One of the greatest cars to emerge from Porsche in the mid-’70s, and one which helped legitimize the turbocharged engine as a credible racing motor, was the 935. A stretched 911 Turbo, hardened for sprint and endurance racing, with upwards of 850 horsepower, a four-speed manual, no aids, and a fraction of today’s downforce: a recipe that is enough to make most racing drivers tremble. With a cautious approach and a respect for the limitations of the car, Ulli Andree learned what it takes to master one of the fiercest, fire-breathing GT cars of old. Andree is a pro-am racer in both GT and touring cars as well as the director of global communications at Recaro,
Andree, now 52, grew up with the 935 as a car dear to his heart. As it rose to prominence during his formative years, it left an indelible mark upon him. Fast forward 40 years, and he was able to realize a childhood dream when Kremer Racing‘s current owner, Eberhard Baunach, offered him the chance to sample their infamous Jagermeister-liveried 935 at the Nürburgring Grand Prix Circuit in 2013. Recently, we were lucky to sit down with Andree to talk about his experience.
You can’t switch off that part of your brain that tells you ‘you’re driving an irretrievable, immensely expensive classic race car,’ so it’s best not to take a chance. — Ulli Andree
P: How did you get acquainted with the car?
A: I knew Eberhard and his team from the German Endurance Championship, which I won outright in 2012. We thought it would be a great opportunity to have the reigning champion race this very special car. For me, it was a childhood dream come true, since I saw these Group 5/IMSA cars racing in the ’70s and ’80s as a kid/teenager. Prior to the event, I was invited to the Kremer workshop, which is based in my hometown of Cologne, to learn the car’s functions and get a proper seating position. However, the Recaro seat did fit almost perfectly without the need for a change and compared to today’s race cars, the 935’s gauges etc. are rather basic.
As a product of a bygone era, the 935 K3 is still rather rough around the edges — brutal, really. Imperfect ergonomics, unassisted steering, and a lack of electronic-aids make it a real workout. However, this K3-spec car enjoys a few improvements over its predecessor — namely a twin-turbo setup. Though having two snails softens the power delivery and sharpens response, the power is monstrous, and enough to spin the wheels in most gears. As Andree had spent most of his career in modern cars, he had to tread carefully to avoid being bitten by this old-school brute.
P: What were your first impressions?
A: Adjustment even started before the get-go, since the seat is not in a straight line to the pedals, which are displaced to the right a bit. Thus, from your hip downwards, you have to try and curve your legs towards the pedals. This arrangement, by the way, is necessary due to the gearbox mounted upside-down to lower the center of gravity.
Getting out of the pits, you notice that the forces you need to apply to the clutch are significant. Once running, the steering is not too stiff and it provides you with a lot of feedback on the track conditions and what the car’s intentions are.
P: Have you ever driven something so heavily turbocharged before? What did you have to change in your style?
A: I have raced various turbocharged cars, but nothing as old-school and powerful as the 935. The 935 K3 is quite a brutal car with enough power on high boost to easily break the rear end away. To get the best out of it, I always felt — and that was confirmed by 935 pilots from the past — I needed a smooth driving style, which is the case with many race cars. This suits me anyway, because I never threw cars into corners like a madman unless I had to.
This smoothness, or “round style,” as Ulli puts it, helps in two specific areas. The front axle is often the limiting factor, as it doesn’t have much weight pressing it into the asphalt, so avoiding understeer is a challenge. Additionally, the amount of power is enough to unstick the rears; they’re even torque-limited at higher speeds, so a gentle right foot pays dividends here.
P: How did you nurse the front axle?
A: [It has] immanent 911-like handling depending on the fuel level. Remember, the reservoir sits right underneath the front bonnet and allows for a 120-liter fill, which I burned within less than one hour. So rushing down start-finish, Turn 1 is a right-hand hairpin and you have to brake from 175 mph down to 38. With a full tank you don’t have a problem with exactly braking towards the apex; no locking the front wheels, no understeer. The lower the fuel level, the more you have to apply trail braking to avoid the front wheels locking.
Also, it’s a good idea to brake fractionally earlier to avoid understeering at the turn-in point, since once that happens, the front wheels are in search of grip and start to slide. At one point, the front wheels find grip again immediately and provoke an instant oversteer. Once the grip ceases, this happens rapidly and counter-reactions at the wheel have to be swift, to say the least.
Smoothness also plays a part in administering the power efficiently. On high boost, the motor has no problem roasting the rear tires, so a delicate application of the throttle is a must. Fortunately, the technology pushed forward with the K3 cars made life a little easier in this department.
P: What were the car’s strong points?
A: The car’s strongest point, in the truest sense of the term, is power and torque: 800+ hp at 8,000 rpm and some 542 lb-ft of torque at 5,500 rpm! At just 2,300 pounds of weight, this gives the driver a real kick in his lower back, and the start-finish-straight at the Nürburgring has never been shorter. What really helps a great deal here too are the characteristics of the 3-liter engine with two smaller turbochargers instead of just one as seen on the K2; the throttle response on the K3 is much more direct with much less turbo lag. Also, due to the K3’s air-to-air intercooler, it maintains its maximum output throughout the entire race, while the K2, fitted with a water-to-air intercooler, loses some of its power as the race wears on and the water temperature rises.
While Ulli didn’t race the K2 himself, he followed one for one lap while driving the K3. This short time behind the predecessor was enough to show that the K2 has less horsepower, is much less responsive, required more work at the wheel, and had a harder time determining when to apply full throttle.
P: With that amount of power, was it difficult administering the power cleanly?
A: The K3 runs a rigid rear axle. When I first thought about this, my initial assumption was that the car will probably understeer heavily. But this didn’t really prove to be real when you stick to those rules I described earlier. The trick to being quick is not to go sideways – that’s common knowledge for road courses – to avoid losing momentum. Even with 800 hp, you lose momentum when power oversteering at a turn’s exit. So, you use the throttle progressively, and once the car is positioned fairly straight, you apply full throttle. That way you’re on the safe side and it works very reliably when you’re not under pressure.
P: How was the gearbox?
A: Despite its 4-speed-gearbox, you never have the feeling of a missing additional gear. Because the gearbox is synchronized, as was typical for Porsche race cars of that era, you cannot shift as quickly as you can with a dog ring ‘box, but gear selection is very precise so the chance of a mis-shift is low.
P: How did the car behave once it started to slide? Was it manageable beyond the limit?
A: Of course, once you overshoot the lateral-guidance limit of the rear tires you have to be really quick with counteractions at the wheel and via the throttle. What’s even worse is that once the front tires find grip again after some turn-in understeer, you immediately encounter a snap-oversteer, because the rear bears less load due to the dynamic shift in axle-load and the changing pitch.
In my first outing, I had a low-speed spin without contact due to this understeer-oversteer-characteristic I described. My turn-in speed was a bit too high and I got quite a heavy understeer. Then, I tried to open the steering a bit to give the tires some relief and to find grip again, which happened so abruptly that the back end couldn’t cope.
P: How does it compare to a modern racing car?
A: Benefiting from its wide rear wheels and the rear engine, the 935 has superb grip out of virtually every corner, at every radius, at each speed level. So basically, when you follow today’s GT3/GTD cars with ABS and traction control they seem to corner as if running on rails. The 935 is always in action since it has no such devices and some 200-250 horsepower more than a current GT3/GTD. Nevertheless, I learned that if you respect a 935’s characteristics, and can adjust to different circumstances, even a 935 can be mastered.
There are not so many modern cars around which have comparable power. However, today’s aerodynamics, brakes, tires, chassis, driving aids etc. make up for quicker lap times with some 200 hp less than a 935. What’s still amazing is the 935’s top speed at the fastest point of the Grand Prix circuit of the Nürburgring is more than 175 mph — compare that to a modern GT3/GTD car’s at 147 mph in the same section!
Don’t get me wrong, the K3 develops a fair amount of downforce through its body shape and wing, but there’s no underbody generating additional downforce like on modern GT3/GTD cars. Unfortunately, there are no figures existing since, believe it or not, the K3 never saw a wind tunnel. The creator of the K3’s body panels, Ekkehard Zimmermann, simply had the right feeling for aerodynamics and success in the late ’70s and early ’80s proved him right.
So yes, when, for instance, you approach Veedol-Chicane at a top speed of almost 180 mph, you hit the brakes real quick and really hard. Then, with reduction of speed, while downshifting, you gradually taper off the brake pressure to adjust to the lower downforce (due to deceleration). When you hit the brakes hard, the car provides a good sense of confidence, because it is very stable at high speeds and under braking when you sort out the brake balance right.
Compared to today’s race cars, the 935 doesn’t produce a great deal of downforce, also the brakes of today’s GT and touring cars allow for later braking points. But hey, we’re talking about a car from 1980, which is almost 40 years old.
Even though it’s not as fast in the corners or the braking zones, did you find it more or less physically tiring than a modern GT3/GTD? Is there more or less to think about?
Well, the 935’s limit has usually been the close-to-production chassis, which was developed from the road car, even though Kremer made it stiffer. In fact, it still twists a bit under the massive power and torque, even though being reinforced. So in the long term, and from my perspective, a modern car with downforce is physically more demanding due to higher cornering speeds because of modern tires, for more mechanical grip combined with aerodynamic grip. But since the 935 has no power steering, it is still exhausting in a way. Also, you can’t switch off that part of your brain that tells you “you’re driving an irretrievable, immensely expensive classic race car,” so it’s best not to take a chance.
Other than that, there’s not so much to think about. For example, there’s no dash you can scroll through all sorts of pages to let you know about every little detail. Plus, you have to manage three pedals with two feet. In the end, it’s you, the rev counter, and some other analog gauges for oil or boost.
While the 935 still stands as one of the more foreboding racing cars in recent history, this detailed account proves that, with an appreciation of the car’s limitations, a talented driver can master it. Due to the amount of mechanical grip, the 935 can corner at remarkable speeds if treated with some respect, but due to the disparity in tire widths, the weight distribution, the lack of electronic systems, and the sheer power, the car is not one that can be mistreated without repercussion.