Deconstructing Technology, Go-Fast Technology, Hooniverse, Pushing Boundaries

The badge says DAF Variomatic. It’s a racing transmission.

Huron 4A Cosworth DAF Variomatic, by Wouter Melissen, via UltimateCarPage

It was a rainy Tuesday when I got a tip from Monkey10is that DAF had a history of racing. A machine I’d never heard of called the Huron 4A Cosworth DAF Variomatic. A quick search turned up an article by Wouter Melissen. Real enough. That’s where I found the first picture. Seems DAF already had some experience in Formula 3. Never mind their reputation for making innocent-looking two-cylinders named Daffodil. Wikipedia noted, quote ‘interesting’ low speed behavior when ice was around. And it’s an open secret that at top speed, slowly releasing the gas will make Daffodil go faster instead of slowing down. But I was more interested when Wouter mentioned an AWD DAF 555 prototype in passing. As if such a thing can be mentioned in passing.

DAF 55, by Anrie, via Wikimedia Commons

It was time to go to the archives. Google Translate detected as Russian, so I had to switch it over manually to Dutch. Before the Huron, a DAF 55 completed the London-Sydney Marathon. The 555 was built in parallel with DAF’s open wheel experiments, and used the same F3-spec of the Variomatic along with Gordini and Lotus 4-cylinders that would give the rubber bands more than 63hp worth of slip to limit.

The AWD 555 was built by the de Rooy brothers in three weeks using notes from the back of a cigarette packet. An old test report said they put engine transversely where the passenger would be, the transmission where the driver would be, the driver in the middle with a chain back to the steering column. Is there nothing de Rooys wouldn’t do? They made it switchable betwen 2WD and AWD.  They could have 4-wheel traction or avoid getting busted down on a time penalty. But the biggest shock was the spider differentials front and rear. BMW 2002, of all things. Later versions put the engine back in the front, and the driver back on the left where he belongs, but another diagram found on confirmed the crazy layout of the ‘bump’ car.

DAF 555 AWD ‘bump’ car, via

I went for a fresh cup, mainly because I needed a napkin to do my own scribbling. I’d expected a belt drive for each wheel, two Variomatics, eliminating the dependent relationship of spider gears, where revs spike when a wheel spins and you need three diffs. Instead, the belt drives replaced the transmission and the center diff of an otherwise standard path from piston to tarmac. The AWD was a red herring, and a moot point anyway because the FIA banned it. The real benefit of that CVT was keeping the lump in its powerband, not so much the finer points of vehicle dynamics. The DAF racers could have more power, more of the time, and pull a gap everywhere but the peak.

From a stoplight, a Honda in second gear will beat a Corvette in 7th.

Low end power sells cars, top end power wins races.

On the other hand, it’s easy to see how skimming a couple of percent here, a couple of percent there, and all of a sudden you’re losing ground instead of gaining. But things are never that simple. If you get rid of the need to pull at the low end, idle, or even rev up smoothly, an engine can make a lot more power in a very narrow window.

It all came together in 1993. Hub Van Doorn himself, who founded DAF and created the Variomatic, helped the Williams Formula One team develop a belt-drive CVT. It was enclosed to prevent slipping in the rain, beefed up for the power, tested, and banned by the FIA before it could ever race.

Not to be confused with the Weismann gearbox.

Williams FW15C, via RET Monitor

In this game, any time they make up new rules just for you, you’re doing well. Maybe a little too well for the people who would rather keep you on the straight and narrow.

I never reveal my Sources:

[1] Monkey10is

[2], article and images by Wouter Melissen

[3] Wikipedia – Daffodil

[4] Wikipedia – Variomatic

[5] DAF 55 – Wikimedia Commons

[6] – Great galleries of vintage DAF photos

[7] Motorsport Magazine, Page 36, 1972

[8] – make sure to scroll through every single fender flare

[9] Part 2: The Perfect Gear

[10] Race Engine Technology – Formula One CVT Part 1, Part 2

  • Dearthair

    Okay, this is one of my favourite articles we’ve had. That’s deliciously batshit insane. Mid-mounting an engine in the car, transversely, in the passenger seat, just because it might work better that way… that’s just delightfully nuts.

  • CruisinTime

    Sounds like they were having a blast working out the bugs of this little car.

  • The Rusty Hub
  • So you’re saying I should race the Variomatic-equipped Volvo I bought a few weeks ago? I was hoping to save it for next year’s much-rumored LeMons open road event instead.

    • Dearthair

      Wait… THAT is a Volvo? Tell me more of this.

      • It’s a 1976 Volvo 66 GL sedan, the only one in the US (and presumably North America). There are also two 66 GL Estates (wagons) here, a nonrunning one in Oregon and a restored one in Vermont which belongs to the director of the DAF Club of America. Mine has been in the Seattle area for about a decade, although I only learned of its existence when it turned up on Craigslist a few weeks ago. It’s this car:

        It’s pretty much a rebadged DAF 66, built shortly after Volvo’s hostile takeover of the company. Here’s a driving review of the Estate in Vermont:

        • Rover 1

          I think that a copy of the decal on the rally car windscreen would work quite well on your car (or any 66 for that matter)

          ‘Dutch National Daf Team’ does have a certain ring.

          Even if you’re not a Dutch National.

  • John L. Pagel

    Here is a CVT racecar, call it Variomatic if you will. It is powered by a 700cc Yahama motor and is perhaps the fastest(albeit fragile) LeMons cars there is. The Belt CVT allows the motor to be at its power peak of 9000 rpm all the time and the car is light as hell.

    • Variomatic-equipped car my a….

      Oh, wait, Balto is awesome. Never mind.

  • Tomsk

    Here’s the Williams prototype in action.

    • Innumerable bonus points if anyone can dig up actual laps.

    • Despite owning three vehicles with CVTs, I have to admit that from about the 0:50 point onward I was silently pleading for the driver to just pay attention and shift to a higher gear.

  • Batshitbox

    What a daffy idea.

    • Vairship

      It’s a little daffed, but not crazy!

  • Fuhrman16

    Interesting. I wonder, if the FIA hadn’t banned the F1 CVT, would we see them as exotic and desirable, the type of thing one would get in a super car rather than the misery device one is forced to get in a fuel sipping econobox?

  • nanoop

    From the comment of reference [10] pt.2: “[Coulthard] was surprised by the engine braking effect by approaching corners at max. engine revs w/o torque interruption” – I never thought of that! 90min at 15krpm…

  • discontinuuity

    Minor detail: the DAF had a four-stroke engine:

  • bigredcavetroll

    Anyone here ever owned a turbocharged car with a CVT?

    • My CVT-equipped KV Mini 1 uses a supercharger to pressurize the fuel tank (and only to do that), but this is as close as anything of mine gets.

      • bigredcavetroll

        Does it/how much does it heat up the fuel?

        I’ve always thought it would be interesting to have a car with a turbocharged engine and a CVT. The sensation of coming on boost and staying there seems like it would be unique.

        • Not by any significant amount. It’s more of a gentle breeze from the crankshaft-driven cooling fan that’s routed through some tubing to the tank, but that is technically enough for even the manual to call it a “Circuit d’air surpressé” in the schematic. It’s connected via a compensation circuit both to the tank and to the top of the sight glass and serves as the only supplement to gravity for feeding the fuel to the carburetor.