924 vs. 924S vs. 944: What’s the Difference?

This article was originally published in March of 2018.  It has shown to be one of our most popular articles, so we are editing it a bit and republishing it.

In amongst the 944 series you find the 87-88 924S.  The 924S isn’t rare, isn’t a classic (yet) and isn’t all that popular.  The 944 fender flares – “hips” –  give it a more aggressive look and the slightly wider track makes it seem more desirable.  I have had a lot of people say, “I just don’t like the body on the 924S…I like the 944 so much better.”

Understanding the history of the model helps you to understand the evolution of the model.  The early 924 came to America in 1977 and stayed through the 1982 model year.  In 1983, America got the new 944.  However, the 924 remained popular in Europe and in other areas around the world, but the 2.0 Liter 924 was finished in the U.S.  With sales of the 2.0 924 continuing, Porsche continued to make the car for sale outside America.  However, the Audi/VW 2.0 Liter engine block was discontinued after the 1986 model year, so Porsche had to decide whether to kill the model or do something different.  They then decided to re-engineer the driveline of the 2.0 924 to take the 944 driveline, and the 924S was born as a 1987 model, then brought to America as an entry-level Porsche.  That explains why the 924S does not have the dashboard/interior, steel gas tank, trans mounting and front suspension upgrades that are found in the same year 944.  

So other than the wider fenders, what are the differences in the two models?  Is there more to it than just fenders and track?  Of course there are other differences, but What are they?

Image result for porsche 924The early 924 is “the same thing, only different.”  Those without experience with the different models often ask, “can I put a 944 engine in an early 924?” or such questions about drive train.  As far as engines go, the short answer (and the long answer) is basically “no.”  You can transplant any engine into anything with the proper application of engineering prowess and cubic dollars, but as far as a bolt-in, they are just not compatible.  The front crossmember, steering, sway bar setup and engine mounts are just different and making the change doesn’t make sense.  (We have never been asked about putting an early 2.0 Audi 924 engine in a 944…wonder why?)

Image result for porsche 924 snailshell trans
’79 924 “Snailshell” 5-speed transaxle

The early 924 used a version of the Audi transaxle in all cars except the 1979 model year. Prior to 1979, the 924 used a 20mm input shaft instead of the later 25mm input shaft, so the drive tube on the 924 NA cars is the smaller shaft that is incompatible with later 944 and 924S transaxles.  The 931 (924 Turbo) used the 25mm drive shaft, so transaxles in them share with the 061 transaxles of the early 944.

In 1979, the 924 got the “snailshell” transaxle with a different drive tube, different shift mechanism and different rear suspension.  These transaxles were not great, not well received and therefore discontinued after the 1979 model year, opting to go back to the Audi unit design.  This was carried forward to the early 944.

Image result for porsche 944 1984When Porsche debuted the 944 in 1982 (1983 model year), it was met with rave reviews.  People lined up at the dealerships to buy them.  The flared fenders, 2.5L normally-aspirated engine and sleek lines made it a hit.  The obvious fender flares gave it a more racy look than the previous 924, and the Porsche-designed 2.5L 4-cylinder engine replaced the underpowered 2.0L from the 924.  At about 150 HP, the new engine provided adequate power for the day, but the 50-50 weight distribution and four-wheel disc brakes were just what the doctor ordered.

The suspension and brakes were carried over from the 931.  The rear suspension used steel trailing arms and “banana arms” and used a different rear shock than later models.  The banana arms were redesigned in aluminum for the Series II redesign released in the middle of the 1985 model year and remained through the end of the series, including the 924S.

imageimageThe first major redesign in 1985 – designated as “Series II” cars – are typically called “eighty-five-and-a-half” cars.  These are easily identified by the new dashboard and console featuring an oval gauge cluster.  One of the major differences in the Series II cars is the transaxle mounting – the transaxle is held in by a single top-center mounting instead of the older double-side mountings from the earlier cars.  Changing transaxles between early and late model years can be a challenge, but that is for another day.  The fuel tank in the Series II cars is larger and made of plastic, and the front control arms went from steel to aluminum with much more expensive ball joint replacement costs.

Even though the 924S was produced between 1987 and 1988, it kept the older style interior, dashboard and console.  The transaxle also retained the double-side mounting and steel gas tank from the earlier cars, as well as the steel front control arms and VW Rabbit lower bar joints.

Image result for porsche 944S engineAs the 944 Turbo (951), 944S with its dual-overhead-cam design, the 1989 2.7L engine and the 944S2 3.0L engines evolved, the models became more sophisticated and more expensive.  Limited slip differentials were offered in all models, although there was some mild gearing changes in the various model transmissions.  Cruise control, power door locks and other options were added over the years.

As with most Porsche models, the option list and differences increased as the model matured.  In fact, the 968 was originally going to be the 944S3, but when designers and engineers figured out that the new car would be vastly different, the designation “968” was assigned.  It was produced between 1993 and 1995.

While all three models produced between 1976 and 1995 share many parts, it is best to double check to be sure that there is compatibility between years.  As a side note, our 924S944.com 1982 924 race car has a 924S rear suspension, 924S front suspension with reinforced steel control arms, 944 transaxle with the 25mm input shaft and drive tube mated to a 924 2.0L engine and a 931 clutch – all legal, by the way.  Brakes are from a 924S with all brake line rerouted for the front-rear 944/924S braking system.

That is another difference between the early car and the 944/924S models – the brake system.  Dual brake systems were actually a new idea in the late sixties and early seventies, and the conventional thinking during the engineering of the early 924 in the early 70’s was to have a diagonal braking system.  This means that instead of a front-rear dual system, the brakes were divided between Left Front/Right Rear and Right Front/Left Rear, so that if you lost one circuit, you would have one front brake and one rear brake.  While this made sense with the front disk/rear drum systems of the day, things changed as the braking systems matured and four-wheel disk brakes were introduced.  Engineers found that by varying the chamber sizes in the master cylinder as well as the individual piston sizes front and rear, better calibration of the front/rear bias could be attained.  So just slapping later model brakes on an early 924 may not work as desired.

Questions?  Just ask.





Author: Kevin Duffy, 924S944.com LLC, DeLand, FL

After retiring from a career in Law Enforcement, Kevin Duffy turned his attention to one of his passions, Porsche 944's and 924S's. He owns 924S944.com LLC in DeLand, FL, rescuing and restoring forgotten Porsches, bringing them back to a useful life. He is especially interested in the rare-but-beautiful 924S Special Edition. He can be found at Porsche Club events, including track days, tours and shows, as well as other car-focused events around the southeastern United States.

9 thoughts

  1. I am thinking about buying an 87 924S with under 20,000 certified miles. Would a dyno tune bring the horse power up from the tuning down the US required at that time?Can you recommend some performance parts that would work well with that car?

    1. The US 87 924S is a 150 HP engine. Without going into the engine and changing pistons for more compression, there is actually little that you can do to increase horsepower. At the dyno they would want to tune the computer (DME) but these are not adjustable. A good chip replacement could add some power and cure some of the US performance issues, but by much. As a comparison, I built an ’87 engine with 10.2 compression pistons (1988), forged rods, lightened and cross-drilled crank, WEB cam and a little porting – and boosted it to 172 HP. Now a 22 hp gain is significant, but not necessarily the boost that you may be looking for. The Euro-spec engines had a 10.6 compression ratio which made a big difference when compared to the 9.7 compression US engines, and replacement pistons are available to go in that direction.

      I would suggest the only power modification being a chip for the DME. They are not too expensive and they do make a difference in performance. However, there is little that you can do short of building a new engine, and even then the gains are not that great.

      Remember that in 1987, 150 HP was not too bad – even the 1987 911 Carrera was only about 225 HP. But with today’s compact SUVs showing 200-350 hp, the 924S seems a little weak.

      A 924S with miles that low is a time capsule – my suggestion is to keep it as stock as you can and enjoy it for what it is. These cars are increasing in value every year, and a low miles, totally stock 924S only increase in value.

      Good luck with it. Let us know what happens.


    1. Thanks for the question…the decision comes down to parts availability. There are a lot more 944’s out there for parts. 931 parts are harder to find and can be more expensive. The 931 is going to be slightly lighter than the Series I 944; the 944 has a wider track.

      That said, the 931 was the development mule for the first 944 models, so there are many similarities. Power is about the same, but the 944 2.5 is simple, NA technology with a lot of parts availability. Unless you get a great deal on a 931, my money is on the 944.


  2. Hi…I own two early 944’s. One is a 1984 that I have had for many years, and I just recently purchased a very clean and good looking 1983 for real cheap because of issues. The engine and suspension matters I have taken care of and it runs superb now, but the tranny needs to be rebuilt or swapped. I am not against rebuilding, but my first choice is to fine a good used unit, so I have been shopping. I found a 1987 924S unit that I have been told will work in my 944. I am trying to confirm this, and is it a smart move? I understand the gearing is different, a little more fifth gear speed I understand. What about mileage, speedo etc?
    Any help would be vastly appreciated…I am in WA state…

    1. Frank – The 924S transaxle is the same outward design and will work in your early (Series I) 944 without a problem. The only gearing difference is fifth gear, and you will not notice any difference in the odometer or speedo. So you know, rebuilds on transaxles are pretty expensive – a couple grand just for the parts. There are plenty of used units out there to choose from; the only difference is in the mounting of the Series II 944 is different. As a side note, the 924S gearing is preferred for racers as there is not as big a drop in RPM from 4th to 5th, making is more desirable on track. Best of luck!

  3. I was looking at getting either a 924 or 944, im a huge ford/mustang guy so one of these cars is something completely foreign to me. I dont care about power because im just going to putz around the local track on test and tune days Is there anything body/mechanical wise to look out for in these cars? Sort of like how foxbodys are bad for strut towers and torq boxes do these have a “oh yah 944s are really bad for x?”

    1. The 944 or 924S cars are strong chassis, great handling cars. Their strong point is handling, which is good because the power isn’t there. And there are no “power adders” that are economically viable for them – unlike the mustang V8s. The two mechanical areas that need attention are the timing belt/water pump service and the clutch. The timing belt service should be done to avoid a broken belt situation and bending valves, and the clutch can be a time-consuming expensive proposition, so focus on those when looking at cars. Avoid the 2.0L “early” 924 as they only have about 100 hp and can be difficult to find engine parts for (76-82). I am not a big fan of the turbo cars only because the added heat and complexity can make them difficult/expensive to maintain.

      With all that said, I do like the 924S as it has the same engine and driveline as the 944, but are lighter and more aerodynamic. You can fit 7″ and 8″ x 16″ wheels front and rear with the same size tires as the 944 with only 2″ narrower track. For track days, install larger (944 turbo) sway bars, 250-300 pound coil overs on the front and Koni adjustable shocks for a great suspension. Lower it about an inch – makes a huge difference on track. Also the 924S is somewhat “unloved” so purchase prices are lower.

      Let us know if we can help.

What do you think?