Porsche 911 2.7 Carrera MFI vs Carrera 3.0

by John Glynn | Oct 26, 2009 | Classic Porsche Blog, Modified Porsche Hot Rods

Early impact-bumper Carreras  – the 1974/75 Porsche 911 2.7 Carrera and 1976/77 Porsche 911 Carrera 3.0 – are some of the most misunderstood 911s ever made. John Glynn looks at two interesting examples, with not a lemon in sight. (First printed in 911 & Porsche World magazine).

Citrus Carreras

The sun finally emerges from behind wispy white clouds and treats our retinas to a cascade of colour. Non-911 people looking at these cars, and their drivers of a certain age, could be forgiven for misguided references to mid-life crises, but there is more to these pukka Porsches than a bit of loud paint.

The first impact-bumper 911s arrived in the showrooms in late 1973, ready to appeal to a whole new audience. First registered in November of that year, the Lime Green car seen here is a very early 2.7 Carrera. Both American and Rest-of-World (RoW) Carreras have the same engine capacity, but while the 49-state US versions use an emissions-conscious 165 bhp K-Jetronic version of the 911S engine, RoW 2.7 Carreras feature the 210 bhp mechanically fuel-injected 2.7 engines of the ’73 RS, and are quite a different beast.

Nigel Watkins first spotted this car hidden in an Autofarm barn. Nigel, a long-term 911 enthusiast, immediately recognised race potential in the tired 2.7, and a deal was soon agreed. The colour was then metallic black, but evidence of factory Lime Green paint abounded. Ever keen on detail, Nigel decided to return the car to its original ‘74/’75-only shade.

2.7 Carreras predate the galvanising introduced for the 1976 model year, and many have fallen victim to the ravages of rust. The urge to convert corroded Carrera bodywork to ’73 spec has been too much to resist for some owners, but despite his love of the Carrera RS, Watkins chose not to backdate. A bare-metal respray in January 2006 produced this incredibly vivid vehicle, with impact bumpers intact. Nigel’s commitment to the chunky-cornered look was not in vain, as later that year, the car won a deserving Best of Show at Classic Le Mans.

Participation in the 2006 Curborough Sprint Championship also brought rewards. Following a very competitive season, Limey eventually won the championship outright. The win earned the Carrera further specialist attention, this time at the hands of Bob Watson. Bob is well regarded amongst the 911 cognoscenti, particularly for his in-house chassis dyno and excellent results on tuning MFI-equipped cars. Wrapped up for the winter in Watson’s workshop, Limey’s engine was removed for rebuilding.

A knock from cold was traced to the intermediate gear, so a lighter (drilled) steel unit from a 993 replaced the worn aluminium original. The motor was balanced and blueprinted, with a flowed crankcase, matched combustion chamber capacities and the heads polished, ported and matched to the manifolds. Once reinstalled, the engine was run-in on the dyno and tuning began. MFI pump condition is critical to horsepower, and Limey’s pump turned out to be a cracker. With tweaked fuel rates and ignition timing, the refreshed powerplant produced an excellent 237bhp.

An engine bay refurb and a transmission service, including the addition of a ZF limited slip differential, were completed at the same time. Southbound Trimmers provided the pièce de résistance by retrimming the original sports seats in proper perforated leather, lifting Limey to almost perfect condition.

The relative rarity of the 2.7-engined IB Carrera, with less than 1,550 road cars produced over two years, has brought renewed interest to the model in the last few years, with a corresponding rise in prices. Nigel’s investment in professional restoration and period detail meant Limey was now a valuable commodity. The double-edged sword of rising prices made racing the rare bird more risk than Watkins could bear. A difficult decision was made to let Limey go, in favour of a more motorsport-focussed 964RS.

Neil Dickens was the man chosen to supply Limey’s replacement. Dickens’ dealership, The Hairpin Company, had the right RS in stock, and soon found an enthusiastic new owner for the 2.7. Neil has sold many noteworthy RSs over the years, and drove the ’74 Carrera daily while the deal was going through, so has some insight on driving the 911 that straddles the line between early and impact bumper.

“The car is entertaining in its own right, and the driving pleasure is readily accessible, but it lacks that iconic effortlessness,” declares Dickens. Serial Porsche owner Vic Cohen agrees. Cohen, who has owned two RS Tourings and currently runs a brace of Blood Orange cars; a 2.4S and a 993 GT2 CS, describes the ’74 as “flat” in comparison to the all-conquering ’73. “The car had an impossible act to follow,” notes Cohen. “Even nowadays, what can match the poise of the Carrera RS?”

It’s tempting to write off the first IB Carreras as a step backwards in performance, and there’s no doubt that the weight added to IB 911s in order to maintain their marketability created a dynamic divide between old and new. But despite the shared power source, comparing ’73 RS to ’74 Carrera is not comparing apples with apples. The modern equivalent would be like comparing a 996 GT3 RS with a 997 C2: an almost irrelevant head-to-head. A significantly lightened impact-bumper machine would make a much better yardstick. Enter the orange car.

I first encountered this 1976 Carrera 3.0 on the Pelican Parts Porsche forum in 2004. The owner was GeorgeK, a Swiss 911 aficionado who at that time also owned a very nice 930 – and a ’73 RS. George is the anorak’s anorak, combining encyclopaedic 911 knowledge with a heartfelt appreciation of the heritage, and a love of the flat-six driving experience.

George bought his Carrera 3 in 1996, from much-respected Swiss Porsche specialist Alain Pfefferlé, an RS and RSR owner and hillclimb champion in his monster 935. Then finished in Copper Brown, the Carrera was wonderfully period, with two-tone sports leather in black and cream. The car was used daily for 18 months, until medical student George inherited a BMW at a bargain price. This allowed the Carrera to be taken off the road for restoration. The aim of the rebuild was to provide a fun car for use in the Swiss Alps surrounding George’s home. The shell would be repaired where necessary, strengthened where possible and then the car would be rebuilt on a lightweight RS theme.

Space is at a premium in Switzerland, and finding a place to work on the C3 was no easy task. Claudio Ciutto came to the rescue, donating a spot in the corner of his bodyshop, where the Carrera would eventually be painted. Workspace sorted, the car was stripped, and the shell and doors were sent for acid dipping.

First job on the post-dipping list was to protect the bare metal with primer, before repairing the usual IB rust spots: one b-post, windscreen corners and inner wings by bumper mounts. The work was done on a jig, as the car had previously been down the road on its roof, and this was an ideal opportunity to correct some of the lesser-quality repairs following that accident.

Myriad modifications were made to the shell. Strengthening was added to the rear shock towers and front aperture corners, and strut tower brace brackets were fabricated, all the patterns coming from an RSR. Upgraded rear anti-roll bar mounts were fitted, and superfluous holes in the tub were welded shut, including the vents above the rear window. Before a repaint in satin black, the interior was modified with a bulkhead battery master switch, lower seat rails from a late 3.2 Carrera, and welded mounts for an aluminium Heigo roll cage. The front panel was cut and boxed and a custom oil cooler installed, fed by hand-cut slots in the front valance. The rear bumper was slotted and lightened, a fibreglass valance was fitted and the bumperette holes were welded shut, pads replaced by readily available 917 race number lights. The fuel tank was enlarged for extended range and a polished 5.5-inch Fuchs rim was modified for use as a spare.

The lightweight parts fest continued. Aluminium was used for the front undertray, torsion bar covers, oil pipe clips, fuse box, smugglers’ box and centre tunnel lids, master cylinder mount, fuel sender cover and luggage compartment heater cover. The front lid is aluminium, from a 993 Supercup racer; Ciutto expertly repairing the bonnet pin and centre filler holes. In these pictures, the car is fitted with a fibreglass rear lid from an early Turbo, but it also variously runs an early fibreglass ducktail, and an aluminium 2.2S engine cover.

When it came to picking a colour, one shade stood out: Continental Orange, available for the ‘76-‘77 model years. The shell was infused with cavity wax, and thin layers of stone chip sealant were used on the underbody and wheel arches before the paint was painstakingly applied. Ten years later, the quality of Claudio’s work remains impeccable, with only a few minor blemishes visible.

Swiss vehicle safety checks are incredibly strict, insisting on cars being presented as type approved and measuring ride heights and exhaust noise levels. The C3’s mechanical parts would therefore be left more or less factory. Suspension is fairly standard: 19 and 26mm torsion bars, with stock anti-roll bars and Koni adjustable dampers. The brakes were uprated, with 964 calipers up front, 3.2 Carrera calipers in the rear and 3.2 discs all around. The magnesium-cased transmission was overhauled, with a shorter 7:31 final drive, new synchro rings and a 40% ZF limited slip diff. The engine had hydraulic tensioners fitted but was otherwise left stock.

The interior picked up a dash retrimmed in leather and a black headliner, both wrought by George’s fair hands. A pair of silly-expensive Recaro A8 lightweight recliners was installed. A Wevo shifter with elevated billet knob went in, along with the Wevo shift coupler. The wheel used here is an ex-race Momo Prototipo. Pedal box, column stalks and so on were stripped, cleaned and rebuilt. The loom was reconstructed minus now-defunct circuits such as electric windows and centre heater controls – backdated manual heat and windows having been fitted. Uprated headlamp relays were wired in. Reap Design in Middlesex rotated the tacho face, and the clock was replaced with an RSR blank. Prototype plastic exterior door handles were fitted, with RS door panels inside. Two years after starting the restoration, ‘The Orange’ was born.

Ownership following the rebuild was challenging to say the least. In September 2002, the original engine blew. C3 engines are rare, using the 6-bolt crank of the ’73 RS and early Turbo, rather than the 9-bolt version fitted to later models, so it took almost two years to find a replacement. In late 2004, an oil line failed on a mountain drive, causing more grief. George then began working overseas, so the car remained in storage. In October 2006, with a burgeoning medical career consuming more time, and a new baby on the way, the car was advertised for sale, quickly finding a new owner. A few weeks after the mountain snow melted in early 2007, The Orange was parked in my garage.

Changes to The Orange in my ownership have been few. The 7 & 9” Fuchs gained grippy 16” Michelin Pilot Sport Cup tyres, Ferodo DS3000 brake pads were fitted all round, and the heavy 18 kg battery was replaced with a lightweight Optima unit, mounted in the smuggler’s box. Seemingly strong dyno runs, showing 202 bhp at 5400 rpm, revealed a fuel pressure problem at high revs, duly rectified. With the marvellous Michelins, bulletproof brakes and a recent fuel and ignition system sort out, this little car now drives like a demon.

Torque of 255 Nm is identical to the 2.7, but the timing of the softer cams required by the K-Jetronic injection means C3 torque peaks 900 revs lower, at 4200. Combine the low-down torque with light weight, LSD, a shorter final drive and a slick Wevo-assisted shift, and you have a car built for back roads. The Recaros offer total support, and the lower seat height, higher shift knob position and reduced gear lever throw complete the perfect driving position. Stamp on the throttle in a standard C3 at 30 mph in fourth, and you’ll hit 100 almost 8 seconds faster than a 930 of the same vintage. Imagine what a lightweight feels like.

En route to our second location, I check the 2.7 in my 935 door mirror and the mile-wide grin on Dickens’ face is unmissable. Turning on to the beautifully undulating B4100, we open the throttles, our 911s living up to their exuberant exteriors. A little later we swap cars; I slide into the smooth driver’s seat of the 2.7 and prepare to be amazed.

The Orange weighs 960 kilos on an almost-empty tank, so driving the heavier 2.7 is disappointing at first. The bulkier chassis dulls the edge typical of lightweight torsion bar cars like the ’73 RS and the stripped-out C3, but something is still amiss. It is of course my own fault – I have forgotten that with wilder cams and 7300 rpm redline, Limey hides its 237 bhp higher up the range. Double-checking the rev counter and resetting my expectations, we start again.

Now the unmistakeable gruff howl of SSI heat exchangers penetrates the comfortable cabin, and at 4500 rpm, the car takes off. As the revs tear past 5500, induction and exhaust erupt in tumult, and Porsche pedigree floods through the controls. First gear, second gear, third gear come quickly, showing 40, 70, the magic ton on the speedo. The competition suspension geometry is evident; despite a weight disadvantage, this car on Yokohama A022A rubber is eminently driveable. Limey runs an original ducktail without the chin spoiler introduced in 1975 to balance the bigger tails, but the absence of front aero does not induce a noticeable tailward bias: it feels perfectly solid whatever I try. The brakes are not as sharp as expected, given that the Carrera runs Turbo discs and calipers, but a firm shove on the middle pedal calmly wipes off speed with zero drama.

For a long time, Limey has been one of my very favourite 911s, and driving it today is a very special experience. But my heart belongs to lightweight specials and to The Orange, a car I have dreamed about owning since I bought my first orange 911 on a trip to France at the age of 10. As I leave lovely Limey behind and settle back into my own Carrera, a smile runs through me. The bright C3 is lithe and alive; pulling harder, turning quicker and braking with the bite that only fewer kilograms can give. My R-Gruppe hot rod aches to be driven, and that is just fine by me.

Sandwiched between the increasingly expensive early cars and their more populous IB siblings, the ‘74-‘77 Carreras are still a bit of an unknown quantity, yet when properly set up and driven to their strengths, they inspire like few cars before or since. Good condition examples represent some of the best value for money out there, so if you’re in the market for an interesting 911, don’t be afraid to try one – you just might like it.
Thanks to:
Nigel Watkins
Bob Watson
Neil Dickens – www.thehairpincompany.co.uk
The Courtyard, Bicester – www.thecourtyard.org.uk