1930-31 Mercedes SSKL

[berfinroy]

These pure race cars differed from the so-called "street" SSK cars in that the frams and other components were drilled out to further lighten the cars.None survive today, but contemporaty photos show various degrees of chassis drilling. Rudi Caracciola's winning 1931 Millie Meglia car is drilled only up to the cochpit and in the front of the engine cradle. Others were drilled from the rear up to the firewall, and at least one was drilled all the way from front to back, although one photo seems to show that the holes from the firewall foreward were subsequently filled in suggesting that the engineers concluded after the fact that they had sacrificed too much rigidity with that degree og drilling.

I know this is pretty esoteric stuff, but I'm wondering if anyone shed any historical light on these variations.

[t walgamuth]

I have no facts but my observations about and participation in racing activities would suggest that they kept wanting to go faster by making it lighter, so kept drilling holes until something cracked. I know on my old Formula Ford that whenever I took off something that looked just fine it would often come off in three pieces which had been held together by the bolt and washer.

They were fast cars in their day. The supercharger was connected though a clutch which could be activated by the driver by pushing the pedal down further, like a progressive linkage in a multiple carb setup. They were only allowed a certain number of seconds, like perhaps 15 of boost at one time. So it was sort of a passing button using 30s tech.

Pretty nice to look at too.

[Mxfrank]

In 1928, Bentley had a problem with drilled frames at Le Mans. At least one of their cars had to retire with a broken rail. I would guess they were balancing lightness with durability, and hedged their bets by using different patterns. Bentley whupped the SSK's at Le Mans in 1930. The Bentley's had continuous supercharging and forced the Mercedes to blow out their headgaskets by using too much boost.

[Idle]

Ford lightened their race cars during the 60's by acid dipping the body parts. They destroyed a lot of doors and fenders in the process since they were trying to get them paper thin.

The rules then outlawed the drilling of random holes. The rules also stated that production body parts had to be used.

So they started with production parts and then 'treated' them (with acid) 'to race car standards'!

It was in intensive process since the body parts on the outside had to look normal. So a lot of sanding was needed to take out the ripples.

The roll cage, which was required and had to be of a determined strength, held the cars together. There was no way to cheat on the construction of the roll cage.

But I bet someone found a way to do just that.

[t walgamuth]

You can bet they cheated on roll cages too!