By on August 7, 2010

Oops! Under the influence of “Ketel One Citroen” I misnumbered this. Fixed now – jb

During the Seventies, Porsche was, as Katt Williams might say, in turmoil. Some very strong-willed men were fighting to determine the direction of what was then a very small firm. Ernst Fuhrmann, famous within the company for developing the quad-cam “Carrera” engine that made the 550 Spyder such a giant-killer, was running the show, and he wanted the 911 dead. His arguments were all quite valid: the 911 was not aging well, it was not selling well, and nobody had any idea whatsoever how to make a decade-old car conform to a raft of upcoming safety and emissions regulations.

Some of Porsche’s more paranoid fans believe that Fuhrmann all but sabotaged the 1974 Porsche 911 and its 2.7L engine. The likely truth is far more pathetic. At the time, Porsche’s engineering staff was very small, and they had three major jobs in front of them: developing the all-new 928, seeing the 924 through its teething issues, and uprating the performance of the 911 to meet market needs. Surely the last of these three jobs simply received inadequate attention.

No matter what the reason, when the surprisingly handsome 1974 911 debuted, complete with the mandatory impact bumpers for the US market, it was a complete and utter disaster. Not for the first time, and not for the last, Porsche had built a car that would grenade its engine within 50,000 miles.

This was meant to be a stopgap car, a last hurrah until the 928 could arrive and redefine Porsche as a product and a company. The basic platform was already twelve years old and had undergone just one major revision — a lengthening of the wheelbase and mild suspension re-spec designed to keep the cars from killing their owners in the rain. The original 2.0L six had been expanded to 2.4L in a failed attempt to keep up with cars like the outrageously rapid Jaguar E-Type and fuel-injected Corvette Stingray. Then, as now, Porsche always sold about the slowest sports car any given amount of money could buy, at least when straight-line speed was the measurement.

The 2.4 wasn’t really fast enough, but the impending American emissions standards threatened to slow the 911 down to the point that ordinary Cadillacs would smoke its droopy tail. The solution: to take the 2.7-liter engine developed for the Carrera RS, detune it a bit, and make it standard across the board. As it debuted in 1974, the engine had issues. The magnesium cases warped, the head studs pulled out, and all of this often happened within a few years of purchase. The valve guides didn’t last 50,000 miles, which was a problem that, in some form or another, would dog Porsche until the very last 993 left the factory.

In 1975, Porsche added a “thermal reactor” to meet US emissions standards. At the time, these were only added to US-bound cars; Porsche did not adapt its forward-thinking “world emissions strategy” until much later. The thermal reactor was a horrible, horrible approach to meeting the standards. I don’t know exactly how it works, but to be fair, neither did anybody at Porsche.

When applied to BMWs, the thermal reactor dropped mileage to the teens and cut power to the bone. When added to a Porsche, it did all of the above… but because it was cramped in the back of an air-cooled car, it also accelerated all of the 2.7L’s problems. Hello there, first-year engine failure! Don’t forget that the Porsche warranty of the day was basically one years on defective parts — and neither the dealers nor Porsche were eager to buy new engines for customers. A lot of people ended up with very expensive paperweights. At the time, a new 911 cost about four times as much as an Oldsmobile sedan.

Something had to be done, and that “something” was a move to aluminum engine cases as used in the 930 Turbo. This allowed a bump to 3.0L displacement. The resulting car was the 911 Super Carrera, or “911SC”, which debuted in 1978. That car had a whole different set of mechanical issues, one of which — defective chain tensioners — could also cause a complete engine failure, but it was far more reliable than the guaranteed-to-melt 2.7L.

If you see a 911 2.7 on the road today, chances are it’s been all squared away, either through a variety of innovative fixes or the simple installation of a 3.0. Many of these cars now provide very useful service to their owners. At the time, however, they turned a lot of people away from Porsche permanently. Porsche Cars North America’s arrogant attitude, something that continues to the present day, didn’t help matters.

I wish I could come up with a legitimate reason for Porsche’s decision to leave the 2.7L in production for three full years after they first saw problems, but if anything that represents fast service by Porsche standards. The water-cooled grenade stayed in service for eleven years, you know.

Not that anybody in Stuttgart was all that concerned about the 911’s downward spiral. It was an old car and anybody stupid enough not to wait for the far-superior 928 got what they deserved. Fuhrmann expected that 911 production would terminate some time in the early Eighties, possibly as early as 1980.

Nobody could predict that the 928 would turn out to be an expensive, troublesome boondoggle and that the air-cooled 911, far from being killed around its eighteenth birthday, would in fact go on to live a full thirty-six years in production. In that second lifetime, 911 owners would learn about a whole new range of maladies, and they would also learn that some things never change. Porsche didn’t really care then about long-term customer satisfaction, and they don’t really care now. Still, if you can get behind the wheel of a ’75 911S and hear that magic “whoooooooOOOOOOOOP” as the mill catapults you squarely out of your late apex, perhaps you won’t care about that, either.

Get the latest TTAC e-Newsletter!

44 Comments on “Porsche’s Deadly Sin #4: Porsche 911S 2.7...”

  • avatar

    This series is a real eye-opener. I live in an area with a lot of rich douchebags, and I’ve always been surprised how few (hardly any) drive Porsches. Now I know why.

  • avatar

    Amazing the jump from 3rd to 5th sin without anything between.

  • avatar

    As an added benefit once ignited, they can not be extinguished, so even if they are well sorted by now they are still one grenade away from making the nightly news.

  • avatar

    I searched frantically for the 4th sin. Was it so egregious that it cannot even be mentioned?

    And to be fair, I am sure Porsche was not alone in grenading expensive sports cars. Lambos from what I understand have been self-igniting from the days of the Miura.

    I don’t think there were any redeemable sports cars from the late 70s… except, ironically, maybe the 914?

    • 0 avatar

      Possibly the RX-7 and the 280Z/ZX? I wouldn’t give on the Celica Supra, but at least it wouldn’t self-immolate or die trying.

    • 0 avatar

      In the 1970s, automotive engineers were faced with increasingly stringent pollution standards, plus fuel economy pressures brought on the wake of the Yom Kippur war in 1973.

      We sometimes forget how much knowledge has been gained in the past 35 years regarding combustion, induction, ignition and controlling them. With 1970s technology, the task was simply too hard to accomplish, and cars sucked. They didn’t run well. They ran after you shut them off. They got crappy mileage and they were not even weak.

      Look at the V8-6-4 Cadillac engine. Nowadays cylinder deactivation is commonplace and works pretty much seamlessly. With 1980 vintage electronics and control devices, not so well.

      You can argue that much of what we know today about engine control is the result of needing to comply with government regulation. The 638HP LS9 in the ZR1 Vette owes a small debt of gratitude to the Clean Air Act. However, we didn’t regulate Neil Armstrong and Buzz Aldrin to the moon. The government set an engineering goal and provided money to do it, mostly by the private sector bidding to be contractors to NASA.

      Maybe a carrot would have been a more efficient motivator than a stick.

    • 0 avatar

      The Lotus Esprit was introduced in the 1970s. While the 907 engine has its detractors, I believe that its major shortcomings were a lack of torque at low rpm, and oil leaks. They don’t have a reputation as hand grenades. I don’t even think the later turbo versions are that prone to blowing up.

    • 0 avatar


      Possibly the RX-7 and the 280Z/ZX?”

      I’m with you on the Z (240z/260z/280z) – especially as a former owner of a 1977 280z). The early Z series had the right stuff – sleek styling, the smooth and bulletproof in-line 6, and the 4-wheel independent suspension (which I had first-hand experience installing new struts on the car)…

      But the ZX??? That thing was a serious pig-asaurus – a luxo-barge masquerading as a “sports car”…

    • 0 avatar

      I “get” that 1970s technology wasn’t always up to meeting the new regulations, but some of the emissions stuff on engines was just plain stupid.

      Case-in-point: “heated automatic choke.” Here we have the automatic choke (choke controlled by a spring that grows and shrinks as it heats up and cools off). So far so good, but to make the choke pull off a little sooner somebody invented a supplemental electric heater and controlled it with a little timer relay. Huh? The real result- a brand new car pollutes a little bit, but after a few years in cold climates this the choke is almost impossible to keep in adjustment, the electric heater pulls it off too soon while it’s warming up, and the stalls at every stop sign and red light for about the first five minutes of driving.

      Another doosie- air pumps to lower the apparent CO concentration in the exhaust and “pass” the emissions sniffer test. Dilution is not the solution to pollution! Supposedly air pumps would even out things for the catalytic converter if the engine was set to run slightly rich (worse mileage, more “driveability,” and maybe lower NOx emissions).

      Delayed vacuum advance or part-throttle vacuum retard- what exactly was the point of either of these and who were we trying to fool?

      Other things were just a sign of the times- reduced spark advance and lower compression heads to bring NOx down from unreasonable levels, throttle dashpots and/or anti-backfire relief valves to reduce trailing throttle misfire or backfire (since fuel cutoff technology was still over a decade away).

      Of course the Swedes and Germans made fuel injection, oxygen sensor feedback, and three way catalytic converters work by 1977 and about ten years later 99% of the U.S. market finally had the same thing.

      Any other big ones I missed?

    • 0 avatar

      psarhjinian Possibly…the 280Z/ZX…?

      We had a ’76 280Z. It drove like a truck (not sure it even had power steering, or if it did it wasn’t very responsive), had marginal acceleration and cornering, the interior disintegrated (seats and foam dash) after a few years in the FLA heat, and it would occasionally leave you stranded due to electrical problems. On the plus side it looked great in British racing green.

      My wife then bought a red-purple 280ZX (don’t exactly remember the year)that “sported” (it was the only thing that was sporting about it) a red velvet-plush interior that would not have been out of place in a Lincoln Town Car. And don’t forget the 80 MPH speedo. Not that you’d want to take it much faster.

    • 0 avatar

      Desireable sports cars from the late 70s? I can think of a few examples:
      – Porsche 928
      – BMW M1
      – Ferrari 308 (with carbs, not the early fuel injection models)

      Generally, the US buyers were at a disadvantage at that time due to its advanced (and necessary) emission standards with the manufacturers not yet able to meet them without hampering performance and fuel economy.

  • avatar

    When I was a kid, a guy in the neighborhood had a Porsche just like the one pictured at the top — wearing the same shit-brown paint. Despite looking like it was covered with shit, I remember how it appeared to be ultra-modern compared to the average American car of the time.

  • avatar

    How did a niche company like Porsche survive with so many horrible engines and such terrible customer service?

    • 0 avatar

      It just may have something to do with the driving experience: if you’ve never driven one, it won’t make a lot of sense to you, though. But the reliability of other sports cars (Ferrari, Lamborghini, Aston Martin, Lotus, Aston Martin et al) was rarely much better back then, and often worse.

      And, no, I won’t include the Z or the RX-7 in the “sports car” category.

  • avatar

    In 2008 I came very close to buying an early Boxter. A friend had an extremely reliable, high-mileage, 86 Carrera back in the early 90’s so I always thought of Porches as a reliable sports car. Fortunately the internets had already started whispering about the various IMS/RMS potential problems. Despite encouragement from some quarters I was spooked.

  • avatar

    And to make matters even worse, 1970’s 911 paint jobs came in shit brown, lime green and snot yellow. They not only ran like crap, but they looked the part as well.


    • 0 avatar

      I believe you’re thinking of the triumvirate of 1970’s appliance colors — refrigerators, ovens, dishwashers and the like — were all painted one of these colors. The official names of those colors were:

      1) Chocolate Brown aka Shit Brown
      2) Buttercup Yellow aka Piss Yellow
      3) Avocado Green aka Puke Green

  • avatar

    The irony is that, yes, as compared to today’s vehicles these were troublesome, but compared to the high buck sportscars of its era, it was almost bulletproof. Hell, compared to the average Vega or Pinto they were gold!

  • avatar

    Paranoia. If this is how we approached every car ever made, there’d simply be no such thing as a “good” and/or “reliable” car.

  • avatar

    The 1970’s Alfa Romeos were far from trouble free but the engines and transmissions were very solid. They solved the emissions problem in 1969 with a good mechanical fuel injection from Spica. That diesel derived system met regulations from 69 to 79 when it was replaced in 1980 with Bosch electronic. The thermostatic acuator was the only trouble spot and those were often replaced with an aftermarket manual fix. Even today, a well tuned Spica will out perform webers. The only engine issue was head gaskets (common) and oil control rings, less common.

  • avatar

    So, is there any Porsche relativey reliable for the ordinary guy?
    So far, the list of deadly sins gets longer by the day and my hopes of owning one someday is evaporating!

    • 0 avatar

      The modern Boxsters/Caymans and 911’s are fairly reliable. If it’s the IMS horror stories that scare you, find a 2009 model or newer. And while Porsche unfortunately never did completely eradicate the IMS issue from the M96/M97 engines, the problem seems to be a lot less pervasive in 2006+ models.

  • avatar

    What an awful company and line of products. I didn’t know much about Porsche’s history before this series of articles, and now I’m a hell of a lot less depressed about not being able afford them. Hello BMW!

    • 0 avatar

      @ panzerjaeger: “…an awful company and line of products. I didn’t know much about Porsche’s history before this series of articles…”

      you still don’t. this series is far from objective. it is merely ‘content,’ generated to feed the beast that is otherwise known far and wide as ‘the media’ [and permit it’s author to make a buck].

    • 0 avatar

      “you still don’t. this series is far from objective. it is merely ‘content,’ generated to feed the beast that is otherwise known far and wide as ‘the media’ [and permit it’s author to make a buck].”

      Well said. I can’t believe someone just based their whole Porsche history knowledge base on this series. I guess it’s working…

    • 0 avatar
      Jack Baruth


      Accuracy is important to me, so if I’ve made factual errors, please let me know.

      This is a series about the “dark side” of Porsche, so naturally that is what we’re focusing on. There are plenty of great things about the company and their cars.

    • 0 avatar

      Yes, because BMWs are paragons of reliability ;-)

  • avatar
    Larry P2

    “How did a niche company like Porsche survive with so many horrible engines and such terrible customer service?”

    American self-loathing.

  • avatar
    Larry P2

    “the thermal reactor dropped mileage to the teens and cut power to the bone. When added to a Porsche, it did all of the above… but because it was cramped in the back of an air-cooled car, it also accelerated all of the 2.7L’s problems. Hello there, first-year engine failure!”

    But of course, the the interior must have been gorgeous enough for most TTAC contributors and euro-cultists to cause spontaneous ejaculation.

  • avatar

    How about that gem of American engineering, the Chrystler lean burn engine? Looked like a bowl of pasta under the hood. The 70’s were the absolute worst time in American automotive development. My luck being what it is, 1975 was the first year I could afford a new Ford F150 Pickup. I replaced almost every part on that POS, and it is the reason I vowed to never buy American again (I relented and bought a 1989 Dodge Ramcharger, which I loved until the clearcoat actually chalked off the vehicle). Even though I now believe American manufacturers have now almost caught up to the Japanese and European munufacturers, the way I was treated by Ford and Dodge during these problems ensured that I would never be suckered by them again. Have I had problems with the European and Asian I have purchased since? Absolutely! but the companies always gave the illusion that they actually cared, and backed it up with service after the sale.

  • avatar

    “How did a niche company like Porsche survive with so many horrible engines and such terrible customer service?”

    “American self-loathing.”

    Status whores will always pay thru the nose to feel like they are part of an exclusive club.

  • avatar

    That brown 911 brings back memories. I had a brown 912 (the one with the 4 cyl engine in it.) It was a reliable car even though the Sportomatic transmission was an odd little beast.

    • 0 avatar

      Kind of odd a 912 couple with Sportomatic.
      Is a semi auto 3 spd , doe sit auto shift gear or u need to change yourself?
      I hear there is a micro switch when u touch or leave your hand on the shifter the elec clutch witth dis engage, means no power coming thru and u can shift to next high or low gear.
      A fnd had a VW like that but never drove her to experience it.
      porsche needed that for folks who couldn’t do clutch.

    • 0 avatar

      While it sounds a little like the 2-speed Bug semi-auto transmission it was a very different unit. I don’t think many 912s with Sportomatic made it to the US.

      It had a manual shift lever like a normal manual transmission car, except it only had 4 gears. Yes, there was a microswitch in the lever that caused the clutch to disengage and then you selected the next gear. It also had a torque converter so you could sit in gear at traffic lights.

      The most difficult part for me was to learn not to rest my hand on the shift lever; the microswitch was pretty sensitive and I could accidentally put the clutch in at the wrong time!

  • avatar

    Interesting series. It seems that the low-hanging fruit have been picked by now so I wonder about the subject of the next editions. Here’s my take on the articles:
    – 996: I left a longer comment over there, after just driving a 996 over the weekend. In a nutshell it reached its objective of making a huge profit for Porsche while the only clearly more desireable competitor from the area (Honda/Accura NSX) was a massive sales failure.
    – Cayenne V6: I hate all SUVs and the V6 was particularly pointless as a Porsche but it sold well enough.
    – 914-4: should have been sold as a VW like it was in Europe.
    – 911s 2.7: How many of its contemporary competitors have survived and which ones of those would be clearly more desireable and trouble-free today?

  • avatar
    DC Bruce

    Think of the thermal reactor as a catalytic converter without a catalyst. The idea was to burn up any unburned hydrocarbons coming out of the engine.

    The first Mazda rotaries (RX-2, RX-3) had one (1972). In order for the reactor to work correctly, the engine had to be run very rich (with the expected adverse effects on fuel economy) to provide a sufficiently fuel-rich exhaust, and the converter needed to be located as close as possible to the exhaust manifold in order to have the exhaust hot enough to light off. With the Mazda, whenever you shut the engine down, you could hear the reactor clicking and cracking as it cooled down. (I owned one.)

    Jack is certainly correct; this is not something you want to hang on an aircooled engine.

    • 0 avatar

      Corvair enthusiasts sometimes get to dreaming about what a third-gen Corvair would have been like. Maybe it would have been a nightmare. Imagine all these issues, with GM trying to address them. As it was, adding an air pump to the Corvair in ’68 required GM to take air conditioning off the option list, because engine temps were too high.

  • avatar

    Since the old man let his punk kid put the engine where it should never be, the 911 has been a mortal sin.

    The Swiss (or maybe the Danes, I forget) required weights in the nose of the 911 to try to make it sorta safe to drive – by the incredibly loose metric of the day.

    The 911 is still an embarrassment all these years later. Turn HAL off in a new TT and even Schumacher would stuff that POS in a week.

    A Panamera TT is a “real” Porsche.

Read all comments

Recent Comments

  • Lorenzo: Yes, they did. But they overpriced them and they didn’t sell. Thought they could get the same margin...
  • Marty S: My second car was a 1972 Grand Prix. Never realized the Stutz was built on that platform. I think I like the...
  • mcs: A medical facemask can help keep bugs out, but not in the way people expect. It discourages them from touching...
  • Art Vandelay: Still looks better than the Cyber truck
  • Art Vandelay: Normal folks are past it…bud

New Car Research

Get a Free Dealer Quote

Who We Are

  • Adam Tonge
  • Bozi Tatarevic
  • Corey Lewis
  • Jo Borras
  • Mark Baruth
  • Ronnie Schreiber