5 replies to this topic

[bradbury west]

Firstly, I am not an engineer, so I expect to be met with hoots of derision for this, but it is something which has intrigued me for a while.

The Bugatti T251 is usually regarded as something of a failure, qv its one race appearance.

However, looking in the files for something else, I came across a DCN article on the T251 (and the T32 tank).

Ignoring the other innovations which the T251 had,
design of the engine
transverse engine (I know about Cisitalia),
gearbox with Porsche syncro, and diff., integral with the crankcase - it would be 8 years before Honda and Maserati came up with the similar, but V12/combined gearbox set up.
hollow, centrifugally cooled discs with twin calipers
coolant running through chassis tubes.
perhaps unwittingly advanced body shape.

it is the original suspension which intrigues me. Doug's article features a small Ludvigsen photo of the rear suspension, which was replicated at the front.

Apart from the de Dion tube and twin radius rods, this featured " at each hub a vertical pushrod to operate bell-crank spring-actuators which pivoted on bearings high on the chassis, their projecting inboard ends then compressing long push-rods reacting against steeply angled coil spring/damper units anchored low on the opposite side of the frame, where several chassis tubes converge. This arrangement gave a kind of "X" shaped spring and pushrod formation criss-crossing the frame"

Presumably this would aim/help to optimise wheel verticality vs body roll? It might also have helped to produce the good traction, coupled with mid engine etc., perhaps also a more stable braking situation at the front.

The photo makes this clear. Perhaps Karl Ludvigsen could put the photo up.

Later at the factory, when no longer involved in racing, this setup was modified/re engineered quite brutally in aesthetic terms with massive spring mounts and new vertical coil/springs, and not subsequently used, which is the car I have seen previously at Schlumpf, and not how the car was in its one race.

See page 29 on this link from Jaap Horst , scroll well down the page, almost to the bottom, to the T251 images at Schlumpf. The whole site is super for Bugattistes.

http://www.forum-aut...t189904-980.htm

In a column last year in C&SC Mick Walsh mentioned that he had been reliably informed that Colombo's original plans featured independent front suspension, (perhaps this type of design), but Roland Bugatti decreed a rigid axle, the rift over the design compromise leading to Gioacchino Colombo leaving Bugatti. So perhaps his design would have been quite radical.

However, thanks to Marc Fenijn I have read notes on Norbert Hamy's Trebron system, and the design by Rick Parsons, both aiming to achieve the same as a de Dion keeping the wheels vertical and parallel in all conditions, as well as the Fuller suspension system , and I am aware of Jim Hall's articulated de Dion on the 2H, not that I understand any of it for a moment.

I have also come across , on the Technical Forum, something on Renault/Michelin's OPT system, a French acronym for Optimum Contact Patch, "a mechanical suspension device...........using a complex linkage that keeps the wheel upright even when the car is tilted in a corner", thereby optimising traction capability.

Ignoring whether any of the systems work as intended, certainly with/out compromises or complications, is this what Colombo was really aiming for, and was he ahead of his time, albeit certainly in the wrong place, and at the wrong time? Ignore the 251's poor one race performance since lack of funds precluded testing etc.(shades of Gordini?)

Mick Walsh notes that the Bugatti Owners' Club magazine ran a special supplement on the car with scoop pictures. Perhaps if we saw the original drawings/pictures it might show us just what Colombo had in mind.

Interestingly MW tells of the replica 251 being built " to factory drawings" but in the photo that car features the 2nd phase dampers, not the "X" linked bell-crank set up in the photo of the race car.

Any answers please, other than the inevitable hoots of NO to the third paragraph from the end?



Roger Lund

[macoran]

Originally posted by bradbury west


it is the original suspension which intrigues me. Doug's article features a small Ludvigsen photo of the rear suspension, which was replicated at the front

Roger Lund

Roger are you speaking of the Doug Nye article in Motorsport October 1997 ?

[ian senior]

I don't think any hoots of derision are in order. It's something I've puzzled over too and it's an entirely reasonable question.

I'm no engineer either, but was it a case of applying solutions that were good in theory but with insufficient understanding of how to deal with them, and develop them, when the car finally hit the track? Or was it simply too much new stuff in one car? You're asking for problems if a car is new from the ground up and almost everything on it is innovative - and, seemingly compromised too in respect of what Colombo wanted to do and what he was allowed to do .

Given time and sufficient money, perhaps it could have been made to work. Were they too hasty in calling a halt to the project?

[sandy]

[QUOTE]Originally posted by bradbury west
[The Bugatti T251 is usually regarded as something of a failure, qv its one race appearance.

See page 29 on this link from Jaap Horst , scroll well down the page, almost to the bottom, to the T251 images at Schlumpf. The whole site is super for Bugattistes.

http://www.forum-aut...t189904-980.htm

This is a most interesting topic. If the rear engined T251 Bugatti and perhaps a successful follow on of the rear engined Sacha-Gordine had come good (and with a revised and more competitive 8 cyl Gordini) perhaps we could have seen French domination of F1 in the late fifties.

[Vitesse2]

[QUOTE]Originally posted by sandy
[QUOTE]This is a most interesting topic. If the rear engined T251 Bugatti and perhaps a successful follow on of the rear engined Sacha-Gordine had come good (and with a revised and more competitive 8 cyl Gordini) perhaps we could have seen French domination of F1 in the late fifties. [/QUOTE]
Well, up to a point. But French pride would have demanded French drivers. And there was ..... er ..... um ..... Jean Behra and ..... er ........ :

[macoran]

Maurice Trintignant ...........???