-oriented feel into the mix. The Auto Bahn rear diffuser and vortex generators are also key items that lend to the time attack theme. The stock mirrors were replaced with a pair of tiny carbon-fiber race motorcycle pieces. A staggered set of bronze wheels from Rays finishes off the exterior, 17-inch Volk Racing TE37 up front and 18-inch 57Pro Gram Lights in the rear, all wrapped in Advan A050 semi-slick tires. Kawai-san has custom graphics made up for the car to give an authentic feel to the project, with the Auto Bahn name on the sides hinting to those in the know that this is no drift car.
Making the big Soarer handle was no easy task, and Kawai-san knew he would have to use proven Ikeya Formula suspension parts to make the big coupe corner. Adjustable top arms front and rear allow for accurate control of negative camber, which has been dialed in aggressively for this setup. Roll center adjusters are built in to the lower pillow-ball arms while rear traction rods help eliminate bumpsteer and get the most grip out of the setup when powering out of corners. The revamped suspension layout is joined by a set of Spirit adjustable coilovers with custom valving for this setup. Even though more than 450 lbs were removed from the Soarer, a Brembo F50 big brake kit was still a must because speeds of 125 mph speeds are reached on the backstraight at Tsukuba. At the rear, thanks to Toyota part interchangeability, a set of JZA80 Supra calipers and discs were fitted to create a nice and balanced setup.
1992 Toyota Soarer Rear Spoiler
Power, and lots of it - 720 hp and 680 ft-lbs of torque, to be exact - was achieved. With the extra displacement gained from using a 3.0-liter 2JZ block, the guys at Auto Bahn knew the HKS T51R turbocharger was the perfect choice for the build. Its potential to make massive power - around 1,000 hp is possible from this snail - would allow them additional scope for the future if more power was required from the motor. The 1JZ head, with its built variable valve timing and upgraded HKS camshafts, has allowed for optimal control of lower- to mid-rpm torque to get nice, progressive delivery of power when the T51 gets on boost. The stock crank has been mated to HKS H-section connecting rods and oversized HKS forged pistons, but without a doubt, the key to Kawai-san's build is the increased compression ratio of 9.5:1, which helps spool up the turbine faster and provide better throttle response.
The custom fuel delivery system was also designed with time attack in mind - a tiny 8-gallon tank replaces the big stock unit and only allows a couple of laps before having to bring the Soarer in for a refuel. With close to 700 ft-lbs of tire-melting fury available, a Hollinger 6-speed sequential was mated to an OS Giken triple plate clutch in hopes of creating a reliable and durable drivetrain setup.
1992 Toyota Soarer Interior
Kawai-san says that traction is an issue, but thanks to the engine's good throttle response, juggling such power levels isn't as impossible as it may seem. When we saw the Soarer at the Tsukuba Super Lab Battle, it seemed to be struggling to put power down on corner exit, probably due to the cold track temperatures. At that time the car's owner was unable to dip below the magical minute lap maker, but with warmer weather at another outing, it ran a 59.681-second lap. Not bad at all considering that was only the Soarer's second outing.
Kawai-san aims to dip deeper into the sub-minute marker, which considering the chassis and weight handicap, may be hard to do, but with a little more development time and turning the wick up on what seems to be a 1,000hp capable engine setup should get him the results he wants.
1992 Toyota Soarer Performance Parts
1992 Toyota Soarer Trunk
Specs & Details
'92 Toyota Soarer
Engine Toyota 1.5JZ-GTE (2JZ-GTE block, 1JZ-GTE head)
Engine Modifications HKS exhaust manifold, T51R turbine, GT external wastegate; Auto Bahn custom turbine outlet & front pipe, custom titanium exhaust system; HKS forged pistons +1 mm, H-section connecting rods, 2 mm metal head gasket (compression up to 9.5:1), camshafts 264-degree intake & exhaust, slide-type cam pulleys, SPF foam filter; Auto Ban custom aluminium intake pipe; HKS triple-core intercooler; Auto Bahn custom aluminium intercooler piping; Kinokuni racing aluminium tank; Bosh Motorsport fuel pumps (x3); Auto Bahn custom fuel collector tank, braided fuel line & custom fuel system layout; Sard FPR, 850 cc/min injectors (x6), aluminium racing radiator; Trust air separator tank; Setrab 34-row oil cooler
Engine Management HKS F-Con V Pro ECU
Drivetrain Hollinger 6-speed sequential gearbox, OS Giken triple plate clutch, Cusco 2-way LSD Suspension Spirit adjustable suspension kit; ARC stabilizer bars (f/r); Ikeya Formula camber-adjustable front upper arms, front lower pillow-ball arms with roll-center adjusters, camber-adjustable rear upper arms, adjustable rear lower arms, adjustable rear toe rods, adjustable traction rods
Wheels, Tires & Brakes Volk Racing TE37 10jx17" +22 (f), Gram Lights 57Pro +15 10.5Jx18" (r), Yokohama Advan A050 255/40/ZR17 (f), 265/35/ZR18 (r), Brembo F50 front calipers w/ Rdd 355 mm rotors, JZA80 Supra rear calipers & rotors, Endless brake pads, BNR32 GT-R brake master cylinder
Exterior Origin front bumper, carbon canards; Rasty carbon-Kevlar hood; Auto Bahn FRP aero front fender; T&E side skirts; TBO dry carbon doors; Acrylic side glass; Auto Bahn rear overfenders, rear diffuser; Carbon-Kevlar vortex generators; RDD carbon-Kevlar rear GT-wing; acrylic side glass, rear glass, rear side glass; Auto Bahn carbon mirrors
Interior Custom stitch-welded chassis, custom welded-in rollcage, custom dry carbon center console & shift lever, custom lower dashboard section; Bride racing bucket seat; Sabelt racing harnesses; Momo Race steering wheel; custom dry carbon center console; GReddy gauges (fuel pressure, oil pressure, oil temperature, water temperature, boost), HKS EVC boost controller; Sport Comp Auto Meter fuel gauge, rpm gauge w/ shift light; HKS Circuit Attack Timer; Optima Red Top dry-cell batter relocated to interior
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From the August, 2010 issue of Modified Mag
By Dino Dalle Carbonare
Photography by Dino Dalle Carbonare
