Enlivening Souls

Behind the wheel of a beautifullyrestored 1970 914-6 “2.5.”

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June 30, 2017

Modern cars are fantastic. And modern sports cars are glorious triumphs of science and engineering. The pages of Excellence are filled with the merits of these modern marvels, with spectacular new car introduction after new car introduction. And the modern technology these machines contain is spectacular. Air bags, anti-lock brakes, stability control, Bluetooth, parking sensors, active aerodynamics, and on and on. Do some of these technologies prevent accidents? Certainly. Do some of them save lives? Without a doubt! So I concede that all of this technological progress is immensely positive.

But when we see manufacturers working hard on their computer-controlled electric power steering algorithms to introduce some greater semblance of “road feel” back into the driving experience, or we see Jaguar and others implementing a computer-synthesized artificial burble into the exhaust note on deceleration, what is that telling us?

And when we see some well-educated consumers shunning Porsche’s excellent PDK semi-automatic transmission for a three-pedal manual gearbox car when any purely rational reading of datasheets tells you that PDK is, without question, the faster and more efficient way to shift gears, what is that telling us as well? What are these manufacturers trying to do? What are these buyers of three-pedal sports cars searching for?

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The answer: The immensely satisfying grin-inducing experience of driving a purist, minimalist sports car. The reason there remains a desire for this experience among some enthusiasts became clear to me as I was hustling Tom van Overbeek’s restored 914-6 up a winding mountain road in the hills near San Jose, California.

I should clear up some potential name-related confusion: Yes, Tom van Overbeek is the successful northern California amateur Porsche racer. His blue #02 Spec 911 race car (which was featured in the August 2016 issue, #238) is likely one of the winningest amateur 911 race cars on the West Coast (and perhaps in the whole country). And yes, Tom is also the father of professional racer and regular Excellence contributor Johannes van Overbeek. But Tom’s interest in Porsches doesn’t end at ones built for the race track.

The beautiful black 1970 914-6 you see on these pages is the fourth 914-6 that Tom van Overbeek has owned. Coincidently, his first one was also a black 1970 914-6. He recently shared an amusing father/son story with me about that first one and how, one evening, it came to be totaled. The story involves the young, not-yet-licensed-to-drive Johannes.

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There they were one evening, driving in the hills behind their Oakland home, young Johannes behind the wheel, father teaching son how to drive. They crested a small rise and were immediately engulfed in what appeared to be smoke or fog or dust. A large dead tree had just fallen across the road an instant before! Dust and tree limbs were everywhere.

Johannes swerved and avoided a head-on impact with the tree, but found the serious ditch at the side of the road instead. Unfortunately, the lovely 914-6 was a total loss. But father and son were unhurt. Police arriving at the scene questioned the elder van Overbeek about the accident, with him answering questions with the artfully imprecise, “Well, we were driving along when…”

On that fateful day in 1987, the world lost a 914—a 914-6, at that. Thankfully, the van Overbeeks were OK. And the loss of the car? Some sports car fans might say, “No big deal. It was just an old 914.” After all, more than a few enthusiasts still treat the 914 as an unloved stepchild in the Porsche family. But, as I learned from behind the wheel of our feature car, those who take this view of the 914 are dead wrong!

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Restoring a Beauty

It’s been 30 years since that unfortunate day in the Oakland Hills. In the three decades since that car was lost, Tom van Overbeek has owned more than 20 Porsche 911s, scored dozens of racing victories and accumulated thousands of hours of experience learning about and working on Porsches. He brought all of that knowledge and car wisdom to bear on this 914-6 build.

The project started innocently enough. As so many of us do, bored one morning, van Overbeek was poking around the online Porsche classified ads—and there it was. A genuine 914-6 with factory GT bodywork fitted by Brumos Porsche, the right period correct details, the correct wheels, and so on. Though van Overbeek lives in northern California and this 914-6 was in Florida, he checked in with some contacts in the Sunshine State.

A few phone calls later, and van Overbeek had made arrangements to have the car inspected by a renowned Porsche expert. The car was declared to be good after its once-over, and a deal was struck. Another call or two was made, and an auto shipping company has the 914-6 loaded and en route to California. It all seemed to fall into place so easily.

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When the car arrived at van Overbeek’s home, he eagerly jumped in its driver’s seat for a test drive. But being an experienced car guy, he knew enough to do two things you always do when you take an unfamiliar old car for a test drive. First, always bring your cell phone. And second, always head out up the hill from your home, so that if/when the car fails, you can coast home downhill.

Sure enough, van Overbeek is perhaps three miles along on this drive in his new 914-6—and the shift rod falls off! But the shift rod is just the tip of the iceberg. A closer inspection of the car reveals myriad issues: a broken anti-roll bar link, seized bushings, a bent strut, no steering rack boots, and on and on. Each mechanical system he inspects is found to be sorely lacking. He removes the engine to make some basic oil leak fixes, but he finds that a simple hand cranking of the engine is rough and balky, indicating a potentially bent crank. It becomes clear that a mechanical restoration is needed.

Thankfully, once van Overbeek removed all of the mechanical systems—the engine, transmission, front suspension all came out—he found that, apart from some surface rust on the bumpers and the to-be-expected rust in and around the battery area, the car’s body was solid and remarkably rust free. The deep black lacquer paint, probably applied some time in the last ten years, was also in remarkably good condition.

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While the correct five-bolt 15 × 7-inch front and 15 × 8-inch rear Fuchs alloy wheels went off to Harvey Weidman’s Wheels in Oroville, California for a complete restoration, van Overbeek turned to local Porsche legend Jerry Woods and his firm JWE Motorsports in Campbell, California for help with the engine and transmission. Van Overbeek would handle the needed brake, suspension, and interior work in his home workshop.

After consulting with Woods, van Overbeek settled on a rebuild that would transform the car’s troubled 2.7-liter flat-six engine—which a previous owner put in place of the original 2.0-liter six—into a 2.5-liter variant. He wanted that addictive high-revving quality found in the small short-stroke Porsche engines (stock 2.0 and 2.2 liter 911s all have the short-stroke 66-mm piston throw). He also wanted to give a nod to the 2.5-liter engine configuration run in Walt Mass’s IMSA-winning 914-6 of the mid-1970s.

One way to arrive at 2.5 liters would be to combine a 66-mm crank with a 2.7-liter cylinder. But that would yield a compression ratio of 7.5:1, which was way too low to produce good power. Woods and van Overbeek were after something in the 9.2:1 range. And the only way to get there would be via custom-designed pistons.

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Woods set to work with his computer-aided design (CAD) tools, and the finished design was put in line for production in Mahle’s custom piston operation. Alas, the timing was poor, and Woods and van Overbeek found themselves in line at Mahle behind some important NASCAR clients. Months ticked off as they waited for the needed pistons.

They used the wait time to line bore and prep the engine’s magnesium case. A set of 40-mm Weber IDPT carburetors were found and converted to IDA specs by Weber guru Paul Abbott of Performance Oriented in Chico, California. Carillo rods and GE-60 cams completed the engine package. The 901 gearbox was rebuilt, and a Guard limited-slip differential was added.

Once all the parts arrived and were assembled into a running engine, the 2.5 made a healthy 224 hp and 190 lb-ft of torque on the dyno. That’s 99 more horsepower and 59 more lb-ft than a stock 125 hp/131 lb-ft 2.0-liter 1970 914-6.

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When the wheels arrived back from Weidman, beefy Avon CR6ZZ radials were mounted, filling out the fender wells perfectly. The 215/60-15 front and 225/60-15 rear sizes created the right period look and, very importantly, had enough sidewall depth to serve as an essential part of the car’s suspension system and overall ride quality.

Test Drive Time

I drop into the driver’s seat and find that it feels surprisingly low. Tom van Overbeek rides shotgun. The pedals, gauges and other controls are all familiar Porsche 911 bits from the early 1970s. But this cockpit is smaller and minimalist; the engine occupying what might have been a passenger compartment. Two pumps of the throttle to prime the Webers and the engine roars to life with the unique snarl of an early air-cooled flat-six engine.

Now I get it; the engine is inches from my head. I hear each tappet, the timing chains, and the intake, and oh, that exhaust! With a vintage sport muffler, this car is loud. Van Overbeek admits that he probably should install a more “age appropriate” muffler one day—but not today. Man, this car sounds great! The GE-60 cams are considered to be mild race cams. So yes, the idle is a shade lumpy and athletic-sounding. Pulling away slowly to warm the car, the engine is surprisingly smooth at lower rpms but a bit like a dog on a leash, not entirely happy. It wants to run!

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We head out to the freeway. This 914-6 tracks beautifully, and its ride quality is surprisingly good. The deep sidewall tires, stock rubber suspension bushings, 140-lb rear springs, 18.6-mm front torsion bars (from a 911 Carrera 3.2), and 19 mm front anti-roll bar all work together superbly. This car is eager, nimble, but eminently drivable. While cruising at 3,700 rpm, the interior noise level is reasonable, and the engine is smooth.

After getting a nod of permission from van Overbeek, I run up to the 7,500 rpm redline in third gear. The 2.5-liter six accelerates smoothly up to 4,000 rpm, then the exhaust note builds to a scream and the engine responds with smile-inducing urgency. The engine is now quite loud, shrieking toward redline with that lovely air-cooled Porsche sound. Yep, I now understand the appeal of these early short-stroke engines. Wow!

Next, we reach our exit and head for less traveled hills east of San Jose. As soon as we hit the more challenging backroads, I immediately feel the paramount thing that differentiates these early cars from anything modern: Its acceleration, turning, and stopping are all executed with a near-telepathic immediacy that can only be had in a lightweight car. But I am feeling something else too.

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We know that the 914-6 and 911 share many mechanical components. The front suspension, brakes, wheels, engine, and transmission are virtually interchangeable. But in the 914, the engine sits in front of the rear axle, rather than behind as it does in the 911. Weight distribution in an early air-cooled 911 is around 38/62 front/rear. Freshly corner-balanced, this 914-6 has a weight distribution of 46/54. A more equal weight distribution results in a more neutral handling sports car.

You don’t feel the initial understeer as you would when you push a 911 into a corner with a bit too much speed. The 914 just turns like a go-kart. Likewise, trailing throttle oversteer is there with a 914, but not nearly as pronounced as it would be in an early 911. This car just carves through the turns.

The Verdict

As we complete our drive and head back down the hill toward van Overbeek’s home, I realize that this car is the perfect illustration of why so many of us love these early minimalist cars. This little black 914-6 delivers the wonderful purist driving experience that can only be found behind the wheel of something raw, light, balanced, genuine, and well sorted.

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Sure, the modern cars that fill the pages of Excellence are great triumphs of engineering. And no question, they even save lives. But cars like Tom van Overbeek’s lovely black 914-6 do something more. They enliven souls.

Also from Issue 248

  • 2018 911 GT3 Drive
  • The 996 in GT Clothing
  • Market Update: 964 & 993
  • A Rare RHD 1965 911
  • 1956 356 Speedster
  • TechArt’s 911 Turbo S-based GTstreet R
  • Buying a 996 Carrera 4S
  • Profile: Harald Wagner
  • 971 Panamera Tech
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