Around Monaco in first gear.

I remember about 40 years ago reading that the pre-war Auto Unions (or perhaps it was the Mercedes) used to go around the then GP circuit using only first gear. I recently saw another similar statement. How on earth did that work? I know these fearsome brutes had immense power but even so it raises a few questions (at least to me).

 

Presumably at the low speed end they were only doing about 20 mph at the Station and Gasworks hairpins, but must have been over 100 mph around the tunnel or the old quay. That's a ration of ~ 5:1 for the rev range. Some useable rev range!

 

How many gears did they use on the fast circuits? Presumably you would never need more than 2 gears as second gear could then easily accommodate a rev range from, e.g. 70 to 210 mph (which by comparison is only about a 3:1 rev range).

 

If they only used one gear, did they simplify the gearbox design and throw away all the rest of the heavy gearbox components and run the car like a bike on a fix? Was that the gain?

 

If they could get to the end of the straight with plenty of power still coming in, does that mean that they were vastly overpowered at slow speed and could only touch the throttle lightly to avoid burning the tyres up through vicious wheelspin?

 

Any insights would be greatly appreciated.

 

The Auto Union V16 engine was designed to be low-revving, torquey and flexible. Ian Bamsey in 'Auto Union V16 Supercharged: A Technical Appraisal' noted that at some circuits the AUs only needed two gears. As an academic exercise Rosemeyer once did some laps of the 'Ring using only one gear, with revs dropping to 800 rpm at times, but this made it more difficult to drive as the power came in with a bang as the revs rose from this very low level.

I personally don't believe that even the torquey AUs would have used only one gear at Monaco, and am sure that this would have been impossible for the higher-revving, less flexible Mercedes.

This was actually mentioned by a certain Mr Nye in the 90th Anniversary issue of Motor Sport (he did the excellent - of course - section covering the 1930s).  He didn't specify first gear, though, merely saying the V-16 AU drivers lapped Monaco without changing gear, thanks to the enormous mid-range torque. 

Pomeroy, in The Grand Prix Car, gave maximum speeds for each gear for the W125 at Monaco as 60, 93.5, 96 and 122. Karl Ludvigsen, in Quicksilver Century, says that the M125, with suction carburettors as used at Monaco developed 361bhp and 632lb-ft at 3,000rpm. Maximum rpm was 5,800. I think that 361bhp would be more than enough to produce wheelspin at the road speeds found at Monaco. It seems likely to me that the W125 could have lapped Monaco at competitive speeds in a single gear.

In the wet 1936 race, it is likely that most drivers did stay in the same, high, gear.

Edited by Roger Clark, 16 July 2014 - 17:28.

I seem to recall Mr Schumacher finishing second in Spain, 1994, stuck in 5th gear for more than 40 laps, which would indicate quite a spread of power, even with a "peaky" high reving engine?

Edited by f1steveuk, 16 July 2014 - 17:15.

On that occasion Schumacher had no choice. I accept that the Auto Unions, and maybe the Mercs too, could have lapped Monaco using only one gear if necessary, but still think they would have been quicker (and easier to handle) using (at least) two gears. As Spa65 pointed out in the opening post, there were two slow hairpins to negotiate.

In his Monaco Grand Prix history (1964) David Hodges writes:

Six years later [1937] the drivers of the over-powerful German cars used only one gear. ~ The correct axle ratio was of, of course, vital to the German cars . . .

So the story was around that early.

 

I don't think this necessarily means using 1st gear.  I'm sure that racing in 2nd and using 1st for the start would have been considered to be 'using only one gear'

Sounds remarkably like another myth to go with the paint stripping tale.