Toyota Corona 1600 GT

Introduction

In 1967 in Japan, the 1587cc DOHC 9R engine was available in the RT55 1600GT 2-door coupe. This engine was essentially the 4R engine with a new twincam head based on the same technology as the twincam engine in the 2000GT. This was the first Corona assembled in New Zealand, from February 1967 at Steel Brothers' Motor Assemblies in Christchurch.

By the time the 1600 GT hit the road, Toyota’s efforts to deliver itself into the performance car field were rapidly becoming faster and more convincing. They had gone well beyond the stage of simply screwing on another carburettor and raising the compression ratio. The 1600GT may have had strong two-door Corona overtones but under the elaborately finished skin there was virtually nothing remaining that tied it to the Corona family.

First production models rolled out in August initially for the home market, but Australian Motor Industries got one of the first export cars for evaluation. A handful of lucky motoring journalists got to drive the car in both wet and dry conditions, and it turned out to be a more convincing product than any had anticipated. As far as they could tell, there had been no half-measuring anywhere along the line, either in the handling or the performance.

The Heart of the Beast

The heart of the beast, of course, was its twin overhead camshaft four-banger. It used the same basic 1587cc block that went into the 1600S Corona sedan. However, there was some additional machining to the block to take the cam-drive train and stronger bearing caps were used to stiffen the three bearing crankshaft. Of aluminium alloy, the cylinder head wore its valves at 39 degrees, with a 9 to 1 compression ratio and thumps the fuel into its twin double-choke Solex-Mikuni 40 mm carburettors with an electric pump.

Externally, the head was a shorter edition of that used for the 2000GT. Both were developed by Yamaha, then known as the electric organ and motorcycle people, but these days synonymous with outboard engines, quality hi-fi gear and a wide range of musical instruments. Coupled to the optional five-speed 2000GT gearbox, the 1600GT engine gave a good account of itself on the road. However, with its 110 (SAE) bhp coming in at 6200 rpm plus 101.3 ft/lb of torque at 5000 rpm, the four speed gearbox didn’t provide enough ratios to make the best use of the under-bonnet happenings.

On the Road

Absolute maximum engine speed was stated in the owners manual as 7200 rpm. As you can imagine, the Toyota had a very pronounced cam action. The car accelerated well enough from around 2500 rpm, but the fire-power really made itself felt at about 4750 rpm. In its own way the engine had quite an on-off character. Even with the 4.1 final drive fifth gear would take the vehicle along smoothly enough at 25mph. In other words, the tiger was there right enough, but not demanding frequent de-caging. Once the engine got up on the cams, it accelerated very quickly so that it was vital to keep a close watch on the 9000 rpm tacho to avoid exceeding the limits.

A full flow oil filter and a high speed oil pump were adopted to cope with the lubrication demands. What's more, the heavily-baffled sump was forged aluminium alloy for rapid heat dissipation and all the plumbing was in place for the installation of an oil cooler, recommended if the 1600GT was used for competition work. Roadholding and handling was better than any of the road testers had expected, but it was achieved at the cost of a firm ride at low speeds. Basically, the suspension was the same as it was on the Corona; independent coils at the front and wide semi-elliptics at the back. The springs were re-rated and shockers were set-up to cope with the high speeds of which the 1600GT was capable. Twin torque rods located the back axle in much the same way as they did in the Cortina GT. It was possible to be pretty reckless in handling the GT without it getting even slightly twitchy. The torque rods did a proper job, too, especially on rough corners.

On the Inside

The cabin was very realistic and beautifully equipped and detailed. The facia had all the gauges and dials that mattered, inclusive of a sporty steering wheel and gear shifter. There was an effective heater/demister, radio with power antenna, through-flow ventilation, clock, screen washers, safety belts and so on were all standard equipment. The seats were supportive and comfortable – well above the standards set by other Japanese cars from the time. Like the gearbox, they came from the 2000GT. Superbly styled, they were very generously dimensioned and extremely comfortable despite a certain firmness. A direct competitor with the Alfa Veloce on some scores, the Toyota appealed to a different segment of the market. It did not seem to go as hard as the Alfa, but was cheaper and certainly better equipped.