Chassis - F1 vs Road

[H701]

Evening all (happy new year too)

I've been in a little debate of which you may take interest

Someone was using a photo of an F1 car of old with "stretched tyres" to point across a point that stretched tyres are better to use than traditionally mounted tyres on a road car. My response was simply you cannot compare an F1 chassis to that of a road car which hasn't been agreed with fully, only a partial agreement saying they're not the same but are not world's apart.

my view is that the Chassis of an F1 car is entirely different animal to that of a Road car, the design criteria before anytthing else would've been vastly difference. My mind promptly crashed at this point that it was seen they're the same?

What are your views on the differences of F1 chassis' vs Road Cars from a design perspective
Also the affects of a stretched tyre on an F1 car as opposed to a road car (if you dare venture into that area)

Your time is much appreciated

Andy

[godlameroso]

The perfect mount for road cars is precisely with the tire sidewall stretched just a few mm. It keeps the contact patch from squirming outside of the wheel.

Much like perfect camber will maximize the contact patch in a corner, the perfect sidewall stretch will keep the contact patch under the wheel.

[Greg Locock]

I recently measured a vehicle with 1/2" difference in rim widths. In the linear range the difference between them was less than test to test variability. I do have some old papers from one of the tire manufacturers which show trends, but if you were to add tire pressure as an additional variable you might decide that higher tire pressure plus narrower rims was a BETTER solution for a given car.

There are no rigid rules for black round things except that Michelin know what they are doing about 5 years ahead of the best of the rest. Shields up.

[godlameroso]

There are no rigid rules for black round things except that Michelin know what they are doing about 5 years ahead of the best of the rest. Shields up.

/thread.

[Greg Locock]

Is that a new version of Godwin's law?

[H701]

So with that information in mind.

What makes an F1 chassis fundamentally different to that of a road car?
Where the tyre use is concerned (I appreciate that a chassis sole purpose us to utilise it's tyres but it's a very broad point)
Why couldn't I put the large F1 tyres straight on a Micra/MX5? Or of similar dimensions where translatable and expect the same result?

The debate suggests that because both cars are subject to the same physics they are the same.. its my understanding that tyres don't wholly apply to physics as they're elastic and don't follow a given rule.
We're all subject to the same physics and argued it was an irrelevant point to dismiss the difference in these two chassis'

[Just_a_fan]

The old F1 tyres were cross-ply. Road car tyres are almost exclusively radial these days so there is no comparison other than looks. As for stretching tyres, it looks ridiculous and is likely to be illegal (at least in the UK and similar jurisdictions).

[Just_a_fan]

What makes an F1 chassis fundamentally different to that of a road car?

For a start, F1 cars have very limited suspension movement and make use of tyre sidewall deflection to a large degree. Road cars have large suspension movement and relatively very little sidewall deflection.

Why couldn't I put the large F1 tyres straight on a Micra/MX5? Or of similar dimensions where translatable and expect the same result?

Suspension design. Oh, and F1 tyres are designed to work at a temperature you'd struggle to achieve/maintain on the road. The tyres just wouldn't "work".

The debate suggests that because both cars are subject to the same physics they are the same.. its my understanding that tyres don't wholly apply to physics as they're elastic and don't follow a given rule.
We're all subject to the same physics and argued it was an irrelevant point to dismiss the difference in these two chassis'

Two different road car tyres will give different results on a given road car. Why would a tyre designed for a totally different environment give the same result when fitted to that road car?

Your friend has an amazingly simplistic view of the world.

[H701]

Exactly my thinking.
Simplistic view would be the kind description.
The chassis' in a general sense are completely different to those who understand it. You've only to compare roll centre for example of the two to see such a vast difference

The new found view is that a chassis' fundamentals is to work with the tyre to achieve 'grip'. With that generalist view a downhill gravity buggy is the same as an F1 chassis. True also of a pushbike.

Appreciate all of the inputs. The debate has turned, in my eyes, to be such a broad meaning of "chassis fundamentals" that both chassis are categorised together to coinside with their view