mm SUPPLEMENT No.4 CONTENTS

Sees Ramblings 1

Autocars Twin Cam Road Test 1-3

My Dream to Realism 4

A Bit of Bad, then the Good News 4

Secs Ramblings This Supplements main feature is the 'Autocar' Road Test of the Twin Cam, which was con- ducted mainly on German roads, using YD1.524 (see last month's notes) during July 1958 and was published the following month.

The supporting items both come from North American owners of very early cars, which seems reasonable as most of these were ex- ported there.

We should record here the great success of the 1983 Silverstone 25th Anniversary celebra- tions, and at the same time the disappointments which were the lack of poster and booklet that were promised. The latter was postponed deliberately because we found the large effort and long lead in time with everything else going on was going to be impossible to achieve. The former project was well in hand and contract placed with the printer with agreed completion date. On that date enquiring of the time to collect the printer advised he had not even started thf job. When the Group's accounts have been balanced in consideration of the whole Silverstone project more monies should be available to produce an even better poster than was at first thought possible. So hopefully out of this disappointment a greater satisfaction will ultimately result. I think we might have found a better printer as well.

AUTOCAR ROAD TEST - 1692 M G TWIN CAM MGA Open Two Seater By producing a high performance model to partner the successful MGA two-seater, the MG Cat Company Ltd., has filled a gap which has been evident to overseas and competition minded motorists; the new 1588cc Twin over- head camshaft engine will enable the car to compete on equal terms in the 1300-1600cc class with Continental built cars. As described in preceding pages, this engine is a develop- ment of the special power unit used in the record breaking MG EX181.

The new model also has Dunlop 103/4" disc brakes, centre lock steel wheels and Road Speed tyres, which are not fitted to the standardMGA. The road test car was an open model equipped with hood and side screens and all optionally extra equipment. A coupe version of the car is available.

Powered by the twin carburettor version of the 11/z litre B series engine, the standard MGA coupe is capable of slightly more than 100 mph, the new 16OOcc unit gives the open car, with hood and side curtains in position, a maximum of 114 mph. It is faster than the 1V2 litre car by 1.7 sec. to 60 mph, and by 15 sec. to 90 mph.

The engine starts easily and quickly reaches working temperature. It revs freely, and the limit marking on the tachometer is 7000 rpm; it was taken up to this limit repeatedly during the test.

Engine vibration was noticed at 2500 and

5500 rpm; at maximum speed in top gear the tachometer reading was 6500 rpm, and this was held for approximately 5 miles on a level stretch of autoroute.

Power builds up noticeably after the engine tops 3500 rpm; by the time 4000 rpm is reached it really takes hold and the little car begms to show its potential performance. In first gear it gets very quickly to 30 mph, and a fast change to second gear is needed to avoid exceedmg the rev limit. The comfortable minimum speed in top gear is 18-20 mph, and in traffic, second and third gears are most used. In open road cruising, 80-90 mph can be held indefinitely, with plenty in hand for use when required. The car was quite happy at 100 mph for long stretches on Continental roads, although to maintain high engine speeds has marked effect on the fuel consumption, of course, and above 90 mph the driver has the feeling that the engine is working much harder.

There is constant, rather obtrusive background of mechanical noise; most of this can he traced to the valve gear, particularly the tappets, which have a recommended clearance of 18 thou., but there is also a 'ring' associated with the first stage of the timing gears. Nor can it be said that the engine is smooth or silky. Exhaust wise, the car is not objectionable, and it can be driven through city traffic without

Thisisbelieved to be Roy Perkins with the ex-John Gott car YD1.652 a t Silverstone in the early 70s. It is rumoured that the present owner lain Gerrard i s about to start the cars rebuild, not just because the loft rafters are collapsing.

Twin Cam Group Supplement SAFETY FAST, October-November 1983 19

MikePryce, shown here at the 1982 Silverstone in hisregularly usedroadster YD1.758. What a super badge he has on the front.

attracting undue attention. This car had a loose silencer baffle. Carburettor intake noise is not noticeable, although only small flame trap type air cleaners are fitted.

From the performance and maintenance angles, the I.̂ GA has an enthusiasts engine. Many of the anci!lary units are not easy to reach, as the underbonnei; space is filled by the engine itself. The distributor is located below a cam- , shaft housing (it became covered in oil during the test), and the coil is tucked away under the heater trucking. The oil level dipstick would be easier to replace if its containing tube were a little longer. An oil cooler, which is an optional extra, was mounted ir. front of the radiator, but no oil temperature gauge was supplied.

All maximum speed and acceleration tests were carried out with 100 octane petrol. With this, the Belgian premium petrol (89 research octane rating) the engine tended to 'runon' after being switched off. It also used a considerable amout of oil; five pints were added to the sump during one journey of 800 miles and an overall oil consumption figure of 1020 mpg was recorded approximately one quart of oil each time the petrol tank (capacity 10 gallons) was refilled.

Once accustomed to the controls, an experi- enced driver can get off the mark with little wheel spin, but it was felt that more suitable gear box ratios would give an even more sparki- ing getaway, without losing the benefit of easy fast cruising - there is a very noticeable inter- val between first and second, and between second and third. An owner using the car for cir- cuit racing would, no doubt, prefer a gear box with closer ratios. A 4.55:l axle ratio can be fitted in place of the standard 4.3:l at an extra cost of E10.2s.6d.

Apart from the occasionaldifficulty m select- ing first gear when the car is stationary, the gear box is generally pleasant to use. The short, remote control lever has precise movement between the ratios, and very fast changes can be made. One notices a slight difficulty not uu- common in B series gear boxes - in getting through the gate transversely, particularly when the gear box is hot. This sometimes makes difficult the change from third to second, and there is a risk that the lever may overshoot into the reverse quadrant. The top of the gear lever is close to the steering wheel when the latter is set near the facia; it is also well placed in relation to the driving seat. There was no vibration from

the transmission, and the axle was silent. Free from slip during full-bore gear changes,

the clutch transmitted the engine power with- out judder under all conditions. Some adjust- ments were'found necessary to take up pedal movement, but once attended to the need did not recur. Positioning of the pedals is good, although to clear the clutch pedal, the left foot has to be placed beneath it rather than to the left. The accelerator, which is connected to the throttle by a cable, works smoothly, and delicate progressive control can be achieved.

Among the most delightful features of the MGA are its road holding and cornering. The manufacturers well known motto - Safety Fast - is particularly pertinent to this new model. Changes in road surface have little effect on the manner in which the car sits firmly on the road, and its behaviour on a streaming wet road is quite good, although the tail willswing slightly if the throttle is opened suddenly when cornering. Power can be used judiciously to help the car round a corner, in fact progress on a winding road is all the better if this technique is applied.

There is strong centring of the steering, and there is no lost motion to impair its accuracy; from lock-to lock requires only Z3/4 turns of the wheel, and although the turning circle is greater by 4ft 6 in that that of the 1% litre engined car, the Twin Cam model can be manoeuvered eas- ily in narrow streets.

A slight heaviness in the steering was noticed with the tyres inflated to the normal re- commended 18lb front and 201b rear; when pres- sures were raised by 4lblsq.in. this heaviness disappeared and the ride was not uncomfortable.

With full load, or with the driver only in the car, there is a satisfactory firmness about the suspension, which reaches an excellent com- promise in a car which may be called upon to take the owner to work during the week, and yet he driven in races at the weekend. Stability is first class and there is no heeling over on cor- ners, although brisk progress is marked by ex- cessive tyre squeal; the latest pattern Road Speed tyres were not fitted to this test car.

The driving position is well suited to most drivers, but a person of small stature would be happier with a higher seat cushion. The steer- ing wheel can be set close to the facia, by a lock- nut and bolt fitting, in this position of adjust- ment the driver has fingertip control of the horn button and indicator switch. The thin rimmed wheel is set at an ideal angle for control being almost vertical; it does not obscure the instru- ments.

Fitted to the test car were the competition type seats, which have a padded roll round the edge of the back rest and long cushion, they proved most comfortable and provided firm sup- port at a good angle. Driver and passenger are well held when cornering fast, and long dis- tances can be covered without fatigue. The pro- ximity of the engine and gear box can bring about an uncomfortably high temperature around the legs and feet. It is probable that own- ers in hot climates will call for separate fresh air ventilators. On the other hand, the warmth would be appreciated in winter conditions.

All the advantage which this car affords for fast motoring would be wasted if the braking system was not up to the same standards. It is becoming increasingly the practice for 100 mph cars, whether they are large saloons or agile two seaters, to be fitted with disc brakes. The Dun- lop lO3/4in. diameter discs fitted to the Twin Cam MGA are adequate to all they are called upon to do in wet or dry. The pedal has a good feel to it, being neither spongy nor too hard,

Ian Bowen 'S car YM1.2062 has been owned by him since 1968 and looks here in very good shape.

20 SAFETY FAST, October-November 1983 Twin Cam Group Supplement

though loads are rather high in normal traffic stops; this is normal with discs, which have no self servo effect, and is noticeable when there is no external servo assistance, as in the case of the MGA. Maximum braking brought the car to a standstill all square, and the brakes could be applied hard when the car was being driven fast on wet roads. There was no noticeable increase In pedal travel after 800 miles of fast driving. The front discs did show signs of scoring, which has not been noticed on other cars.

The parking brake is controlled by a fly off

In the road test of the 1% litre MGA coupe it was stated in the summary that the car was cap- able of holding its own against more powerful vehicles. This applies even more markedly to the 1600cc. Twin Cam model. The extra perfor- mance is matched by the road holding, steering and brakes, and this car maintarns the MG tradi- tion of good looks coupled with a very fine per- formance.

pattern lever, in which the button is pressed to lock the brake on. The lever is placed between SPECIFICATION the transmission cover and the driving seat, and the hand falls readily on it.

At night reasonable use can be made of the cars performance, although more powerful head En-ne

lamps would be appreciated for speeds close to NO. of cylinders l00 mph; the dipped beam did not inconveni- ~ ~ ~ ~ & ~ t ~ ~ k ~ ence oncoming traffic. The Twin Cam MGA is Displacement one of the cars which really do require a hand valveposition dipper switch. When driving on the open road at Compression Ratio night, one needs two left feet to operate the ~ ~ ~ b h ~ ( ~ ~ t t ) clutch and foot dipper, for the driver always ~ ~ ~ b ~ ~ ~ ( ~ ~ t t ) seems to need to change gear and alter the light Max torque (nett) setting at the same moment. The positioning of Carburettors the pedal and switch are such that the ~ ~ ~ l p ~ ~ ~ changeover cannot he made on the instant. ~ ~ ~ k ~ ~ ~ ~ ~ i t ~

Facia instruments are well lit, and the switch sump capacity is fitted with a rheostat. There is a small map light, with separate switch on the left side of the OilFilter facia. Self parking wipers are fitted, and al- Coohgsystem though they are powerful and silent, they are up Batten, against an unusual handicap - in heavy rain, water is blown off the bonnet on to the screen and the wipers have difficulties clearing it. An Transmission owner could perhaps prevent this by fitting a clutch shallow perspex deflector across the bonnet to Gear box deflect the air stream up and over the screen

With the hood and side curtains erected, the overd car proved weatherproof except at speeds over 90 mph when wind pressure tended to lift the FlnalDrlve hood above the middle of the windscreen rain found its way in there, and also through the scuttle on to the passengers legs. Although Chassis there were gaps between the windscreen frame and the side screens, rain did not penetrate here The hood is comparatively simple to erect and can be folded away neatly behind the seat backrests A plastic bag secured to the body- work behind the seats provide stowage for the side curtains

Brakes

Disc dia. Pad width Suspension: Front

4 in line 75.4x88.9mm (2.97x3.5in) 1588cc(96.91 cu. in) Twin O.H.C. Hemispherical 9.9:l Combustion chamber 108 at 6700 rpm 1631b.sq.in. at 4500rpm 1041b.ft. at4500 rpm Twin 13/-iin.dia. SU Type H6 SU High pressure 10 Imp. Galls (37.8 litres) 12pt. max. 7%pt. min. (5.71 max. 3.61 mm.) Full flow Pump, fan & thermostat 12volt, 51 ampere hour

B&B 8in single dry plate 4 speeds &reverse, sync on top 3rd & 2nd central lever Top4 30.3rd5 91.2nd9 54, 1st 15 65, reverse20 47 1 Hypoid bevel 4 3 1

Dunlop disc, hydraulic operation, mechanical calipers for handbrake lO%in. oldia on rear 2% X 171% in. Ind. coil springs and

With the hood and side curtains erected, a wishbones

tall driver has no difficulty in getting into or out Rear Live axle, half elliptic leaf

of the car, and there is ample headroom. In this springs

condition, the occupants find the interior rather Dampers: Front Armstrong in unit with

warm, and it is not possible to obtain a flow of wishbone pivots

cool air through the vent above the gear box Rear Armstrong lever arm,

cover A heater part of the extra equipment chassis mounted

proved amply efficient in the moderate tempera- Dunlop centrelock

tures encountered during the test. Tyre size 5 . 9 0 ~ 15 in, Dunlop RS4

Accomniodation for maps and small articles Steering Rack and pinion is provided by a deep pocket in each door, but as Steering 16'/2in. dia. Woke the doors cannot be locked, it is not advisable to Turns, lockto lock

stow valuables in these pockets if the car is left unattended. Only the Twin Cam models and the ~ i ~ ~ ~ ~ i ~ ~ ~ 1% litre coupe are supplied with a leather co- vered facia. A large proportion of the luggage Wheelbase 7ft loin (293cm) compartment is occupied by the spare wheel Track:Front 3ftll.gin(121cm) and tool kit, and it is not easy to find room for a Rear 4ft 0.87in (124cm) large suitcase, but a number of small bags and Overalllength 13ft (396cm) boxes can be stowed away. If coats and soft Overallwidth 4ftlOin. ( 1 4 7 4 travelling bags are fitted in carefully, more can Overall height 4ft2h. (127cm) be carried than at first appears likely. Ground clearance Gin. (15cm)

The tool kit includes a starting handle and, Turning circle 31ft 4111. (9.55m) surprisingly, an old fashioned, screw-type lifting Kerb weight 21561b. (1g1/4cwt 977kg) jack. Two 6 volt batteries are located just for- ward of the rear axle, to service them the spare performance Data wheel and a panel in the floor just behind the seats must be removed. The high pressure elec- Top gear mphIlOOO rpm 17.3 tric fuel oumu is close to the batterv on the rioht Torauelb.ft/cu.in. cauacitv 1083 . . . , side of the frame Nine lubrication points require Brakcsurfaceswcpt by linings '194 Esq. m grease qun attermon every 1000 mile:; Weight distribution (dry) F-54 6%

PERFORMANCE

Acceleration

Speed range, gear ratios and time (secs). M.P.H. 4.30:l 5.91:l 9.521 15.65:l 10-30 4.5 3.3 20-40 11.0 7.1 4.5 -. 30-50 10.2 7.4 4.9 - 40-60 10.5 7.5 - -

50-70 11.7 7.6 - 60-80 11.7 8.9 - 70-90 13.6 - 80-100 18.7 -

M.P.H. 0-30 ....................... 0-40 ....................... 0-50 ....................... 0-60 ....................... 0-70 ....................... 0-80 ....................... 0-90 ....................... 0-100 .......................

Standing quarter mile, 18.6 secs

secs 4.3 6.9 9.4 13.3 17.3 22.5 30.0 41.1

Maximum speeds on gears

Gear M.P.H. K.P.H Top (mean) 113 5 182.7

(best) 114.0 183.5 3rd 86 138 2nd 53 85 1st 32 51

Tractive effort

Pull (lblton) Equiv. gradient TOP 232 l in9.6

Third 315 1 in7.0 Second 486 l in4.5

Brakes (at 30 mph in neutral)

Pedal load Retardation Equivstop dist. (lb) (Ft) 25 0.45g 67.2 50 0.62g 48.7 75 0.8lg 37.4 90 0.92g 32.8

Fuel Consumption (mpg at steady speeds)

M.P.H. Direct top 30 42.4 40 40.0 50 35.6 60 31.7 70 27.4 80 23.6 90 20.2 100 18.1

Overall fuel consumption for 1117 miles, 21.8 mpg (12.9 litres/km). Approximate normal range; 18-30 mpg (15.7-9.4 1itresIlOOkm). Fuel: Super premium

Test Conditions

Weather: overcast, raining, slight breeze, accel- eration and braking tests on dry surface. Air temperature 55-65 deg. F. Acceleration figures are the means of several runs in opposite direc- tions. Tractive effort obtained by Tapley meter.

Speedometer correction M.P.H.

Car speedometer 10 20 30 40 50 60 70 80 90 100 110 114 Tme speed: 11 20 28 38 48 58 69 80 91 101 112 114

Twin Cam Croup Supplement SAFETY FAST, October-November 1983 21

My Dream to Realism Carl Ahlberg & YD3.509

I wish to thank you for your letter. First I must apologise for not writing sooner but I tend to procrastinate on letters that are longer than a few sentences.

I bought my MGA Twin Cam around 1967 having owned a 1960 MGA and a 1963 Austin Healey before.

At the time I took delivery of the Twin Cam I was 20 years old, obsessed with Grand Prix racing and sports cars, thinking that it would not be too long before I would be asked by Team Ferrari or Lotus to join them, I had better try and develop my driving skills. Well for two years the Twin Cam was my car for daily transportation and vacation trips,

In the two years that I drove the Twin Cam I matured a bit and became more realistic. I signed up with a college to take Electronics, leaving my dreams of becoming World Driving Champion behind.

In 1969 while out on a shopping trip tragedy struck. I was doing about 60 mph, when sud-

A Bit of Bad, then the Good News Jeff Fishel of Pennsylvania

Thank you very much for your letter about my Twin Cam MGA's. Unfortunately, I gained own- ership of YD3.514 along with YD3.2403. It was scrap. I never received the engine which Lyle York has listed in his print out. In fact, all I got was some suspension pieces and the rear axle assembly. The frame was so rusty that I never went back to pick it up.

The other two Twin Cams are YD3.2403 and YM3.1371. The former is a complete car which I bought from a friend who moved here from Texas. The engine and gearbox are out of the car

denly I was going sideways. Quickly I depressed the clutch and coasted to the side of the road. I tried starting the car, there was no response.

I had the car towed home and tried tolocate the problem. The starter motor would not turn the engine over, I then tried to turn the engine over with a wrench, my worst fears were con- firmed - the engine had seized. My imagina- tion ran wild as to what broken and twisted metal must lie within. Well1 was deeply involved in my education and career so the car remained idle for rather more than 3 years.

I partially restored the car and I found that a bearing had seized on the crankshaft. As this was my first engine rebuild I was quite proud of myself. After about a month of driving, I took the car out to a bridge that is 6 lanes wide and 6 miles long for a high speed run. It was on a Sun- day with very little traffic. I managed to get the car up to a speed of 110 mph as indicated on the speedometer, I don't know what the actual speed was because of speedo error etc. I would not attempt to do this today, being a bit more cautious and traffic rules have become stiffer since we have changed to the metric system in Canada. (I think I would be in jail).

and apart, but the frame is not rusty at all and the only body rust is in the boot floor. 1 expect to someday restore the car but the original close ratio gearbox has been replaced by a standard unit. The number on that engine is 16GBU 1216 and I have no idea if that is the original one or not.

The last one is my pride and joy. It is YM3.1371. 1 bought the car from Elliot Perry in Waldorf, Maryland many years ago. It also was a very original, solid car but the engine had been replaced by a push-rod type and the body was badly beaten, probably showing a previous owners feelings about the car! I restored the car to original condition from the frameup including a replacement engine AEH37RS14706 which I located in northern New York State. I've added

YM3.1371 owned by Jeff Fishnel and part subject of the above letter.

In 1973 I put the car up for sale in Road and Track magazine. I had a number of enquiries about the car but nobody with cash in hand. I decided to keep the car and have stored the car for the last ten years. I have lived about 80 miles from my parents home where the car is stored. I put oil on any parts that will rust, and every 6t months I start the car up. The brake and clutch cylinder seals have deteriorated with the loss of action below. The car's body is basically sound with no major rust, the frame is rusted in a few places and requires work.

My main problem is finding a garage where I can restore the car, as I live in a high rise appart- ment building. I am planning to buy a house with a garage in the near future. I am currently taking a welding course at night school so I will keep this car quite a number of years to come as to sell it now, I would feel I was getting rid of an old friend. I am currently trying to locate previ- ous owners, and will send you some pictures of the car, they are stored away somewhere a t my parents home.

I have decided to take out membership with the MG Car Club, so I hope to correspond with you in the future.

an original anti-sway bar and Lucas 576 fog lamps mounted on reproduction factory brac- kets and a luggage carrier. By the way, I haven't seen original fog lamp brackets advertised in England and Clarke Spares in Doylestown, Penn. is reproducing them from a new original sample. They are first rate in quality and plating. They sell for about $65 per pair.

I would appreciate several more applications for membership for the MG Car Club for my friends. They would like to loin but never really knew how to go about it.

Other MGs I own include a 1932 J l , 1948 YA, 1953 TD, several MGA roadsters, and many parts and part cars, I've sent along a picture of my Twin Cam coupe. If I can ever be of help to you in any way please do not hesitate to write.

22 SAFETY FAST. October-November 1983 Twin Cam Group Supplement