A 100 m.p.h. 4-seater G.T. car sold in component form for £945
How many 4-seater G.T. cars capable of 100 m.p.h. and costing under £1,000 can you name? Precious few; and those that do fall into this category are invariably normal saloon cars such as the Lotus-Cortina. In fact since the demise of the Warwick G.T. and Tornado Talisman the ranks of high performance 4-seaters selling at a reasonable price have been very thin indeed. However, one such car does exist – the Gilbern G.T.
The Gilbern was described in our issue of June 1963 when we visited the factory near Pontypridd in Wales, so suffice it to say that the car has a multi-tubular steel chassis of square section tubing with most of the running gear taken from the M.G.-B. The front suspension is stock M.G.-B with suitable spring rates while the M.G.-B rear axle is well located with twin radius arms and a Panhard red and is suspended on Woodhead Monroe coil spring/damper units. The same brakes as used on the M.G.-B are fitted, these being Lockheed 10 3/4 in. discs at the front and 10 in. drums at the rear while the M.G.-B 14 in. wire wheels are used in conjunction with Dunlop RS5 tyres. The rack and pinion steering of the M.G. is used. The M.G.-B 1,798 c.c. engine, giving 96 b.h.p. at 5,400 r.p.m. is fitted in standard form together with the 4-speed gearbox which is available with overdrive.
We have recently been testing a production Gilbern fitted with overdrive and found it to be a most interesting car to drive. As it is mechanically M.G.-B its performance is very similar although its greater frontal area reduces its acceleration times and top speed over those of the M.G. However, the M.G.-B we tested had no overdrive and as the engine of the Gilbern was rather tight exact comparisons are difficult. All the same, a 0-60 m.p.h. time of 13.5 sec. and a standing-start 1/4 mile in 18.9 sec. are quite acceptable for a car of this capacity. In the upper speed ranges the car tends to run out of power at just over the 100-m.p.h. mark. It will reach 6,000 r.p.m. in overdrive third, a speed of 100 m.p.h., 5,500 r.p.m. in top gear which is also equal to 100 m.p.h., and in overdrive top will touch 4,600 r.p.m. at 104 m.p.h. The theoretical top speed of the car at 6,000 r.p.m. in overdrive top is 135 m.p.h., but it will need a good deal more power to get anywhere near this speed. We have driven a privately-owned Gilbern with a tuned 1.6-litre M.G.-A engine which showed a speedometer 120 m.p.h. and it seems likely that a reasonable sum of money spent on tuning the M.G.-B engine would see a top speed of 115 to 120 m.p.h. Since this is intended as a 4-seater touring car its ability to travel all day at 4,500 r.p.m. in overdrive top at a comfortable 100 m.p.h. is more important than the ultimate in top speed. Gilbern do offer as an extra an aluminium cross-flow cylinder head with twin Weber carburetters and we have arranged to test a car fitted with this equipment in the near future. However, for all normal purposes the acceleration is very satisfying and the typically low B.M.C. 1st gear ensures a good getaway as well as having a maximum speed of 30 m.p.h. 2nd gear is good for 50 m.p.h. and 3rd for 80 m.p.h., using a 6,000 r.p.m. rev limit.
The engine is set well back in the frame to give good weight distribution but sound insulation has obviously been well carried out, as the engine is comparatively quiet, except when revving hard. It has the typical B.M.C. “tappety” sound at idling revs but is generally smooth in operation and has excellent torque over the 3,000 r.p.m. mark. On the test car there was a vibration period between 75 and 80 m.p.h., but the car passed through this and the only other vibration or undue noise occurred when the engine was running at peak revs. The rearward mounting of the engine means that the gearbox is well back in the chassis but the gear lever has been bent forwards and it is now in just the right position. The gearbox is quite pleasant to use and the change from 2nd across the gate to 3rd can be snatched through very rapidly without heating the synchromesh. 1st gear is unsynchronised and was occasionally difficult to engage, but the Gilbern moves off quite happily in 2nd without judder. Reverse is engaged by pushing the gear lever against a strong spring beyond 1st and 2nd gear positions. The clutch is reasonably light to operate but as the pedals are offset to the right to clear the engine the driver’s left leg does tend to ache if the clutch is held out for any length of time.
The brakes are well able to cope with the performance of the Gilbern and although a good hard push is required to haul the car down from high speeds this results in excellent reassuring stopping power. As the pedal is offset to the right the driver is unable to give a straight push, but this is only of initial annoyance. Heel-and-toe gear changes can be made quite comfortably.
The front bucket seats are made from glass-fibre by Gilbern and are excellently shaped and well padded. The rake of the backrest can be adjusted quite quickly by removing the hinge bolts with a spanner and re-locating the backrest. The range of fore and aft adjustment must be among the greatest to be found on any car and with the drivers seat on its rearmost stop, a 6 ft. driver could barely touch the pedals. Not unnaturally, this reduced the leg room in the rear bench seat to negligible proportions, but with the front seats in a mid-way position two medium-sized adults could sit in the rear. Taller occupants would probably be cramped and their heads would touch the roof. Access is gained by tilting the front seats forward.
On initial acquaintance in town the ride of the Gilbern seems rather hard, but as speed builds up on the open road the ride smooths out and becomes very pleasant. It is still quite firm by present-day standards, but is hardly likely to bother anyone. Directional stability is excellent and none of the usual impediments to straight-line running, like cat’s-eyes or dividing white lines, upset the car at all. Up to around 80 m.p.h. wind noise is commendably low, and the radio can be heard on low volume, but near its maximum speed there is a fair amount of wind noise, due mainly, on the test car, to an imperfectly sealed side window. It is certainly a very much quieter car than the M.G.-B.
The rack and pinion steering is rather heavier than we have come to expect from this system which can make the arms-stretch type of driving position a little tiring when cornering hard. However, there is little of the kick-back normally associated with rack and pinion layouts and with three turns lock-to-lock, the steering is pleasantly precise. A wood-rimmed steering wheel is standard but the one on the test car had a rather sharp edge which was rather unpleasant. The handling of the Gilbern is quite straightforward and uncomplicated. It understeers right the way through the speed range until the rear end loses adhesion, but instant movement of the high geared steering brings the car back on to line with no drama. There is very little roll noticeable and the Gilbern is capable of high cornering speeds in complete safety. The Dunlop RS5’s grip very well and refuse to squeal even when pressed very hard indeed. It seems that the front suspension is stiffer than that at the rear as the inside rear wheel would sometimes lift on tighter corners.
The petrol tank of the Gilbern holds 9 1/2 gallons, filled through a lockable filler in the offside rear wing. With much hard driving and prolonged performance testing the fuel consumption worked out at 22.4 m.p.g., which is much the same as the M.G.-B. In more normal driving we would expect to achieve 25 m.p.g. with ease. Even at the lower figure the car will cover well over 200 miles before refuelling is required, although on the test car the gauge seemed rather out of tune with the contents of the tank.
A major problem with kit cars of this type is the standard of finish and fitting of various components. This has largely been overcome on the Gilbern and the standard of finish is very good indeed. When the car is purchased in component form it comes in a very advanced state of completion and generally the car can be assembled over a weekend. One car we know of was completed on a Saturday morning.
Realising the poor tensile strength of glass-fibre, Gilbern have designed the body to be merely a shell to keep out the weather, which has no part to play in the stiffness of the chassis. The boot lid, doors and bonnet are all hinged on the chassis and the locks all worked perfectly, a sure sign that the doors had not dropped with use. Double skinning is used extensively so that when doors and lids are opened no ugly mess of straggling glass-fibre can be seen. The body surface is very smooth and the paint finish reaches a high standard. The shape of the body did not appeal to everyone who studied it, but it is extremely difficult to obtain a sleek G.T. shape and still retain room for four passengers.
The interior finish is extremely good with well upholstered seats, P.V.C. covered door panels, carpeted floors and a padded facia. Instrumentation is quite lavish comprising speedometer, rev.-counter, fuel gauge, electric clock, ammeter, water temperature and oil-pressure gauges. Warning lights are incorporated for headlamp main beam, dynamo charge, and direction indicators. A row of identical toggle switches in the centre of the facia control lights, 2-speed windscreen wipers, washers, heater blower fan, panel lights and the fog and spot lamps. The last two are extras, costing £7 19s. 6d., as are the heater which costs £17 10s., and the electric washers, costing £4 5s. The overdrive switch is on the extreme right of the facia and the winkers switch is on the right of the steering column. This switch is also used for daylight flashing of the very powerful Lucas Le Mans headlights, which are streets ahead of the normal Lucas lamps. The test car was also fitted with a Motorola radio costing £28 19s. Small lockers are provided in the facia and both doors, while a large flat space behind the rear seats can be used for stowing flat items which do not impede rearward vision. Twin, softly padded sun visors are fitted, an ashtray is mounted on the padded central tunnel and the rear passengers have large arm rests. The two doors have metal pulls, winding windows with a rather poorly located handle and non-opening quarter-lights. Ventilation is provided by the fresh air heater or by the two unframed rear quarter-lights which can be held open with over-centre catches.
The small boot is lockable and has the spare wheel lying fiat on the floor, together with the jack. This reduces the available room quite considerably but two reasonable sized cases can be carried. The lid, like that of the bonnet, has to be propped open.
We spent a very pleasant week with the Gilbern, for it showed that cars built for home assembly need not be rough, noisy and badly finished. Indeed, it would be very difficult to distinguish the Gilbern from many factory-built products. It offers a comfortable 100 m.p.h. cruising speed, four seats, high standards of handling and braking, and can be serviced by any M.G. agent. At £945 in component form, or £1,184 7s. 10d. assembled, with Purchase Tax, the Gilbern is well worth considering. Details can be obtained from Gilbern Sports Car (Components) Ltd., Pentwyn Works, Llantwit, Nr. Pontypridd, Glamorgan, or from their London Agents, Ace Motor Co., 20 Radley Mews, Kensington, W.8, who loaned us the test car. – M. L. T.