James Mackintosh 9 years ago 0

Retrospective: Toyota's Rally Special - The Celica GT-Four

Remind me later
You know, it's hard to imagine, but once upon a time it wasn't just Mitsubishi and Subaru. The Rally special used to be a requirement for competition, not a marketing package.  The Evo has a rally "heritage," but Mitsubishi doesn't even run a works rally team any more.  The newest WRX is an awesome street car, but it's hardly the hardcore homologation special it started life as.  Most people tend to think that Subaru or Mitsu started the whole Japanese Rally-Rep category, as they're the two brands most closely associated with that market.  It was Toyota, in fact, that kicked off the whole segment - as the first Japanese manufacturer to really take rally racing head on.  Hard to imagine now, while they're taking the car-as-appliance market head on, but all those other Japanese Rally Reps followed the Celica GT-Four to market. The GT-Four wasn't the first Japanese car to be rallied - Mitsubishi rallied some Starions, and Toyota itself rallied Celica Supras as well as the Celica Twin-Cam Turbo (TA64) in Group B.  But the Celica GT-4, based off the new front-drive Celica architecture, was the first to follow the now-familiar front transverse, turbo four-wheel-drive formula.  Previous Japanese rally entries hadn't really set the stage on fire, but the GT-Four was a quite successful competition car, and as a result, a very well-rounded performance road car. The first GT-Four came out in 1986, well ahead of the Celica's WRC debuted in 1988.  Based on the T160 chassis, the GT-Four was internally referred to as the ST-165.  Whereas the normal Celica had a 116bhp 3S-FE or a 135bhp 3S-GE under the hood, the GT-Four used a turbocharged, air-to-water intercooled 3S-GTE.  This was a pretty advanced engine, the 16v aluminum twin-cam head designed by Yamaha, with pent-roof combustion chambers, central spark plug, and a cross-flow intake.  The same engine used in the critically acclaimed 1990-1995 MR2 Turbo, the GTE produced 190 horsepower and 190ft-lb or torque, which were damn solid numbers back in '86.  Remember, back then the RX-7 Turbo was only 185 horsepower, a 5.0 Mustang with it's new fuel injections system had 200, and the Corvette had 230 from it's 350ci motor. Powertrain was four-wheel drive, and '86 GT-Four's had a traditional center diff that was manually lockable.  When the ST165 was updated in 1987 for MY1988, the center diff changed to a viscous-coupling limited slip unit, providing more progressive power transfer than the manually locking unit.  Although presumably less impressive donuts.  The GT-Four hit the US market in limited quanities in 1988, marketed as the All-Trac Turbo, to keep it in line with the rest of Toyota's All-Trac 4WD models in the US.  It was a pretty quick car; weighing in a hair under 3200lbs, Motor Trend tested an '88 All-Trac at 7.78 seconds to sixty and 15.95@89mph in the quarter mile.  The AWD setup gave it plenty of grip, pulling 0.79g's on a 200ft skidpad and just under 60mph in a 600ft slalom test.  Around the Streets of Willow race track, the little Celica was only 1.3 seconds slower than the considerably more powerful Supra Turbo's time - not too shabby. While consumers were enjoying the turbo power and 4WD grip of the ST165 GT-Four, competitors were enjoying winning races in it.  The ST165 debuted at the 1988 Tour de Corse, and it's first race win was the 1989 Rally Australia.  Over it's competition lifetime, ST165's prepared by TTE (Toyota Team Europe) scooped up 13 WRC wins, as well as the WRC Driver's Title at the hands of Carlos Sainz. The T180 generation Celica, with it's curvy soap-bar styling, replaced the T160's in 1989, and the new All-Trac hit US shores in MY1990.  It was largely the same, but Toyota made a series of improvements to make the GT-Four a better-performing car in all areas.  The new GT-Four was based off the wide-body Celica GT-S, which had a wider track width at both ends to fit bigger tires and provide more stable cornering. First of all, there were changes under the hood.  The air-to-water intercooler was ditched (at least in normal GT-Four models, keep reading) in favor of a big top-mounted air-to-air heat exchanger.  The hood was designed to force air through the intercooler.  In addition, the turbocharger was changed to a twin-entry CT26b - technology that's just now coming into vogue today.  Finally, a bump in compression from 8.5:1 to 8.8:1 as well as increased valve lift helped bump power to an even 200bhp and 200lb-ft of torque, along with fattening the curve under the peak for harder in-gear pulls.

httpv://www.youtube.com/watch?v=OzM8NB3ae4M

The suspension and rolling stock was tweaked as well.  The rear subframe was beefed up, the spring/shock axis offset was increased for lower friction, and the the rear control links were spaced out to obtain better cornering stability and toe control.  Wheels were an inch taller and wider (15x6.5 compared to 14x6 for the ST165) and tires were stickier 215/60/VR15's.  Brakes were about an inch bigger at each end, and ABS was optional. Japanese-market GT-Four's were even more powerful than the USDM cars.  With an even high compression ratio and a special ceramic-turbine CT26, they put out 225bhp and 224ft-lb of torque.  Exported GT-4's were all wide body liftbacks, but JDM models could also be had as the more torsionally rigid coupe body.  With the new GT-Four, Toyota spent more effort making it a luxurious car as well as a fast one.  Options included leather seats, a 220-watt 10 speaker "System 10" stereo, an electric sunroof, and other goodies like ABS and fog lights. Performance was improved; Motor Trend tested a US-spec All-Trac Turbo 0-60 in 7.5 seconds, the quarter mile in 15.6@88.3mph, and 0.87 of lateral grip on the skidpad.   The price in 1990?  A hefty $21,500, or $26,400 with options.  Yikes! Big news came for 1991 with the GT-Four RC, limited to 5,000 units worldwide.  This special edition was more than tape and stickers.  The intercooler was changed out for an air-to-water unit, and the hood was switched to vent pressure out of the engine bay rather than push air into it.  (In the picture above, the air-to-water Carlos Sainz is on the left, a regular GT-Four on the right.)  It got a Torsen limited-slip rear differential to compliment the viscous LSD center diff, 2nd and 3rd gear got upgraded synchros and the action was given a short shift mechanism.  Called the Carlos Sainz edition in Europe and the GT-Four Group A in Australia/NZ markets, this special edition offered more reliable performance in all weather conditions - since air to water intercoolers are less prone to heat soak, the bane of all turbo cars. So while the ST185 evolved as a performance road car, it began the era of Toyota's WRC domination.  It captured a total 16 WRC series wins, 3 W2L series wins, and 3 driver's titles in a row - Carlos Sainz in 1992, Juha Kankkunen in 1993, and Didier Auriol in 1994.  Oh, and also the WRC Manufacturer's title in '93 and '94.  Not too shabby for a "chick car." The ST185 was in production until 1993, when it was replaced by the new ST205 model, the one with the quad bug-eye front end.  This model was basically an evolution of the ST185, still using the 2.0L 3S-GTE motor, but had many revisions.  Much like the rare Ford Sierra Cosworth RS500, it incorporated many features (albeit non-functional from the factory) of the race car, for homologation purposes.  The turbo was an updated version of the CT26, still a twin-scroll unit but with a revised compressor, called CT20b.  For the ST205 generation, the intercooler was switched back to water-to-air for it's better cooling properties.  2500 GT-Four homologation models were produced, which had the plumbing installed (but not hooked up, strangely) for an anti-lag system.  There was also (again, unhooked) the equipment for basic water/methanol injection, and a water spray bar to drop intercooler temps.  Power output grew to 239bhp for export cars and 252bhp for JDM vehicles; there was no specified power gain for the WRC/Group A homologation models, as all the cool hardware was present but not hooked up.  I suppose that's up to you. The huge spoiler was mounted on risers, and "super strut suspension," which is a weird mix between a MacPherson Strut and a multilink setup that minimizes or eliminates camber and toe changes under load.  Apparently it had some issues with breaking all the time, because TTE eventually gave up and switched back to conventional McStruts for the GT-Four rally cars. These ST205 Celicas were again an improvement in performance over their predecessors, with Toyota claiming a 5.9 second 0-60 time.  Most publications had trouble replicating that result, most showing 0-60 times in the mid 6's.  Still not shabby.  But many complained it was impossible to launch the GT-Four well; not enough revs and the engine would bog and almost stall, resulting in a slow time.  Too many revs, and the clutch would smoke.  I suppose that's the downside of massive four-wheel drive grip.  The real problem was the price tag; it was considerably higher than the now-faster competition like the Impreza WRX and Lancer Evolution.  Toyota didn't even bother to import the ST205-generation GT-Four into the US, considering they only sold 271 All-Trac Turbos in the US in 1992. The ST205 was improved in a lot of ways over the ST185, so it's mystifying as to why it only captured 1 WRC Series win and 2 W2L titles.  Simple: the WRC governing body sort of noticed that Toyota was cheating, and banned them for a year.  It was discovered that Toyota was using an illegal turbo restrictor plate on the ST205 Celica GT-Four's, and they were booted out of the whole season.  Then Group A disbanded, and that was pretty much the end of the GT-Four. The GT-Four was a car that went from a star to an also-ran over it's lifetime, with cheaper and faster competition on the road, and eventually the class it was created to run in being disbanded.  The Celica GT-Four rally car was replaced with the smaller Corolla WRC to compete in the smaller, lighter WRC class.  The 3S-GTE itself lived on in Japan as the top-line engine offering in the 2nd and 3rd generation Caldina GT-T and GT-Four wagons.  This was a big update of the now-old 3S-GTE, with direct ignition, a turbocharger cast into the intake manifold itself, and many other small differences.  This little wagon (about the size of a US-market Matrix) came with the GT-Four's all wheel drive system mated solely to a 4-speed "tiptronic" automatic, and produced a 7-second 0-60 time with 260 horsepower.  This was the last application of the 3S-GTE before it died out for good, when the Caldina went AWOL in 2007. Still, the Celica All-Trac/GT-Four is a car that history will remember well as starting the whole turbo four-wheel-drive Japanese rally-rep template, long before Subaru and Mitsubishi got in on the game.  Want one?  Good luck!  A nation-wide search of autotrader (as of 12/6/2010) showed up a grand total of three All-Trac's - one absolute beat ST165 at a sketchy buy-here-pay-here lot, one ST185 with 199,000 miles, and one that appears to be a FWD GT-S that's been converted to a tuned 3S-GTE motor. But if you're looking for a Japanese rally-rep that's not another stinking WRX/Evo, give the GT-Four/All-Trac Turbo a look.  If you can find one.