No life (a.k.a. DattoMaster) 
Joined: 2008/10/10 22:02
From Melbourne Australia (and likely under the car)
Group:
Registered Users
|
it's categorically impossible to produce more cornering Gs drifting than circuit racing (with the caveat of course being that all else being equal, or as much as can be , for the drift vs circuit racer). It's about grip, and drifting isn't. I've been sideways at some ridiculous speeds, but there's a difference between velocity and g-forces, and it should probably start to sink in that traction control on high-end competition race cars is about getting the car out of a corner quicker (and they usually set it somewhere around the realm of max allowable rear wheel speed vs front wheel being 110% or so which isn't the same thing as a loss of grip, after all they are the wheels pushing the car forward and accelerating it). If it was quicker/harder to drift out of a corner sideways at extreme angles, you'd be seeing it happen each and every corner of every racetrack (and for the record, dirt rallying doesn't count, because in that specific scenario, the tyres actually dig in and produce a sort of 'hump' behind the tyres as they accelerate which actually aids grip (and in front when they brake which is why abs actually produces far less impressive braking experiences on gravel) Of course that is just plain physics.
It might _seem_ like the g forces are higher with drifting, or that the car is going faster, but it's just not the case. If it was, there would have to be something very very very seriously wrong with the setup.
I can't re-iterate enough, drifting, by it's very definition, involves a massive _loss_ of grip at the rear, and a lack of grip will not be able to produce anything like the g-forces as a similar corner where the tyres actually do have traction.
It'd otherwise be like saying that the quickest way to run at the drags is to spin the wheels up off the start line and let them keep spinning (without hooking up) for the entire run. Of course, in actual racing, the moment one car lights up the wheels, the driver has to frantically get off the accelerator and roll it back on, as they'll see their competition in the other lane rip away from them. It's really no different save for the fact that one is longitudinal grip, one is lateral.
I don't mean to be a knob about it, but it's pretty elementary stuff and there's no way around it.
I'd go further and make mention of the fact that it's likely the actual on road (or circuit in these cases) distance travelled by a set of tyres is pretty low - before you know it (so to speak) they are worn out. I know I'm being captain obvious. The fact that none have let go _yet_ is not in any way indicative of what can/will happen on a streeter.
the question I was asking about tyre companies wasn't about who sponsors what car per se, I'm asking more along the lines of whether any tyre manufacturers have made tyres specifically for the needs of drifters.
On the question of what is better - lower profile tyres - well if the choice was between 'stretched tyres' (esp to the extent of the first video - I certainly agree with perthute that it's a matter of degree and there's clearly a safe middle ground, and then just the utterly ridiculous.) and low profile, I'd go low profile without any hesitation.
If it was for handling, the options become a little more blurred. It really depends on how hard the springs and shock damping rates are. It's actually possible to get to a point where the suspension is so stiff that the tyre sidewalls are more critical in terms of them actually becoming a part of the suspension (formula one is a good example of this, the tyre sidewall flex is a critical part of it, and if they ran lower profile tyres they'd have to run considerably different suspension/damping specs). There does come a point where a car can be too stiff and so can the tyre sidewalls, and a little 'give' in the sidewall allows for more effective weight transfer and grip.
If the car is street driven, aside from cost, one of the drawbacks of ultra low profile tyres is that they have less safety margin and something on the road (like a brick, or a speed hump if the road speed is high enough) can actually damage the rim. In very very general terms if the roads themselves (whilst free of debris/rubbish) can be bumpy enough that taller sidewalls actually produce a more settled car during more spirited cornering.
It also gets further complicated by the fact that often the sort of tread compound on higher end low profile tyres is 'stickier' than that of more garden variety higher profile tyres of about the same width and diameter (which would therefore mean on smaller diameter rims) so it's not always possible to compare apples to apples. You'd also want to look at overall weight of the wheel/tyre combo - often larger diamter rims and low profile tyres are heavier than smaller rims and higher profile tyres. This makes a difference to the unsprung weight and how the car will behave on rough surfaces (also if it leaves the ground and touches down again). There are exceptions, but usually that's the case. Then you have to look at how far the weight is concentrated from the centre of the wheel/hub - the further out it is, the more 'leverage' it has so it resists changes in speed - i.e. braking and acceleration can both be affected.
unfortunately the more you look into it the more you have to look at and take into consideration. :)
Posted on: 2009/5/14 10:18
|