The Toyota Celica GT4 - Part 3

That was a really sad moment for the rally racing world. Especially so because Toyota was one of the most (if not the most) innovating teams around. They, first, introduced hydro-electronic differentials, they introduced the A.L.S. (a.k.a. bang-bang) engine management system as well as the "joystick" gear change interface (in the Corolla WRC) among many other innovations.

Anyway back to the car now, the Celica GTFour was based on the production Celica versions and looked almost exactly like one. The latest street version of the car contained some very fine engineering. The 2 liter 4 in-line engine was derived from the atmospheric (non turbocharged) version and delivered anywhere from 220 Bhp in its first versions to 242 Bhp in the latest street GTFour. Turbo lag time was kept within reason due to the use of a small, in-house, CT-20 turbocharger. Many technical innovations where present in this engine and car. You may note among others:

• An electronically controlled turbocharger (Toyota Computer Controlled System) which also handled injection and ignition
• Specially shaped intake and outlet tubes
• A very cleverly designed two-way catalytic converter which reduced back pressure on the turbo
• A water to air intercooler whose water was cooled in an extra water cooler
• Increased water and oil flows compared to older versions of the engine
• The Fresh Air Intake System, a device producing almost the same effects as an A.L.S. (this was unfortunately disconnected in street cars due to excessive exhaust tube stress and noise)
• 4 piston aluminum brake calipers in the front wheels and 315!mm vented brake discs
• Many parts of the body where in aluminum including the engine bonnet, parts of the chassis, etc.

The specification of the street version ST205 Celica can be found here. As you might have already guessed this was some car. Toyota delivered more in the Celica GTFour than one could hope for. The Torsen (which stands for Torque Sensing) rear differential was a very good surprise too. Previously used in the Lancia Integrale and the Audi Quattro this device generates extra costs to the overall price of the car. No wonder the Celica GTFour was the most expensive street versions of the homologation specials. The one problem the street Celica version was suffering from was its weight. A laden weight of around 1450Kg is way too high for a "sports" car and generates important inertia-induced parasitic movements. This fact influenced badly the car's handling abilities.

Even more technology was packed in the competition version of the Celica GTFour. You see Toyota really wanted to win the WRC title. Rally used to be a very important part in Toyota's marketing budget at the time. The team hired two of the most talented rally drivers ever: Juha Kankkunen and Carlos Sainz and invested huge amounts of energy and money to beat the Lancia Integrale, at first, then the Ford Escort RS Cosworth and finally the Subaru Impreza. They managed to succeed.

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