The full conversion also includes lightening and balancing of all rotating parts, a special oil pump and an oil cooler. The suspension is basically unchanged, although a rear anti-roll bar and adjustable telescopic shock absorbers are fitted. The supplementary instruments mentioned above are also included in the conversion, which is marketed at £240. Alternatively, Speedwell offer a road going version of the same conversion, costing £195. The main differences are that on the road tuned car there is a lightened production flywheel, giving a 23 per cent reduction in moment of inertia, and the work on the bearing caps, hand selection and machining of rods, and final finishing of the cylinder head is not taken quite so far.

Ken Lee's Cooper Mini is run on Castrol 'R', and as regular competitors will know, this calls for a carefully controlled starting procedure. The Amal air slide is fully closed, the starter operated, and the throttle opened up very slowly. As soon as the engine fires, the lever is moved to the half-way position, and the engine is allowed to warm up at 2,000 rpm. The racing oil being thick, the oil pressure takes some time to build up, but as soon as it reaches about 40 psi the engine can be opened up. About a mile of running is necessary from cold before the air lever can be opened completely, and from then on it will not be needed for the rest of the day, unless the engine is restarted after several hours in around zero temperature.

The big advantage of boring out, of course, is that it gives the opportunity for a lot of extra performance to be obtained without making the car unpleasantly intractable. In this case, although peak torque is not obtained until 5,000 rpm, the pulling power necessary for normal road use is available as low as 2,000 rpm, or even lower, so that the car can be driven in heavy traffic just like the standard production car, with the possible exception of a higher tick-over speed.

Not surprisingly, prolonged low-speed running results in some fluffiness when opening up again for the first time, but usually this soon clears, and the engine regains its usual crisp note. On two occasions, however, a plug was 'lost'. The first was after a really hectic traffic jam, and the other was due to inadvertently over-filling the sump when topping up with 'R'.

Pleasantly surprising, was the subdued exhaust note when the car was being driven normally; it it only when the needle is pushed beyond the 4,000 rpm mark that something of a bark accompanies the sweet-smelling exhaust cloud from the tail pipe. Even though the test included a lot of high speed driving, the oil consumption worked out at close on 200 miles to the pint. At very low speeds, the separate firing impulses could be detected, but once under way the engine gave no hint that it was running on such a high compression-the value of a light alloy head. There was a rough patch from about 3,200 to 4,000 rpm, which was transmitted through the gear lever in the form of a violent rattle, and this was probably due to the fact that the engine had had to be stripped and rebuilt very quickly between events, and there had been no time in which to regain the former balance.

Beyond this mark the unit was much smoother, right up to peak revs. Quite a careful watch has to be kept on the needle at the top end, because the punch between 4,000 and 7,000 rpm is surprisingly good. Fortunately, there is a considerable build-up in mechanical noise beyond 7,000 rpm, and this is a useful warning that it is time to change up! Speedwell recommend that 7,500 rpm should be used only momentarily, and although the engine still sounds in good shape then, I found that there was no real point in pushing the needle beyond 7,200 rpm. Using this limit, the top speeds in first, second and third gears are 36, 60 and 84 mph, which seems useful enough by any standards!

A reasonably long stretch of clear road will allow 6,500 rpm to be seen in top gear, and this corresponds to just under 104 mph, while with the aid of a slightly favourable grade I saw 6,800 rpm which is no less than 109 mph I might add that the road surface was not completely dry for this, or for the acceleration runs, and in perfect conditions a slight improvement would have been likely. The comfortable engine speed for sustained cruising seemed to be about 6,000 rpm, or just a little more, which is not so very far short of 100 mph. (Top gear speed at 1,000 rpm is 15.9 mph).

Naturally, more than usual care must be taken with the Mini when using very high speeds, in view of the ten inch diameter wheels, and the tyres (Dunlop C41s with tubes were fitted for the test) should never be run below 40 psi for fast motoring.

Being a dual-purpose car, the suspension settings had not been changed, and undoubtedly track performance would have been enhanced by lowering the suspension the full amount. But this would have resulted in an uncomfortable road car, so Ken Lee's compromise is probably the best one in the circumstances. With an inherently understeering car, an increase in engine power can only serve to exaggerate the understeer. The rear anti-roll bar has helped somewhat to keep this within reasonable limits, but I noticed, particularly on a wet track, that the right foot has to be played very delicately on sharp bends if the car is to be kept on line. When it is really slippery it is possible to put on lock, then travel in a zig-zag simply by playing with the throttle!

On public roads, and driving in a rather more restrained fashion, the car handles very well indeed, and it is a delight for a really fast cross-country journey through twisty minor lanes. The technique for this seems to be to let engine power build up the understeer slightly, then steer accordingly, so that if you have to lift off the car will automatically tighten its line. On right-hand bends, this can be countered by taking off lock, while on left-handers, it automatically pulls you close in to the side. The disc and drum brakes were well able to cope with the car's speed, and the only complaint on this score was that the discs persisted in squealing, especially when they had become hot. Not a very comforting feature for pedestrians close by!

Apart from the gear lever rattle, the gear-box was in fine form after its season's hard work, while the clutch still had a light action, and a quick release, which even enabled bottom gear to be selected cleanly when moving slowly.

This is a remarkable little motor car, and as a fun machine it must have few peers at the price. Ken Lee has proved that, as long as you are happy to concentrate on the smaller type of event, your commuting transport can also be a competition class winner a workhorse one day, a plaything the next, and the source of a lot of enjoyment all the time. Viva Group 3!

JOHN BLUNSDEN