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View Full Version : Is it possible to have too much tire grip?



SIMPLETON
08-01-2004, 04:22 PM
We always here "the more grip the better". But can more always better? Can more be bad? Most cars on the market dont have enough torque to ever have too much grip, but for some high-performance cars with gobs of acceleration could reach the limits of tire technology. What I'm really asking is if it had... lets say 600hp and tires that you might find on an F1 car and the driver floored it would it be possible to break driveline components? Even F1 cars that have traction control dont run on maximum traction. They run somewhere at around 12% tire slippage and theres got to be a reason for that

Matra et Alpine
08-01-2004, 04:46 PM
We always here "the more grip the better". But can more always better? Can more be bad? Most cars on the market dont have enough torque to ever have too much grip, but for some high-performance cars with gobs of acceleration could reach the limits of tire technology. What I'm really asking is if it had... lets say 600hp and tires that you might find on an F1 car and the driver floored it would it be possible to break driveline components? Even F1 cars that have traction control dont run on maximum traction. They run somewhere at around 12% tire slippage and theres got to be a reason for that
Yep non-slip tyres would have huge shock-loading on the drivetrain that would be prohibitively heavy and expensive to supply - think of an Abrahms gearbox :)

Also, you're only thinking straight line. it is more critical for lateral slip to be present and preferably controlled and gradual. Otherwise you get a car which grips in cornering and then snaps loose. You want a car where you can feel the onset of slip before total grip is lost. Then you can control the car through the corner.

johnnynumfiv
08-01-2004, 05:14 PM
The one of the major downfalls of the Mg midget is that the rear axles can break. If you you floor it, the axle can get over torqued and break, then the the wheel just falls out. If there is to much grip, wont it just rob hp?

Matra et Alpine
08-01-2004, 05:30 PM
The one of the major downfalls of the Mg midget is that the rear axles can break. If you you floor it, the axle can get over torqued and break, then the the wheel just falls out. If there is to much grip, wont it just rob hp?
Depends :)

Rolling resistence robs HP.
The losses in the deformation of the tyre wall and the spread of the footprint can all soak up power.
But it's small for a properly inflated tyre.
Too wide a tyre can 'lose' power in the required slip to make the inner and outer edges of the tyre go round a corner.

KnifeEdge_2K1
08-01-2004, 07:49 PM
anyone know what the wrc cars use on tarmac stages? gravel stages? (the ice/snow ones dont really matter since they get one's with spikes :D)

i heard the regulation maximum was 225 width and i thought that's kinda low

i'd expect the larger cars (impreza and lancer) to use something in the range of 245s on the tarmac stages

can anyone clear this up?

crisis
08-01-2004, 11:30 PM
The transmission will generally give some. A clutch will slip or a torque converter. F1 have restrictions on tyre size to reduce grip but if they were given open slather I rekon they could organise some farely sticky rubber.

Matra et Alpine
08-02-2004, 03:31 AM
The transmission will generally give some. A clutch will slip or a torque converter.
Beyond the controlled slip then a clutch would be sized to match the power.
In competition they are scaled for NO slip.
Makes for a fast bite and the reason why stalls are easy :(

Torque convertor - I'm saying nothing:)

GTR Dreamer
08-02-2004, 11:46 PM
i have also heard you can brake axels and stuff with too grippy tyres. it makes sense though, its like driving with the handbrake on :D , but thats a bit differnt i guess, any how, do you get where im comming from. :confused: :rolleyes: :D

KnifeEdge_2K1
08-03-2004, 07:37 AM
i have also heard you can brake axels and stuff with too grippy tyres. it makes sense though, its like driving with the handbrake on :D , but thats a bit differnt i guess, any how, do you get where im comming from. :confused: :rolleyes: :D

i doubt the tyres will have enuff grip to overcome the structural stability of an axel ... unless of course its made if tin or something

usually when a manufacturer decides to put lotsa power in they strengthen the chassis drivetrain engine internals suspension, everything but i guess custom aftermarket jobs are where a bunch of young rich kids with the common sense of a watermelon decide to add nos and superchargers/turbos to their lil civics or m3s

Matra et Alpine
08-03-2004, 08:10 AM
i doubt the tyres will have enuff grip to overcome the structural stability of an axel ... unless of course its made if tin or something
In the case of the MG, it was designed in the late 50s so not really up for the job of current engine tuning of the original block :) Historic racing means you have to use the components availabel then.

BUT, even in the height of the Escort RS1800s it was feasible to snap a rear half-shaft. All club racers and rally teams woudl use Ford Transit rear axles ( teh ATLAS ) to get enough metal in to handle the torque !!

Again in rallying there are more force changes than in typical racing.
So when a car launches you BETTER be a good enough driver to match wheel speed to ground speed for the landing or 1 of 2 things happend ( and often both ) you got thrown off track with the deceleration, you break a drive shaft.
Also, with very grippy tyres if a wheel hits loses grip, spins up and THEN bites the tyre CAN createenough grip to effectily have ALL the power of the engine driving the ONE wheel at the time and - again - wil easily break a half/drive shaft. This is happening hundreds of times in every minute of every stage !!!!

usually when a manufacturer decides to put lotsa power in they strengthen the chassis drivetrain engine internals suspension, everything but i guess custom aftermarket jobs are where a bunch of young rich kids with the common sense of a watermelon decide to add nos and superchargers/turbos to their lil civics or m3s[/QUOTE]

GTR Dreamer
08-04-2004, 12:11 AM
i doubt the tyres will have enuff grip to overcome the structural stability of an axel ... unless of course its made if tin or something

usually when a manufacturer decides to put lotsa power in they strengthen the chassis drivetrain engine internals suspension, everything but i guess custom aftermarket jobs are where a bunch of young rich kids with the common sense of a watermelon decide to add nos and superchargers/turbos to their lil civics or m3s

yer well i read it in a magazine, someone was talking about some kind of tyres and said they had broken some nine inch axles with them. :rolleyes:

johnnynumfiv
08-04-2004, 07:41 AM
yer well i read it in a magazine, someone was talking about some kind of tyres and said they had broken some nine inch axles with them. :rolleyes:

Thats a little unbelieveable, since the ford 9 inch axle is pretty much bullet proof, and they are used in drag racing because they don't break.

GTR Dreamer
08-04-2004, 11:35 PM
yep well here is the sort of tyre they were talking about.........Mickey ET Street Tyres.....>??????????????dont blame me if im wrong