Analysis of the Type 356B Porsche Super 75
Road Test Impressions of a Beautifully-made Completely-equipped 1,582 c.c. £2,348 German G.T. Car
Although I am not privileged, like the Production Manager and Continental Correspondent of MOTOR SPORT, to have had regular experience of Porsche motoring, I was able recently to drive a Super 75 for over 1,000 miles on English roads, mostly fast miles, for this is a car that is not habitually driven slowly.
In many ways a Porsche is the modern equivalent of the pre 1939 Bugatti – expensive, but rewarding, a car for discerning owners, beautifully and individually made, and, like the famous French marque of pre-war times, somewhat temperamental, if experience of this test car, and the P.M.’s 1960 Super 75, is any criterion.
In coupé form the modern Porsche has not changed materially from the original conception of Dr. Ferdinand Porsche, dating back to 1949. Of the three body styles, coupé, hard-top and openable cabriolet, we are here concerned with the first-named, a low-drag, individually-styled car, with the Super 75 version of the rear-mounted flat-four air-cooled, push-rod inclined-o.h.v. engine that develops 75 b.h.p. (88 S.A.E.h.p.) at 5,000 r.p.m. on a compression ratio of 8.5 to 1.
The Porsche has undergone minor but significant changes down the years, for like VW, the little factory at Zuffenhausen – Stuttgart, controlled now by Ferry Porsche, believes in continual improvement of the basic car rather than model-changes at defined intervals of time. Compared to the quite early models you find a greater area of screen and rear window, less convenient adjustment of the seat squabs, more room in the engine compartment, enabling twin Zenith double-choke NDIX carburetters to be used, conventional sound-damping insulation in place of upholstery in this engine-boot, new bumpers, rather ugly wheel knave-plates, funnels over the floor ventilators to keep hot and cold air from blowing about the ankles, a new steering wheel with a horn-ring that impedes a clear view of the tachometer dial, door “keeps”, a level luggage platform behind the front seats, exhaust pipes terminating within the rear bumper over-riders which discolours them and makes it more difficult to remove the engine, and many other small items that a knowledgeable Porsche enthusiast will note, either favourably or the reverse depending on his personal likes and dislikes.
Even comparing the 1962 test-car with the P.M.’s 1960 Super 75 a number of changes were apparent—larger screen, bigger rear window, twin grills on the engine boot, a different system of fresh-air ventings, variable-speed screenwipers, different steering wheel, a heaviness in almost all the controls, and so on. Whereas this 75 b.h.p. car has the type name “1600 Super” on the engine boot lid, the test car merely had an “S” after its make name.
I am no Porsche connoisseur, although this way of motoring appeals to me, and so I deal hereafter with the current Super 75. Incidentally, there has been a further “mod.” since the testcar was made, the fuel filler on l.h.d. cars now being in a front wing instead of beneath the front bonnet, which, I understand, enables the tank to impinge to a smaller degree on luggage space and obviates petrol fumes being drawn from the filler cap and into the car via the fresh air ducts.
The Super 75 in Detail
It is general knowledge to MOTOR SPORT readers that a Porsche is splendidly constructed and finished. It is a very low car, so that you enter over a frame-sill, through doors which shut in a pleasingly positive manner of their own. The separate front seats have hard but comfortable cushions and the squabs have a big range of adjustment controlled by side levers against strong spring action, and they fall almost completely down to form rather lumpy beds. These seats are not nearly so convenient as those fitted to early Porsches, however, wherein the squab angle could be regained without operating the side levers. The doors have lockable quarter lights with the notable refinement of tiny knurled knobs that prevent the pip being depressed and thus serve to foil a thief who is not sufficiently enterprising to remove the back window. The windows lower completely with 4 1/3-turns of the handles. Normal interior handles are used, which when lifted up lock the doors, even against the key, from within. The exterior push-buttons each have locks. The aforesaid interior handles are so contrived that it is impossible to be locked out of the car if the key is left within. The rear side windows open slightly, as ventilation panels, on well-made toggles and have a knob that locks them in position. Range of vision from the driving seat is quite good in spite of the low seating position, both front wings being in view, although the scuttle is now higher than before. There is stiff crash-padding above the facia in leatherette to match the interior trim, and soft vizors.
The instruments and minor controls reflect the quality of the car but could be better arranged. Before the driver are the matching Vdo tachometer and speedometer, the former reading to “60” (6,000 r.p.m.) and being calibrated in figures by thousands, and the latter going to 120 m.p.h. The tachometer is to the right of the speedometer where its more vital readings tend to be obscured by the horn-ring. The dial is stalked from 3,000 to 5,000 r.p.m. as a reminder that nothing much happens in a Porsche until these crankshaft speeds are attained, and there is a red section from 5,000 to 5,500 r.p.m. to indicate that the engine should not be held for too long above its peak speed. The speedometer dial has straking between 30 and 40 m.p.h. to draw attention to speed limits and incorporates total and trip-with-decimal mileage recorders. It is calibrated in figures every 20 m.p.h. A faintly irritating aspect of the trip recorder is that the last digit moves up with the decimal numerals, so that a driver obeying instructions of a rally navigator might sometimes be unable to read the mileage accurately. Far more serious, remembering the high price of the car and the class of person likely to drive it, is an error of optimism as high as 6% in the speedometer readings. The tachometer commences with “6,” for 600 r.p.m., the engine of the test-car idling at 1,200 r.p.m.
The usual warning lights are incorporated in the dials of the tachometer and a right-hand matching dial, and include a warning that the side lamps are alight (green), the other lights covering dynamo-charge, high-beam (blue), oil pressure (green) and direction-flashers. The right-hand dial indicates oil temperature at the top and fuel contents at the bottom. Unfortunately, although the needle-sweep is considerable, there is no longer any calibration of this thermometer, an indication that even at the Porsche factory the salesmen are taking over from the engineers! The fuel gauge is marked “0,” “2/4,” “4/4.”
Unlabelled neat black knobs are spaced rather haphazardly about the metal facia. That to the left of the steering wheel looks after the wipers, its knob turning to vary the blade speed from 40 to 80 strokes per minute. Next to it is the cigar lighter; it would be better were these two knobs reversed, because should the driver want to put the wipers on or off at the same moment as the passenger feels in need of nicotine, their hands must cross. Set up rather awkwardly behind the wheel is the lamps-control knob, bringing in first side lights, then headlights, and the rheostat instrument lighting by rotating it. A hand-throttle knob is set to the right of the lamps-knob, also behind the wheel; it pulls out against serrations to increase engine speed and turning the knob locks it in position.
A foot-operated screen washer, that squirts over the roof on too-vigorous pressure, is supplied from a plastic reservoir holding about 1 1/2qts. of water. Out of sight below the facia, but easily reached, is the useful reserve fuel tap, labelled ” RES,” ” ZU,” ” AUF,” that brings in rather more than a gallon of fuel. The petrol filter is located at the base of its operating-rod, but is out of the way of the driver’s feet. A draw-type ash-tray is provided, also provision for a facia-mounted radio, above which is an accurate Vdo clock.
To the right of the 3-spoke steering wheel is a neat little stalk that controls the direction flashers, flashes the lamps if pulled up, and dips the headlamps of pushed down. Lamps flashing is on dipped beam if the sidelamps are alight, full beam in daylight, or, of course, from low-beam to high-beam. Some drivers will prefer a separate lamps’ stalk, as it is possible to signal a turn inadvertently when operating the lamps in a hurry. A small-diameter horn-ring on the wheel sounds a loud horn but was rather stiff to use. The steering wheel is set sensibly low, although somewhat higher than on earlier models, to offer breathing space to German stomachs.
The heater controls are very neat – just a small quadrant with selection of off, ventilation to screen and ventilation to car, with a knob in front of the gear lever to bring in warm air. This knob calls for many turns and on the test car hot instead of cold air was directed on the feet even when it was screwed down. Markings on the quadrant are by International colour code. The chassis rails incorporate the air outlets with those neat sliding vent-hoods, now with funnels to direct the air forward. Another quadrant provides for a gasolene heater, if fitted.
On the extreme right of the metal facia is the ignition-key-cum-starter. Internal stowage in the Porsche is generous. Both doors and scuttle possess big pockets. There is a lined lockable cubby-hole, although it is too small to take a Rolleiflex camera. Its lid has elastic bands for holding pencil, route-card, etc. Twin non-swivelling anti-dazzle vizors are fitted, with a mirror for the lady passenger, and the rear-view mirror is of very effective anti-dazzle type. There is a neat VW-type Hella interior lamp on each side, each having its own switch which can be set for courtesy action. These lamps are usefully bright. Coat hooks are provided, also metal door “pulls” and a metal grabhandle on the facia. The fuel tank and spare wheel occupy much of the space in the front boot, the lid of which has been enlarged recently, but there is useful stowage for soft bags, etc. A nice point of detail, typical of Porsche development, is that the bonnet-lifting handle is now rigid, to prevent it buckling when a heavy-handed pump attendant leans on it while closing the lid. Most of the luggage, of course, goes behind the main seats, two occasional seats, very nicely shaped and leather-upholstered, having backs that fold forward to make a flat, cloth-faced platform. On this sizeable suit-cases can be carried; lugs are provided for luggage straps but the straps themselves have to be bought by the owner. The front boot knob remains on the near-side in r.h.d. cars, which is rather casual in a car costing £2,400. The same applies to the engine-lid release knob. There is a rather “fumbly” safetycatch for the front boot lid and an emergency nylon rope for opening it should the main cable break—but this reduces the thief-proof effect. Both lids are self-propping; some people consider they should be separately lockable, to obviate locking the car doors.
The fuel tank has a commendable size filler orifice. A gear lever lock is provided at the base of the lever. Incidentally, a very clear and comprehensive driver’s manual, on VW lines, is issued with the car. The test car was impeccably turned out, with spares kit, workshop manuals in English, a tin of oil, etc., but, as will be seen later, I would have been happier had the engine been developing its full power.
On the Road
The Porsche is essentially a low and small car and a driver unfamiliar with it has to get used to this and allow for the sensation that it is pivotting on the inside back wheel round acute corners. The driving position is very comfortable, although pedals offset to the left (the brake pedal is in line with the steering column) and the generous length of seat cushion may combine to cause leg strain.
This is essentially a car you “wear ” rather than merely sit in – getting over a sill into the driving seat. Although so compact, only a very long-armed driver would be able to reach over to open or close the near-side rear vent-window from his seat, yet he has ample leg, elbow and head room in this compact G.T. coupé.
The rigid central gear lever is delightfully placed, its movements conventional, with reverse easy to find beyond bottom gear position. The pull-out handbrake is moderately accessible under the scuttle but stiff to release. The treadle accelerator enables “heel and toe” gear changing.
With memories of finding the VWs lightness of control handed on to the Porsches I drove some years ago, I was disappointed in the heaviness of the 1962 version. The steering calls for some effort and becomes heavier towards full-lock, all three pedals call for firm pressure, and although the gear-lever has much shorter movements than formerly, gone is the delightfully light “non-mechanical” swopping of ratios of the earlier Porsches.
The gear change is very quick, however, the change from 3rd to 2nd particularly rapid, and there is unbeatable synchro-mesh, gear changing calling for only a flick of the clutch pedal. But it is a heavier change than I had anticipated. As it is essential to keep engine speed above 3,000 r.p.m. if any sort of performance is to be obtained, the gear lever has to be operated continually. In this respect the Porsche again recalls the pre-war Bugatti; you may remember how astonished was the wife of motoring journalist, the late Edgar Duffield, when she was driven from Aldgate to “The Bear” at Esher in top gear in a Type 44 Bugatti, because her husband’s 8-valve and 16-valve Brescia Bugattis never got out of 2nd and 3rd speed until they were well out of London. With its 3.61 to 1 top gear the modern Porsche resembles the Brescia Bugatti; of vintage days. . .
If the excellent gearbox is properly employed, extremely useful acceleration all along the speed-range is available, together with maxima of 28, 51 and 78 m.p.h. in the three lower ratios without exceeding 5,500 r.p.m., to which the engine goes without any indication of distress. Top speed is 109 m.p.h., again at 5,500 r.p.m. but 95 m.p.h. was about the best I could get on English roads. This must be qualified by stating that carburation appeared to be suspect on the test-car, which was seriously down on power compared to the P.M.s 1960 Super 75, the engine “hanging” badly at 4,000 r.p.m. For this reason there was no point in taking acceleration figures. The engine is sensitive to different fuels – it refused to look at Shell, went better on Esso Golden and better still on BP Super Plus.
But it never went properly for very long and on account of this erratic running I had a rather trying run down from Oulton Park to Hampshire, although, a Porsche being a Porsche, the average speed was still impressive. This is largely due to the great ability to pick up speed very quickly indeed from 30 to 50 m.p.h., together with a very high degree of controllability. The steering, geared just under 2 1/2 turns lock-to-lock, exhibits no free-play and is essentially accurate, and the Super 75 corners with no roll, its short wheelbase enabling it to “tuck-in” in traffic most effectively. It must look safe, too, because fellow users of the highway at far lower speeds never hoot or shake firsts at it. It is, indeed, a very safe car, possessing cornering powers and acceleration that keep it out of trouble.
The steering tendency is initial understeer, even on the test car, which lacked the extra stabiliser leaf spring for the torsion bar swing-axle i.r.s. This persists round fast bends but changes to oversteer on sharper corners. The Dunlop SP tyres (which cost extra) cling on very impressively indeed, especially in the wet, at the expense of a harsher ride than normal and rather sudden breakaway when the limit of adhesion is reached. Some die-hard Porsche enthusiasts prefer the old handling characteristics of considerable but consistent oversteer.
The ride is inclined to be lively, in a corner to corner choppiness that is typically Porsche, but only on very rough surfaces does this affect road-holding and even then steering precision is scarcely jeopardised. On unmade roads the Koni-damped suspension functions well. The steering has strong but slow self-centring action which, with the SP tyres, made it tiring on long runs. A rocking action, rather than kick-back, is set up by surface changes through the torsion-bar trailing-link and hydraulically damped, worm-and-peg mechanism. Tyre squeal is virtually impossible to produce.
The brakes call for firm, even considerable pressure, no doubt due to hard linings, and they are then fully effective for all save really savage stops from near-maximum speed, when disc brakes might be just that much more reassuring. There was considerable squeal from the anti-fade linings as the car came to rest but the brakes did not pull off-course and had no vices.
The main point of Porsche motoring is effortless fast travel in luxury surroundings. Although the characteristic exhaust note of the flat-four engine intrudes considerably under acceleration, throttled back it becomes a pleasantly quiet power unit, functioning well within its limits. Cruising at 80 m.p.h., it is turning over at less than 4,000 r.p.m., the oil thermometer well over to the safe side of its scale.
With the windows open buffeting occurs but normally a Porsche owner contrives sufficient ventilation by adjusting quarter-lights and rear vents. Unfortunately with o/s quarterlight shut an irritating air whistle intruded; there is also some transmission hum on the over-run, although the gears are silent.
Petrol consumption of 100-octane fuel varied for 30 m.p.g. driving very gently (we were tailing a recently-collected Siddeley Special at the time) to 25 1/2, m.p.g. crossing London. A fast drive to Oulton Park and back showed 27.5 m.p.g. The reserve supply suffices for a useful 38-39 miles and the total range is some 300 miles. In a mileage of 5,220 a pint of Valvoline oil sufficed to restore the sump level. The dip-stick is extremely accessible, and changing plugs with the good-quality tools provided, in an attempt (unsuccessful) to cure the hesitant acceleration, did not occupy too much time.
The engine starts instantly without choke and does not “pink” or run-on. At night the Bosch headlamps provide excellent illumination. The brake lights and flashers are incorporated in single units, incidentally, and the reflectors have been stuck on as an afterthought.
To sum up, my impressions of the Porsche Super 75 are that it is a genuine G.T. car in miniature, with accommodation for four people in fair comfort, two in extreme comfort and luxury. The care with which this highly individual car is constructed is reflected in the fine-paint finish of the beautifully-shaped Reutter body, and in the high grade leatherette and corduroy upholstery and the complete equipment provided, as well as by such effective items of detail as grease nipples on the door-hinges and thermostatically controlled hot air supply to the carburetter intakes.
Granted that the car is expensive – as tested it is priced at a total of nearly £2,367 – and that to a large extent Porsche ownership is an acquired taste, the Super 75 provides high performance from a small engine allied to the comfort and luxury expected of far larger cars and, above all, it is one of the most individualistic cars – possessed of real “character” – that it is possible to buy. I drove it for ten days only but another factor that contributes to enthusiasm for this Porsche is its durability over big mileages, about which I have asked the P.M. to enlarge in the following paragraphs. – W. B.
A Porsche Super 75 over 30,000 miles
My own Porsche Super is very similar to the car tested and a fairly accurate log has been kept of mileage, fuel and troubles.
With 104 miles on the clock, the car was collected, and run-in at the recommended speed. At the 500-mile service the speedometer was changed as the original one was 10 m.p.h. out at 50 m.p.h. The new speedometer started at 13 miles and when it was showing 1,000 miles-plus, and the car was loosening up, the pronounced understeer became annoying, so the Michelin “X” pressures were put up until a reasonably neutral effect had been reached, e.g. 25 lb. front and 27 back.
During the 1500-mile service several minor troubles were sorted out but the complained-of poor brakes were still as bad as ever, as I was to find out 3,000 miles later when in a damp lane they snatched, locking the front wheels however light the pedal pressure was, and the side of the car was “graunched” on another car.
At 6,600 miles, during service, a vibration of the gear lever was rectified, but the brakes were still terrible. I suggested different linings as there seemed no cure for the snatching, but it was two and a half thousand miles of “dodgy” motoring before Ferodo A.M.4s were fitted. This sorted out the snatching on wet roads, but appreciable fade developed when slowing from the region of 80 and 90 m.p.h. A short time later, a trip to Stuttgart was organised and arrangements were made for the car to be checked at Zuffenhausen and the brakes to be sorted out.
On the run from Ostend to Stuttgart I checked the fuel consumption very carefully and found it to be 32.2 m.p.g. with an overall average of over 70 m.p.h. Before leaving the car I checked the 0-60 time, so as to have a guide at any re-tune. This came out at 14 sec. before tuning and on the way home it took 12.4 sec. to reach 60 m.p.h. The brakes were changed back to German linings and for the first time worked very well, making the run home a real pleasure. This service at the works took place at 11,700 miles. At 13,500 miles the speedometer cable broke, and at 14,300 miles the car went in for a new cable. Unfortunately the British Concessionares detected a knock in the engine and on stripping down, they found excessive cylinder and piston wear, which necessitated a re-build. During the short period during which the engine was overhauled I was loaned a hack engine which propelled the car for 2,500 miles.
I ran the engine in again carefully, with a 1,500-mile service in Stuttgart, and the car was as good as ever. At this service the brakes were good and working perfectly, and 0.K’d. by the factory, but 5,500 normal miles later the shoes and drums were changed in England, badly cracked, since when they have snatched and pulled badly.
During last winter the screen cracked and the wipers were strained by snow, but these were repaired and as the carburation was now very “ragged” the car was tuned by the Porsche agents in Liége, with highly satisfactory results.
In the 30,500 miles to date, 1110 gallons of petrol have been consumed, giving an overall consumption of 27.5 m.p.g. Oil consumption is about 750 miles per pint, and although the car has been driven moderately fast, the Michelin “X” tyres are still the originals.
When a Porsche is going well, there is no more pleasant and comfortable car for getting quickly between two points. – M. J. T.