Dutch Ingenuity: the Story of a revolutionary DAF in RallyCross

"BvdV - The Dutch Engineer" (dutchengineer) 02/15/2018 at 08:02 • Filed to: daf, thedutchtooktheclutch, variomatic, rallycross, Embiggen challenge, Embiggen this, daf 555

30

37

In 1969, Dutch broadcaster AVRO brought RallyCross to the Netherlands, inspired by the British, as well as the fact that stage rallying was becoming too expensive. Shorty after this, a new star was about to rise in this sport. Or actually two stars, one of flesh and blood, and the other of metal and rubber.

The former was ex motocross rider and transport entrepreneur Jan de Rooy, who later went on to race trucks in the Dakar rally, mainly racing DAF trucks, where he earned the nickname ‘l’ours’ because of his posture. In rallycross however, he got the nickname ‘Ome Jan’ which translates to Uncle Jan, showing the role he had in the development of the sport.

After entering his first rallycross in a Mini, he soon switched to a DAF 55 Marathon for the 1970 season, which became the second rising star. This DAF 55 was powered by a 1290cc Renault-Gordini engine, which paired to the DAF’s Variomatic gearbox (a very rudimentary CVT, based on cones and rubber belts) proved to be a car capable of earning both national and international championships, especially in the hands of young Jan de Rooy.

Halfway into the 1971 season, however, he upgraded from the 55 to a DAF 555, as the 55 wasn’t always quick enough to keep up with the lighter Austin Coopers. Together with DAF engineer W. Hendriks, a DAF 555, a successful former group 6 rally car, was converted. Gone, however, was its front mounted engine, as well as its rear wheel drive. What hadn’t vanished was the CVT, it’s function and position had changed, though.

Looking a the picture above, it can be seen that the position of Jan de Rooy (who apparently used the same number as Kenny from the Block) is slightly awkward. The reason for that is that the engine and Variomatic were moved inside the cabin. Yes, that’s right, the driver was sitting next to the engine, and on top of the gearbox, necessitating a modification of the roof. This modification earned the car its nickname ‘het bultje’ or ‘the little bump’.

From the schematic of the drivetrain, it becomes clear that they rotated the Variomatic of the DAF 555 by 90 degrees, and moved it forward, to where the driver would sit. When mounted in its normal position, it acts as a differential between the two rear wheels. However, that functioning made it perfectly fit as a 50:50 centre differential and gearbox in one, especially as the 555 used a beefier unit stemming from a DAF Formula 3 car, meaning it could handle more power. The Variomatic powered the wheels though two BMW 2002 sourced limited slip differentials. On the other end of the drivetrain, next to the driver, was the same Renault-Gordini engine, and later 1800cc Ford BDA with round about 180hp.

So in short it was a 180hp, 4 wheel-drive rally car, with a CVT gearbox, giving it acceleration without shifting. Needless to say, it was much quicker than anything else, again earning Jan de Rooy some national and internation titles. It did have some downside though, as the driver position was rather awkward, and sitting next to the engine lead to a lot of heat being present in the cabin.

For the 1972 season, these problems were solved by moving the engine back to the front of the car, however still mounting it transversely. This solved the heat problem, while still using the Variomatic in the same way. It is not fully clear how the the engine was connected to the gearbox, however, I suspect some kind of shaft connecting the side of the engine, to the input of the Variomatic. The drivers now basically took the spot where the engine used to be, as they now were on the right side of the car. Another difference for 1972 is that Jan’s brother Harry will be driving an identical car, now with Camel as a sponsor. (Jan is quite the smoker, and often had sponsors related to that, Hofnar as seen on the earlier car was a cigar manufacturer, and later in his Dakar days he would run a Gauloises livery.)

This newest evolution of the DAF 555, with between 180 and 200 hp on tap, was so much faster than the other cars, that both cars had to start 5 seconds behind the other cars. Every race, and even then the organisers were thinking about furher penalties, as they were still able to win race after race. And they weren’t racing against some low-grade drivers, as Jan de Rooy and his brother regularly battled it out against rallycross legends like John Taylor and Stig Blomqvist, with many battles ending in the Dutchman’s favour.

After the succesfull 1971 and 1972 seasons, the FIA however banned the 4 wheel drive system used in the 555. This meant a move back to 2wd rallycross DAFs. Jan de Rooy, however, decided to continue racing the 555 in open-class races all around Europe, without an official sponsor, but just in the colour of his transport company, and his country, bright orange.

This would be the last races the DAF 555 would participate in, as some of its BDA engines were donated to rear wheel drive 55s and later to a DAF 66, called the tube-66 (after its tube frame), which was Jan de Rooy’s re-entry into the championship for DAF in 1974. He was supposed to continue racing that in 1975, however didn’t start the season. Later he went on to rallycross Escort RS1800s and Audi Quattros among others, before making the switch to driving trucks in rally raids.

As for the 555s, some of them were used for ice racing during the 1973 season, after which records of them stop. It is known that DAF produced four 555s for stage rallies, with license plates 70-76-MF, 70-77-MF, 70-78-MF and 81-89-SE. From these 70-77-MF, 70-78-MF and 81-89-SE have definitely been used for rallycross, as picture evidence of this has been found(and has been scattered throughout this post). According to some sources all 555s were even converted to 4 wheel drive rallycross spec at some point. Today, both 70-77-MF and 70-78-MF have been restored to their stage-rally spec, with both 70-76-MF and 81-89-SE dropping of the radar after their rallycross years. Surprisingly enough, 70-76-MF is also still registered, so hopefully is still is around in some form or other (there is no talk about it on forums). Jan de Rooy is rumoured to own 70-77-MF, while 70-78-MF is in the DAF factory museum. Apparently restauration of both, which took place at the same time, was a pain, as the floors were completely cut to bits for the rallycross drivetrains.

The uncertainty if 76 has ever been converted, 77 and 78 being converted back to stage-rally spec, and 81-89-SE being unaccounted for means that possibly none of the 4 wheel drive rallycross DAFs remain to exist today. Which is a shame, as it was a true marvel of engineering. Hopefully 81-89-SE is still hiding somewhere, waiting for a day to return to the sand and tarmac of the Eurocircuit, or 70-76-MF was converted to rallycross spec after all and kept that way. If not, I think my mission will be to someday build a replica of it, to remind the world of the wonders of Dutch engineering. Anybody have a racing Variomatic, DAF 55 Coupe body shell or BDA laying around?

!!! UNKNOWN CONTENT TYPE !!!

Without these brilliant sources writing this article would have been way harder, so special thanks goes out to the authors of these. (All sources are in Dutch, obviously.)

!!!error: Indecipherable SUB-paragraph formatting!!!

http://www.teamdafverzamelaar.nl/daf_555/daf_555.htm

http://www.racehistorie.nl/index.htm

AuthiCooper1300 > BvdV - The Dutch Engineer 02/15/2018 at 08:14

1

Good show, Mr BvdV. Good show!

Peter Monshizadeh > BvdV - The Dutch Engineer 02/15/2018 at 08:16

1

Wow, excellent write up. I never knew such a thing existed! I have to say, aside from the heat issues in the cabin on that first 4WD iteration, I would be more worried about the large, fast spinning parts right under the driver’s seat. Imagine if that went wrong...yikes!!

BvdV - The Dutch Engineer > Peter Monshizadeh 02/15/2018 at 08:22

1

Thanks!

I suppose they had some cover, to which they also mounted the seat. But I agree, still pretty tricky. The good thing about the Variomatic though, is that in case of a problem the rubber belt would probably give way first.

BvdV - The Dutch Engineer > AuthiCooper1300 02/15/2018 at 08:22

0

Thank you! I already knew quite a bit about it, so knew it was going to be a good story , but it was great to research the topic further and find out more about it .

AuthiCooper1300 > BvdV - The Dutch Engineer 02/15/2018 at 08:27

2

You are most welcome.

It is a lovely effort, but it is also excellent. First of all, it is an unusual subject (well, for most of ous outside the Netherlands); secondly, it has quite the right mix of humour and technical rigour; thirdly, it is nicely structured, and, in my opinion, very well written indeed.

You better start preparing another... now I want more!

BvdV - The Dutch Engineer > AuthiCooper1300 02/15/2018 at 08:36

1

Good to hear that you liked it that much!

Yes it’s quite the unusual subject, even here in the Netherlands, but having a passion for DAFs and quirky engineering meant it was a bit of a no-brainer for me. I tried to keep it light, while focussing on the interesting technical bits, as that is what makes the car, so I’m glad that worked well. As for the structure, I just stuck to time, as that is the w ay the modifications make most sense.

Well, I could do one on the DAF turbo-twin... or maybe something electric vehicle related (as that’s my field of engineering).

SilentButNotReallyDeadly...killed by G/O Media > BvdV - The Dutch Engineer 02/15/2018 at 08:38

1

Ever since I saw Alby Mangel’s World Safari at the Top Ryde Town Hall as a child...I wanted a DAF truck with its rubber band driveline. Now I want a DAF sedan to go with it....

BvdV - The Dutch Engineer > SilentButNotReallyDeadly...killed by G/O Media 02/15/2018 at 08:46

0

I want one too. Or 2 or 3... After I found out my great grandmother had a DAF 55 Coupe Marathon at some point, I’ve wanted one of those. Of course they are rare as hens teeth (any 55 Coupe is quire rare ). But I also want a 555 rallycross replica (but butchering a 55 Coupe shell is not something I dare to do. And I also want a resto-modded 66 Coupe... .

Looks like I need to buy one to start this madness, haha. Luckily they are relatively cheap here in the Netherlands!

AuthiCooper1300 > BvdV - The Dutch Engineer 02/15/2018 at 09:12

1

Both possibilities sound pretty good to me. I’ll keep an eye on your long-form articles, whatever the subject: from what I have just seen they could be fascinating reads.

vondon302 > BvdV - The Dutch Engineer 02/15/2018 at 09:13

1

Well done! I had zero knowledge about all this. Now I’m wondering how hot it got in those with the motor mounted inside.

I hope the rest of the embiggen posts are this good. My productivity at work is gonna be awful.

Yowen - not necessarily not spaghetti and meatballs > BvdV - The Dutch Engineer 02/15/2018 at 09:55

1

Many stars to you sir! That was a great read. I always enjoy tales of Dutch ingenuity. Maar dat is ook wel begrijpelijk ;)

BvdV - The Dutch Engineer > vondon302 02/15/2018 at 09:56

1

Thanks! The fact that they sometimes ran it without windshield makes me think the answer was: very hot, haha.

I hope so too. Luckily my workday is almost finished!

BvdV - The Dutch Engineer > Yowen - not necessarily not spaghetti and meatballs 02/15/2018 at 09:57

0

Bedankt!

HammerheadFistpunch > BvdV - The Dutch Engineer 02/15/2018 at 10:06

1

Man... That drivetrain. What a wacky solution. It reminds me of the rad4

Sounds amazing and terrible simultaneously terrimazing

BvdV - The Dutch Engineer > HammerheadFistpunch 02/15/2018 at 11:54

1

It’s a propperly wacky solution indeed, but one of the good wacky kind, haha.

Had never seen that one, that is indeed a terrimazing build.

HammerheadFistpunch > BvdV - The Dutch Engineer 02/15/2018 at 11:58

1

I’ve secretly always wanted to do this exact project, but on a 4 door.

BvdV - The Dutch Engineer > HammerheadFistpunch 02/15/2018 at 12:09

0

I fully get why you would want to do that. The mid engine must give you a great weight balance, and the approach and departure angles are huge!

Shift24 > BvdV - The Dutch Engineer 02/15/2018 at 13:21

1

Coming from the US I had no clue DAF had cars let alone a successful Rallycross team. I always see the flat nose DAF truck as the Euro Semi’s. Very interesting and well done article and should be Front page worthy.

BvdV - The Dutch Engineer > Shift24 02/15/2018 at 13:57

1

Thanks! DAF only made cars for a relatively short amount of time (from 1957 to 1976, after Volvo took the car branch), all with the Variomatic CVT transmission. They were never a huge sales success, as they were mocked for being lady’s cars. A move that could have improved sales, and indirectly have saved DAF cars, would have been the introduction of a larger model. Michelotti actually designed a concept for this, however DAF decided against it and sold the design to British Leyland, where it formed the basis for the Triumph Dolomite.

Most of those DAF semis are built about 1 km from my university by the way!

Shift24 > BvdV - The Dutch Engineer 02/15/2018 at 15:56

1

Note to self: Larger model in Europe does not equal Impala or Taurus size.

Lol but still cool stuff and its interesting to see the origins of the CVT and how they had a race version.

shop-teacher > BvdV - The Dutch Engineer 02/16/2018 at 10:47

1

It’s taken me a whole 24 hours to keep coming back and get through all this. I knew nothing of any of this. That is some crazy bonkers stuff!!!!

Thanks for writing about it!

BvdV - The Dutch Engineer > shop-teacher 02/16/2018 at 11:31

0

Haha, glad you took the time to read it!

It’s definitely bonkers, the good kind though!

You’re very welcome! I had a blast researching and writing it.

shop-teacher > BvdV - The Dutch Engineer 02/16/2018 at 11:49

1

Totally worth it!

I just kept the tab open, and went back when I could.

BvdV - The Dutch Engineer > shop-teacher 02/16/2018 at 11:54

0

Haha, good to know you liked it that much to keep it open for a day!

Goggles Pizzano > BvdV - The Dutch Engineer 02/16/2018 at 12:08

1

I don’t know how, but I missed this yesterday. Great stuff!

I’m shocked at the similarities between our embiggen posts. The formatting, writing style, and the subject matter (grass roots rally driver/creative engineering). Cool.

BvdV - The Dutch Engineer > Goggles Pizzano 02/16/2018 at 12:18

0

Thanks! It was one of the first embiggen posts, bumping it to page 4-ish by the end of the day.

Yeah, the similarities are definitely there, haha!

BiTurbo228 - Dr Frankenstein of Spitfires > BvdV - The Dutch Engineer 02/19/2018 at 09:20

1

What an utterly phenomenal little car. Recreating that would be a hell of a cool project :)

It’s a similar thought to an idea I had that I dub a ‘106 T16'. Transverse mid-engined 106, with the standard gearbox acting as a centre differential and regular car diffs at the front and rear. The deal-breaking stumbling block at the moment is that even with the lowest ratio Pug gearbox (3.308 205 GRD) and the lowest ratio front and rear diffs (2.29:1 Ford 7.5") you still end up with a final drive that’s too short to offset with tyre sizes. Even with monster 225/80 16s you top out at 104mph.

This DAF quite neatly gets around that with the CVT :) very smart.

First thing I was thinking is that you could probably stick the engine in the rear, with a shorter driveshaft to there. That way you’d not only get better weight distribution, but you’d also get a rear-biased AWD system using the same principles that result in torque-steer (the shorter of two unequal-length driveshaft transmits more torque).

BvdV - The Dutch Engineer > BiTurbo228 - Dr Frankenstein of Spitfires 02/19/2018 at 10:04

0

It sure would be a cool project! Too bad 55 Coupe shells are relatively rare.

Yeah, it seems very similar to that. Now you mention it, I remember you talking about that idea before, I knew the setup of the DAF seemed familiar :p

That would be a cool way to build a rear-biased AWD system. Makes me wonder if they compensate for the fact that the front shaft is shorter in most AWD cars, otherwise a 50:50 split at the centre diff, would make it front-biased.

BiTurbo228 - Dr Frankenstein of Spitfires > BvdV - The Dutch Engineer 02/19/2018 at 10:20

1

You know I’m not sure whether they’d compensate for that. I’d bet that they measure the output at each end of the centre diff (or rather just build it so that each side of the diff transmits the same torque). Definitely would mean that 50:50 splits would tend towards front bias...

Which DAFs can still be found in reasonable numbers? I must confess I know bugger all about them other than the Variomatic...

Hoccy > BvdV - The Dutch Engineer 02/19/2018 at 10:49

1

He was probably ten years too early with this solution! Though I wonder how it would cope with the turbocharged engines that came in the 80's..

BvdV - The Dutch Engineer > BiTurbo228 - Dr Frankenstein of Spitfires 02/19/2018 at 12:19

0

Yeah, they probably have their ways to compensate for it.

The 66 is still pretty easy to find (last model) , besides that the 2 cylinder 33 is probably most common. But that’s just based on the classifieds, as I’m sure a lot of the ‘rarer’ models are traded between DAF people, without being advertised. So I’m sure there is something around from every generation.

The thing is a lot of them were destroyed in the 80s during the reverse racing, and they preferred the faster 4 cylinder models for that, which are the ones I like most. Combine that with the fact that the 55 Coupe was only made from 1968 to 1972, and you get why they are rare.

I guess using a 66 Coupe shell could be an option, as the major difference is the front, and they are almost the same from the leading edge of the doors back.

BvdV - The Dutch Engineer > Hoccy 02/19/2018 at 12:27

0

Yeah, he was way ahead of his time! The F3 Variomatic was developed to run with only a tiny engine, so that it coped with the BDA was already quite a feat! I’m guessing with the crazy turbo engines this solution would have been hard to implement . Not the CVT as a concept , but the execution I mean, as I don’t think the belts or pullie s would be able to contain that power.

Jonee > BvdV - The Dutch Engineer 02/19/2018 at 14:27

1

Awesome stuff. One of the biggest pleasant surprises of my trip to your country was the visit to the DAF museum. I’ve always been fascinated with DAF and even owned a Daffodil at one point, but I knew almost nothing about the racing heritage of these cars. It’s really incredible what they accomplished.

BvdV - The Dutch Engineer > Jonee 02/19/2018 at 14:32

1

The DAF museum is great, definitely one of my favourites (the fact that it is very close helps, haha). I haven’t been in a while though, should probably go there again soon, haha.

They’ve got plenty of racing heritage, especially in rallying. Sadly racing is what killed tons of  DAFs in the end. It’s so sad to watch those ‘achteruitrijden’ races :(

Jonee > BvdV - The Dutch Engineer 02/19/2018 at 22:59

1

I know, they get destroyed in those backwards races. And there’s so many cars in the race. No wonder they’re hard to find. I got mine from what was probably the only DAF collector in America. They had a couple dealerships here.

KnowsAboutCars > BvdV - The Dutch Engineer 02/24/2018 at 07:09

1

This was nice little read. I love the ingenuity of that drivetrain.

BvdV - The Dutch Engineer > KnowsAboutCars 02/24/2018 at 07:30

0

Thanks!