Rare 1968 Porsche 911E Sportomatic – road test

2015 / 2016 Drive-My

At a Glance: Ten more bhp for Porsche engine due to fuel injection. With optional Sportomatic transmission, performance as sparkling as ever and car even more tract-able in traffic. Even better roadholding due to fatter tyres and longer wheelbase; self-levelling front struts keeps the balance with heavy loads. Superb seating and cockpit layout, but ventilation not perfect. Thorough Porsche engineering — a real GT car.

Almost since the first cars were sold, the Porsche following has really amounted to a religion. From early, ill-handling cars based on VW cars. Porsches have been steadily development and now they are rather special and very select machines. The superbly engendered 911 — introduced 52 years ago, banished all traces of VW ancestry, and must be judged among the world’s best GT cars.

Though technically advanced from the start with flat-six ohc air-cooled engine, all-independent suspension and four-wheel disc brakes development goes forward all the time. Improvements for 1969 include fuel-injection on the more expensive cars, self-levelling i.f.s. damper struts, a slightly longer wheelbase and better road-holding from wider wheels and tyres. Last year’s Porsche introduced a semi-automatic transmission — an option that has proved popular on the Continent, though it was originally aimed at the US market.

1968 Porsche 911E Sportomatic - road test

With so many technical options it was difficult to choose our test car, but eventually we selected a 911E with Sportomatic transmission. The 911E is really the “standard” six-cylinder car replacing last year’s (1968) 911L. Putting the 911E into perspective, its 140 bhp 1,991cc. engine compares with 110 bhp for the ‘budget’ 911T. with 170 bhp for the much quicker 911S, and with 90 bhp for the 4-cylinder, 1,582cc.-engined 912. It may seem out-of place for an enthusiast’s sports coupe to be offered with clutchless transmission, but Porsche have already proved its worth with two outright wins in the gruelling 84-hour Marathon de la Route.

Porsche five-speed gearboxes are so superb that any clutchless control has to be thought out with care. Basically, Sportomatic combines a four-speed all-synchromesh gearbox with a clutch controlled via hand pressure and switches at the base of the gear lever, plus a hairy-chested Fichtel and Sachs torque converter always working busily to multiply torque  effort and smooth out the power line. The clutch is disengaged when the gearlever is moved in any direction (except to the right when third or fourth is engaged). Moved to the left and forward, it positively locks the transmission for parking. This is by no means an automatic gearbox as all gear changing is done by the driver. Even so there is ample power and torque multiplication for the gear lever to be left in second or third in heavy traffic, letting the torque converter get on with the job of matching engine power to road speed.

Because we have no Autotest figures for the 911L, we don’t know how much more effective is the latest 140 bhp injection engine, nor to what extent Sportomatic takes the edge off performance; but by any standards the 911E is quick. A mean maximum speed of 130 mph and acceleration from rest to 100 mph in 25.9 sec confirm this. However, according to the detailed Porsche handbook, which includes performance curves for the five-speed car predicting a flat-out maximum of 133.5 mph and 100 mph in 23 sec, the torque converter must be very efficient and power losses small.

Because there are only four gear ratios, Porsche have rejigged the transmission a little. Top gear is little altered (3.69 instead of 3.79), while the lowest ratio is nominally 9.23 instead of 13,7-to-1. The torque converter has maximum multiplication of around 2-to-1, so at converter-stall the ratios are effectively lower than before. Generally and especially for maximum acceleration, Sportomatic must be usee as a manual gear box. From the standing star- first gear is selected, revs are built up to stall point (2,800 rpm on this car), then brakes released with the throttle floored. The car surges forward with revs rising only slowly at first, but once above 4.500 rpm (maximum torque) revs build up very quickly to the permitted limit of 7,000 rpm.

The electric-cum-vacuum clutch control is so quick and precise that gear-changing really is as fast as one can move the Fever clutch release occurs as soon as there is any pressure against the lever, there is no jerk or delay as long as the throttle is released in the normal way. Heel-and-toe or “double declutching” are not necessary. Idling speed in gear is about 900 rpm, with quite noticeable creep. It helps to avoid a nasty jolt if first gear is selected before the car has come to rest.

Using all the gears, getaway is quick and smooth, with 60 mph possible in 9.8 sec. compared with 8.0 sec with the 160 bhp 911S we last tested. Knowing that some buyers will use the car as an “automatic” in town, we also took figures in top gear alone. Naturally, low speed pick-up is leisurely indeed. 60 mph needing 18.1 sec and the standing start ¼ -mile 22.2sec. In other words a spirited Mini or Imp driver could  almost stay on terms with a Porsche 911E driven in top gear from the traffic lights. From them on of course, the Porsche would continue to surge forward, reaching 100 mph in around 47 sec without a gearchange; but it is a silly misuse — the gears are there to be used as — much as in any manual car.

Sportomatic, then, is a good compromise, whether in heavy traffic or on long cross-country journeys. Top gear alone is usually quite enough to keep up with flow in towns, third is splendid for rushing briskly round the lanes, and second ideal for bursting past short traffic hold ups. With maxima of 107 mph in 3rd and 80 mph in 2nd before the ignition cut-out limits further exuberance, the Porsche is illegally fast for Britain in any but its lowest gear. In open country, so good and well coordinated is the change that there is every incentive to match ratios to conditions.

Unfortunately, the performance is marred by excessive noise, both inside and outside the car. Much of it is from the powerful air-cooled engine. The new high-capacity discharge ignition system emits a continuous high-pitched whine from the region of the left rear quarter of the car. Porsche arc understandably disturbed about this, as prototype sets were quiet, and are working to make later production models silent. The engine itself is powerful (70 bhp per litre) and can produce the sort of bark which sends some drivers, in to raptures. It becomes thoroughly irritating as the noise fluctuates in sympathy with the torque converter. Even at 60 or 70 mph cruising speeds the noise is obtrusive and this, in our opinion, is now Porsche’s main problem in further refining this exclusive grand tourer. In complete contrast, wind noise is very low, indicating an efficient shape which is confirmed by the good deceleration curve.

The Porsche high-pressure fuel injection system is well behaved, with absolutely no flat spots in the power curve, but to suit the stringent US “clean-air” pollution laws the overall settings are a little weak. Starting the 911E is a real toil, with prolonged churning needed on the starter before the engine eventually picks up on a couple of cylinders. Overall settings may also have something to do with the popping and banging in the exhaust system, which worsened during the test.

The engine is happy to run on 4-star Premium petrol, returning an overall consumption of 19.0 mpg. This is not remarkable for a two-litre car, but creditable when performance and power output are considered. A point worth remembering is that the Porsche’s dry sump lubrication is fed by Shell Rotella S (SAE 30 grade) oil, normally a commercial grade and much cheaper (2/- a pint) than modern multi-grades. There is now an optional 22gal. fuel tank (13.5 gal. on our car), which allows space for only a collapsible type of spare wheel. 1969 Porsches have a wheelbase increased by 2.25in., simply by lengthened semi-trailing wishbones, with rear wheels thus moved back relative to the rest of the structure. Because the preponderance of weight was at the rear, this change has slightly improved weight distribution, though our weighbridge calculations show this to be still 40 per cent front, 60 per cent rear, as was the case with the 911S we tested. However, 6in. wide wheels with larger (185-15in.) Dunlop SP tyres, are fitted so the overall balance is even better than before.

No ordinary driver will ever have to worry about the limits of adhesion. Overall grip and balance are superb, helped again by Sportomatic which does not allow high torque reversal at the rear wheels. Normally the car can be swept along with mere brushes of the steering wheel and on sharp comers taken hard it is possible to get the inside front wheel dear of the found with the whole car still feeing stable. Handling balance is almost neutral with some built-in understeer on tight corners easily balanced by an urgent tweak on the wheel when setting up. Grip is still very good in the wet and wheelspin is just about impossible.

Driven really hard (much too hard for safe road use) the 911E will eventually break away at the rear, in predictable rear-engined manner, in a civilised and easily catchable way. Lifting off on tightening bends causes some tuck-in and momentary instability, but this never gets out of hand. The new self-levelling front dampers are not in evidence in normal driving, though they keep the front of the car at the same height regardless of load. They have also cured much of the high frequency pitching that earlier Porsches used to suffer. On the fatter tyres, ride is generally very good, and little road noise is transmitted.

The steering is light, even at parking speeds, and superbly accurate, but on uneven corners there is quite a lot of steering reaction. This is not kickback, but brings a rather disturbingly alive feel to the steering that some drivers found disconcerting.

Strong side winds on exposed roads blow the car about quite noticeably. This instability seemed to be self-damping and might be alleviated by different tyre pressures.

In previous years there has been criticism of Porsche braking balance, more noticeably in the wet, but our 911E seemed nicely set-up for normal use. Though there are disc brakes all-round, there is no servo, and retardation at low pedal pressures is slight. The pedal always feels rather dead and the brakes lack bite, needing a really firm shove for quick stops, but there was virtually no deterioration in performance in fade testing and the discs are little affected by flood water. The separate drum handbrake is not very efficient when used as an emergency brake, but held the car very easily on a 1-in-3 test slope; a re-start on this gradient was child’s play, thanks to the torque converter.

It would be a very finicky driver who could not get comfortable, as there is ample seat adjustment and back rest choice. The pedals including full size brake pedal) are nicely laid out and the new, smaller, steering wheel seems more appropriate to the precise control: the gear lever is only inches away from the wheel rim, but the pull-up handbrake is too near the gear lever, almost touching it when pulled up and reverse gear selected. For a small man, the wipers park rather obtrusively at the foot of the screen, and for none of us 4vas there a sensible left foot rest. The front seats themselves are very comfortable indeed offering plenty of support for spirited motoring, rear seats are for really occasional use being more useful when folded forward as luggage ledges.

In keeping with the sporting performance is the comprehensive instrumentation and controls. We liked such details as the clock with “time of start” hand, die oil level gauge, and the three-speed windscreen wipers with column control and generous washers. Door trims have been re-styled to in dude flush-fitting opening “handles” and more stowage space. The hazard warning switch beside the column is easily confused with the lamp switch.

Porsche make great play of the improved heating and ventilation, but this still lags behind cars with water-cooled-engines for sheer volume and adjustment control. Extractor vents along the top of the back window frame are one of the 1969 additions, but their effect is not noticeable; rear quarter windows must be opened to let stale air out of the car. Heater efficiency is dependent to some extent on engine speed, although there is a variable speed electric fan.

There is no really precise way to describe a Porsche’s total effect on discerning motorists. Three years ago, when we first tried the 912, we said “There is something about a Porsche which gets you. It takes a day at the wheel for the bug to bite, but from then on the attraction blossoms…” With Sportomatic to ease the effort even further, and fuel injection to produce a more refined engine, even an Anglophile would weaken. For those who are not addicted to Porsches, the performance and high quality of workmanship are the main attractions.

Lift the boot carpet, and the fuel tank and spare wheel are revealed. There are batteries in each front wheel arch.

Front seats on this car did not swing far enough forward, due to experimental seat belt mountings on the seat itself, the occasional rear seats are shown here folded down for use as luggage trays. The T-handle in the door jamb releases the rear engine lid 1969 Porsches have extractors built into the roof panel, but they were none too effective on this car.

Front quarter detail. Panels under the bumper knock out to make way for optional fog lamps. The big front disc brakes are clearly visible through the alloy spoked road wheel.

 DETAIL TECH DATA
ENGINE
Type Porsche 2.0-liter air-cooled 
Cylinders 6, flat horizontally opposed
Main bearings 6
Cooling system Ducted air and fan
Bore 80.0mm (3.1 ¼ in.)
Stroke 66.0mm (2.6 ½ in.)
Displacement 1991 c.c. (125.1 cu. in.)
Valve gear Single overhead camshaft, one per bank
Compression ratio 9-to-1. Min. octane rating: 99RM
Fuel injections Bosch-mechanical D-Jetronic fuel injection
Fuel pump Bosch high pressure mechanical
Oil filter Full-flow, replaceable cartridge
Max. power 140 bhp (DIN) at 6500 rpm
Max. torque 129 lb. ft. (DIN) at 4500 rpm
TRANSMISSION 
Gearbox 4-speed Fichtel & Sachs with torque converter
Gear ratios Top (Auto) 0.961
Third 1.217
Second 1.631
First 2.400
Reverse 2.52
Final drive Spiral bevel 3.85-to-1
Mph at 1,000 rpm in top gear 22.5
DIMENSIONS
Lenght 13.8ft
Width 5.35ft
Height 4.4ft
Front track 4.55ft
Rear track 4.37ft
Clearence 6in
CHASSIS AND BODY 
Construction Integral, with steel body
SUSPENSION 
Front Independent; MacPherson struts, lower wishbones, longitudinal torsion bars, telescopic dampers including self-leveling struts, anti-roll bar
Rear Independent; semi-trailing arms, transerverce torsion, telescopic dampers
STEERING 
Typo ZF rack and pinion
Wheel diameter 15 ¼ in
BRAKES 
Make and type Dunlop ATE ventilated discs front and rear, split-circuit with duplicated front-wheel systems, separate drum handbrake
Servo none
Dimensions F, 10.8 in. dia. R, 11.5 in. dia.
Swept area F, 229.5 sq. in.; R, 208 sq. in.
Total 437.5 sq.in. (350 sq.in./ton laden)
WHEELS 
Typo Forged light alloy, 5-stud fixing, 6.0in. wide rim
Tyres – make Dunlop
-type SP radial ply tubed
-size 185-70HR 15in.
EQUIPMENT 
Battery 12 volt 72 Ah.
Alternator 65 amp a.c.
Headlamps Bosch quartz-iodine 220/110 watt total
Reversing lamp Twin tandard
Electric fuses 12
Screen wipers Two-speed with intermittent-wipe
Screen washer Standard, electric
Interior heater Standard
Heated backlight Standard
Safety belts Standard
Interior trim Leather seats, pvc headlining
Floor covering Carpet overall
Jack Screw pillar typo
Jacking points 2 each side under sills
Windscreen Laminated TRIPLEX
Underbody protection Rubber compound overall
MAINTENANCE 
Fuel tank 13.7 lmp gallons (62 litres EU)
Cooling system 16 pints ( 9-litres including heater)
Engine sump 10 pints (5.7 litres). SAE 30. Change oil every 5.000 miles. Change filter every 5,000 miles
Transmission 3.2 pints. SAE ATF. Check every 10,000 miles
Final drive 2.6 pints. SAE 90EP. Check every 10.000 miles
Grease No points
Valve clearance Inlet: 0.012/0.014 in. (hot/cold) Exhaust: 0.012/0.014in. (hot/cold)
Contact breaker 0.016in. gap; 35-41 deg dwell
Ignition timing 22 deg. BTDC (stroboscopic at 1,700 rpm)
Spark plug Typo: Bosch W175 T30. Gap: 0.28in.
Compression pressure 156 psi.
Tyre pressures F, 27; R, 26 psi (normal driving) F, 29; R. 20 psi (high speed) F. 30: R, 31 psi (full load)
Max. payload 648 lb. (294kg)

TEST DRIVE RESULTS
ACCELERATION 
ACCELERATION FROM REST 0-30 mph 0-40 mph 0-50 mph 0-60 mph 0-70 mph 0-80 mph 0-90 mph 0-100 mph 0-110 mph
3.7 sec 6.4 sec 7.3 sec 9.9 sec 13.1 sec 17.2 sec 22.4 sec 28.6 sec 42.1 sec
0-40 kph 0-60 kph 0-80 kph 0-100 kph 0-120 kph
10.0
Stand 1/4 miles 17.0 sec – terminal speed 83 mph
Stand 1km 30.8 sec – terminal speed 106 mph
SPEED IN GEARS (at 5100 rpm) FIRST SECOND THIRD
0-51 0-84 22-124
ACCELERATION IN KICKDOWN 10-30 mph 20-40 mph 30-50 mph 40-60 mph 50-70 mph 60-80 mph 70-90 mph
2.1 sec 2.5 sec 3.1 sec 5.0 sec 9.1 sec 9.9 12.4
40-60 kph 60-80 kph 80-100 kph 100-120 kph
4.0 4.3
MAXIMUM SPEEDS mph kph rpm
Banked Circuit (mean) 130 209 6.470
Top Best  134 216 6.670
3rd 107 172 6.740
2nd 80 129 6.800
1st 55 89 6.880
Terminal Speeds: at 1/4 mile 83mph 17.0sec  
Terminal Speeds: at kilometre 187
Terminal Speeds: at 1/4 mile 179
FUEL CONSUMPTION
Touring (est.) 17.9 mpg / 15.9 litres/100 km – Consumption midway between 30 mph and maximum less 5 per cent for acceleration.
Overall 18.1 mpg / 13.7 litres/100 km
Fuel grade petrol 98
Tank capacity 16.5 galls / 75.5 litres
Max range 550 miles
Test distance 1713 miles
NOISE dbA Motor rating (A rating where 1 = 30 dbA and 100 = 96 dbA, and where double the number — means double the loudness.)
30 mph 58 10
50 mph 61 11
70 mph 64 11
Max revs in 2nd 69 12
SPEEDOMETER (mph)
Speedo mph True mph
30 29
40 38
50 48
60 58
70 68
80 78
90 88

 


Figures taken at 3,300 miles by our own staff at the Motor Industry Research Association proving ground at Nuneaton. All Drive-my test results are subject to world copyright and may not be reproduced in whole or part without the Editor’s written permission.

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