Traction in a MCS

[seight]

Hi!
I am in the process of checking out my potential next car.
I went to the Mini dealer and got a test drive.
Unfortunately they could only supply me with a Cooper (not an S).
I must say I was quite impressed by how much fun you could have with so little power.


But one thing became quite apparent, traction(or rather the lack of it at times).
I had no trouble getting the traction control to wake up, when enjoying spirited
driving on some rather nice and twisty road.
I assume that this is mostly down to this car being fwd, now if I could do this so easily
with a puny 115bhp, how will the same car cope with 200bhp? Will the traction control just make the extra power useless when pulling hard out of corners?
Will the new LSD be sufficent to help things out?
It would be such a waste to spend so much more money on extra oomph, if it is
either lost in wheelspin or being killed by the tractioncontrol

[obehave]

LSD will help. So will throttle control.
The S is a bit heavier as well

[seight]

So you recon the extra weight will increase the traction? It will give poorer power to weight ratio (compared to no weight increase), but I guess that is no good if the extra power only ends up in wheelspin.
Has anybody else found other tweaks than adding an LSD to improve traction?
Adding huge tyres is not necessarily a good thing as it increases the unsprung weight of the car(as well as the rotational weight). Throttle control is probably a good thing , but I would rather have a car in which I could keep my foot down rather than having to slow down all the time Isn`t one of the Minis strong point that It can maintain good speed through corners?

[Wobert]

Quote: Originally Posted by seight

So you recon the extra weight will increase the traction? It will give poorer power to weight ratio (compared to no weight increase), but I guess that is no good if the extra power only ends up in wheelspin.
Has anybody else found other tweaks than adding an LSD to improve traction?
Adding huge tyres is not necessarily a good thing as it increases the unsprung weight of the car(as well as the rotational weight). Throttle control is probably a good thing , but I would rather have a car in which I could keep my foot down rather than having to slow down all the time Isn`t one of the Minis strong point that It can maintain good speed through corners?

The force at the wheels is directly affected by the weight of thecar "pushing" the tyres onto the ground.......if you increase the weight, the tractive effort increases.....

[Mugami]

Not going to put up much of an argument on what wobert said for in a way he is correct but in many others he is not. Being a FWD car Hard excelleration has always been the downfall for this configuration. Since the Wieght transfer during it. take wieght away from the front end causing the wheel spin. The MCS with the SS+ package has a better spring set than the MC but will still have wheel spin. LSD have better traction than the open diff but isnt a cure for it. Taking a page from Drag FWD cars .. that put wheelie bars on the back of them not to prevent the cars from doing wheelies but to keep the wieght tranfer from happening to prevent wheel spin. But thats not ideal for street use. For the Road racer better spring packages, sway bars, shocks, etc improve the handling but they still need throttle control for the wheel spin. Just not as much as with the stock set ups.

Hope this helps and you dont mind my rattling..

Have fun, Be safe and Keep MOTOV8N

[Wobert]

Quote: Originally Posted by Mugami

Not going to put up much of an argument on what wobert said for in a way he is correct but in many others he is not. Being a FWD car Hard excelleration has always been the downfall for this configuration. Since the Wieght transfer during it. take wieght away from the front end causing the wheel spin. The MCS with the SS+ package has a better spring set than the MC but will still have wheel spin. LSD have better traction than the open diff but isnt a cure for it. Taking a page from Drag FWD cars .. that put wheelie bars on the back of them not to prevent the cars from doing wheelies but to keep the wieght tranfer from happening to prevent wheel spin. But thats not ideal for street use. For the Road racer better spring packages, sway bars, shocks, etc improve the handling but they still need throttle control for the wheel spin. Just not as much as with the stock set ups.

Hope this helps and you dont mind my rattling..

Have fun, Be safe and Keep MOTOV8N

I was going to add that the effects of weight transfer during accelraton will negate the effects of the weight increase somewhat.

In some ways increasing the value for mu (the co-efficient of friction between the road & tyre) is going to give more effect than the weight increase......and other than lowering the gearing or reducing the rolling radius of the tyre, there ain't much else you can do to improve the traction.

[Paul]

Better tyres than the runflats will help quite a lot too, they're generally not too grippy, and have very little "give" in them, because of the stiff sidewalls they're more a case of grip, or no grip.

[seight]

Now we are getting somewhere, all relatively unsuprising stuff. Sticky tyres, stiffer suspention(in particular stiffer at the rear perhaps,
to provide some sort of "anti squat" effect).
The SS+ package, it that the lowered suspention setup that is offered by the factory?
(is it stiffer for the MCS than for the MC?)
The reason I am so worried about traction is that I am currently driving a Toyota Celica gt4(turbo 4wd), where loss of traction is not really a big issue
I would preferably have wanted a rwd(or awd) car, but the Mini does have a certain attraction which may convince me to suppress the need for rwd, at least if I know I can get sufficient traction. Now I just need to find a MCS to test drive as I need to figure out if the weight makes the difference.
Another thing, how is the responsiveness of the MCS engine compared to the MC? The MC I tried seemed to scream for a somewhat lighter flywheel, as it was a bit slow to respond when I blipped the throttle.

[SteveM3]

You didn't say what experience of other cars you have. The Mini has good traction for
a FWD car. It may be a case of you getting used to FWD, but if not you'll have a problem
with the ASC. It doesn't cut in too early unlike some rival systems but it does cut the power
almost completely when it operates. I don't like it at all when it operates but have been
pleasantly surprised how rare it occurs. Factors like better (e.g. non-runflat) tyres help but
you'll not make a significant difference. Although good for a FWD car the traction will never
compare with a good RWD car e.g. anything with BMW's z-axle. If you are an experienced
FWD driver and you were reaching the traction limit several times in a Cooper then you may
be better off looking at something like a Scooby .

[05HB]

Has anyone tried having their tires siped to improve the grip? It's supposed to improve traction, especially on wet or icy roads. Not sure how much it helps on dry pavement. Also not sure if that's a recomended procedure for run-flats.

[obehave]

Quote: Originally Posted by 05HB

Has anyone tried having their tires siped to improve the grip? It's supposed to improve traction, especially on wet or icy roads. Not sure how much it helps on dry pavement. Also not sure if that's a recomended procedure for run-flats.

Cutting extra sipes in a street tire is a bit much.
Or just buy a good track tire.

[justbob]

Yep, wheelspin is a classic problem in FWD cars under initial acceleration, due to the fundamental physics of the situation. The MINI handles this quite well, I think, compared to all of the other FWD cars I've owned. The new LSD should help with this, but driving technique is the real key.

I have to admit that I've always been an advocate of FWD, mainly because I'm more interested in maintaining speed while moving under all conditions than in mere acceleration from a standing start. If I was interested in that, I'd just buy a RWD car with the biggest engine possible, strip out all of the seats and accesories, and drive red light to red light, stopping every 15 minutes or so to fill up my gas tank.

Keep in mind that the MINI is designed to be driven, not dragged.

[seight]

Being able to maintain speed is a good thing, but occasionaly you have to slow down a bit before corners because of poor visibility It would be very nice indeed if the car could cope with situation when the driver wants to floor the throttle when the coast is clear(when exiting the corner)

Talking of handling, I noticed that the MC understeered slightly (not suprising since it is a fwd car). How easy is it to make the car even more neutral? How much worse is understeer in the MCS?(noticable?)

[obehave]

Quote: Originally Posted by seight

Being able to maintain speed is a good thing, but occasionaly you have to slow down a bit before corners because of poor visibility It would be very nice indeed if the car could cope with situation when the driver wants to floor the throttle when the coast is clear(when exiting the corner)

Talking of handling, I noticed that the MC understeered slightly (not suprising since it is a fwd car). How easy is it to make the car even more neutral? How much worse is understeer in the MCS?(noticable?)

Understeer is pretty consistent in both cars.
The easy route is a stiffer swaybar in the rear. I've done this. On the street and even moderate auto-x this works pretty well. Real track racing is another matter.
The real answer is to tune the suspension as a whole and do it properly. Just a bit more expensive

[seight]

I don't really need to set the car up for the track, as I have got something rather quicker for that But what sort of tuning are we talking about here(for the track)? adjustable shocks(both height and bound/rebound),different springs, bushes, and antirollbar?
Doesn't some of the Mini aftermarket suppliers offer such kits for a sum of money which
is not silly?