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Location:
Sydney
Registered:
May 2002
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Countering Understeer....???
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Thu, 26 December 2002 06:17
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Hey all
I would like to know how to counter understeer in a RWD car
Id prefer ppl talking from experience rather than something they've heard
that is all
Thanx Heaps
Mani
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Location:
Cabramatta, NSW
Registered:
May 2002
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 Re: Countering Understeer....???
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Thu, 26 December 2002 13:36
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Depending on how bad the understeer is and the angle of approach. Stepping on the loud pedal can help you tighten the line.
Otherwise, a quick let off of the accelerator should shift the weight to the front and give you more front end grip.
Also lessening the amount of turn on the steering wheel should help. This will make you run wide though and is only really helpful if you're trying to brake at the same time.
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Location:
Sydney
Registered:
May 2002
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Re: Countering Understeer....???
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Thu, 26 December 2002 13:40
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yeah i know of the straightening the wheel technique
but in alot of cases that isnt appropriate
ie: curb !!!
So let off the accelerator ?
wasnt sure about letting off the accelerator cause understeer is such a headf**k
koolies
Ta
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Location:
A.C.T
Registered:
July 2002
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Re: Countering Understeer....???
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Thu, 26 December 2002 22:33
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Yep shutting the throttle is a sure-fire way of transfering weight to the front of the car. If the front has more weight, then obviously the front wheels are pushing down harder on the road, therefore having more front-end grip. However you have to read the understeer appropriately as well, it also depends what caused the skid in the first place. Just shutting the throttle isnt neccessarily going to cure the skid. Infact, depending on the situation, if you just step off it abruptly then it can cause more damage than good, ie. seriouse sudden OVERSTEER! If you are unsure on these sorta things, maybe you should consider a defensive driving course? My dad runs them here in canberra, and they really are helpful. Just a suggestion.
Andre
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Location:
Sydney
Registered:
May 2002
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Re: Countering Understeer....???
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Thu, 26 December 2002 22:44
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oh yeah im definetely gonna be doing a course of some sort once my car is up and running
but i hit understeer every now and then...but its nothing major.....up untill yesterday !!!
im sure u can put 2 and 2 together to why i opened another thread asking where i can fix rim damage
just a lapse in concentration....and realised i was understeering like 2 metres b4 the curb
Ta
Mani
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Location:
Perth - Cannington
Registered:
December 2002
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Re: Countering Understeer....???
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Thu, 26 December 2002 22:56
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simply put.. your understeering will be affected by the speed and weight distribution of your car..
example:
you enter a wide corner that should be taken at 120 for full clearance, while keeping the fastest line, hoewever, you hit it at 150, and when you enter under brakes, you start understeering.
at this point most rookies freak out and fuck their car up on the guardrail.
However, if you know your speed is too high for the corner, rather than clutching to second, stay in neutral, keep braking and get the revs right, you can correct your understeering and pop your clutch one you get it in line again. the entry will look messy , but it keeps your car in one peice, and your exit should be fine.
Take me for example, my tyres burned down during a race, and as i entered into a turn, they didnt respond, so i started to understeer. rather than trying to correct, i sped up, dropped to neutral and used the handbrake to drop my speed, into second, and swung my back end round. the car responded after i had tried to straighten with the handbrake. not sure why it worked, but it did.
I ended up on the worst line for the next corner, but i didnt damage my car, and i made the next corner faily easily because i knew that my tyres were in poor condition. the only other way i know to correct understeer is to pump your accellerator in either way.. usually has the best results.. you only need brakes and gears when you have severely understeered. both pumping your accellerator and braking will throw weight forward to the front wheels, so you should gain more grip.
Your speed will effect your understeer, and your tyre condition, if you know how to keep both in check, you cant miss.
Thats all i can come up with.
[Updated on: Thu, 26 December 2002 22:59]
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Location:
Southern Sydney
Registered:
August 2002
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Re: Countering Understeer....???
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Thu, 26 December 2002 23:23
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Ok firstly I'm not a race car driver nor do I pretend to be one.
I'm a strong believer in prevention rather than a cure so my advice is to simply lower your entry speed into corners.
Break hard before you enter the corner, this will transfer weight to the front of the car and asist in the corner. Breaking mid corner or any other action besides steering will only upset the cars balance
If your in a location where your pushing it hard like this then there shouldn't be any gutters or kerbs..... there should be ripple strips as your on a race track not on the street.
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Location:
Cabramatta, NSW
Registered:
May 2002
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Re: Countering Understeer....???
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Fri, 27 December 2002 01:20
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Sounds like you entered at too fast a speed, turned your steering wheel too quickly, or the camber of the road got to you.
These are just little things that you learn as you drive hard for a while.
Learning to judge the correct entry speed is important.
Being easy on the steering input is perhaps the most important thing you can learn.
And reading the camber of the road will prevent you from experiencing terminal understeer or abrupt snap oversteer.
Oh yeah, as [TOYROTA] mentioned, stepping off the throttle can be dangerous and will only work if your attack angle is right... And you're fast enough to correct the oversteer. Lift off and let the rear out, then ease the throttle back in to get your rear end grip back.
However, if you've got terminal understeer, you're going straight, no sideways momentum, so lifting off will push the weight to the front without the snap oversteer.
I have a sneaking suspicion that this happened on a roundabout...
[Updated on: Fri, 27 December 2002 01:43]
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Location:
Sydney
Registered:
May 2002
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Location:
Southern Sydney
Registered:
August 2002
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Re: Countering Understeer....???
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Fri, 27 December 2002 04:39
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Sorry if you took my advise the wrong way.
But if it was wet shouldn't you have being driving slower?
Anyway... If theres one thing I've learnt over the years I've been on the road its that you don't drive on the limit and always leave room for driver error (yours or others).
No one is perfect, I'd rather make a mistake on a closed circuit. This was all I was trying to say.
Cheers, 
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Toymods Board Member
I supported Toymods
Location:
Turramurra, Sydney.
Registered:
May 2002
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Re: Countering Understeer....???
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Fri, 27 December 2002 06:09
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Uphill actually increases your grip, that's why I love uphill corners. 
One of the scariest things that can happen (& I'm only talking from passenger experience here) is cresting a hill on a corner, when you're fanging. Luckily there aren't too many hill-corners around, but there's a cracker just near my place, which has caused many an insurance claim.
Going up the hill you can corner at a greater speed than normal, but if you don't realize this, as the hill drops away so does your grip. Hello understeer!
It wasn't too long ago a dude wrote off his dads commo, left some great skid marks & wasted one of those black & white <<<< aroow signs. What a thing to see before you stack, a sign telling you you should have turned. 
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Location:
Sydney
Registered:
May 2002
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Location:
Sydney
Registered:
May 2002
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Re: Countering Understeer....???
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Fri, 27 December 2002 06:13
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nah seeing a no stopping sign coming into view as you spin a falcoon with a loaded car trailer at 80-90km/h is funny.. "Buugger that I wish I could stop"
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Toymods Board Member
I supported Toymods
Location:
Turramurra, Sydney.
Registered:
May 2002
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Re: Countering Understeer....???
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Fri, 27 December 2002 07:30
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Well, actually now that I think about it I'm a bit unsure, most of the uphill corners I was thinking of were just ater a flat or a downhill.
It's really the transition of flat to uphill or flat to downhill etc where the car has less or more grip.
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Location:
Cabramatta, NSW
Registered:
May 2002
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Re: Countering Understeer....???
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Fri, 27 December 2002 13:29
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Advanced driving courses are OK for teaching you the basics, but you can't really learn much in the space of the few hours that the courses run for.
All it takes is experience. Track time.
Although it's quite different driving on the track and driving on the street, but at least on the track you can learn car control.
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I supported Toymods
Location:
Northern Beaches
Registered:
May 2002
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Location:
Sydney
Registered:
May 2002
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Re: Countering Understeer....???
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Sat, 28 December 2002 07:37
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Where do ppl recommend for wheel alignments ???
Ive heard Beurepairs are good ???
Ta
Mani
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Location:
Coffs
Registered:
May 2002
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Re: Countering Understeer....???
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Sat, 28 December 2002 13:23
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Does any of this apply to a FWD car understeering in the wet??
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Location:
Sydney
Registered:
June 2002
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Re: Countering Understeer....???
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Sat, 28 December 2002 14:14
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i was pretty surprised but after lowering my car it handled alot better! 
as for a front wheel drive car i found that easing off the throttle mid corner then gradually planting it again helps, but thas just from personal experience. in the wet i havent been able to defeat understeer or aquaplaning (i think) would a rip of the hand brakey work?
theres a place in liverpool off the hume highway that repair rims if you're still interested manipulate. they seem pretty pro about it too
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Location:
Perth - Cannington
Registered:
December 2002
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Re: Countering Understeer....???
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Sat, 28 December 2002 16:39
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Yeah.. pumping your Accellerator will level out an FF type in the wet, as will some very careful braking.. you need to transfer teh weight forwards, seeing as the drive is there already, you also have to make sure you dont over pump it, or you'll be in a game of Spin the car-shaped-bottle, just hope you dont end up having to kiss the rail 
but braking carefully will help, and revving slightly should also.
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Location:
Sydney
Registered:
May 2002
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Re: Countering Understeer....???
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Sun, 29 December 2002 02:27
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Brett
FWD cars use different techniques for correcting understeer as far as i know
Strober thanx mate but i was looking for something closer than liverpool
Ta
Mani
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Location:
A.C.T
Registered:
July 2002
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Re: Countering Understeer....???
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Sun, 29 December 2002 11:18
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There are many varied driving courses around, many of which are perfect for your application. You just need to look around a bit and investigate what each course focuses on. My dad runs stage1, 2, and stage three driving courses, all of which gradually increase in technicality as you progress. Stage three is actually held at wakefield park raceway in Goulbourn. (primarily car control and skid detection, prevention and correction.)
There are almost as many different causes for skids in a front wheel drive car as there are in a rear wheel drive. The ONLY skid that cannot happen in a front wheel drive that can in a rear-wheel drive, is oversteer due to excessive throttle application. Apart from this all the basics are the same, decelerative oversteer, accelerative understeer etc etc... The difference is that in SOME cases, different approaches are taken to correct the skid in FWD as Apposed to RWD. (in some cases applying the throttle in a front-wheel drive helps to counter oversteer)
a good rule to remmember is, whichever pedal caused the skid in the first place, do the opposite to whatever you did to that pedal. I know that sounds weird and confusing but what i'm trying to say is for example, if you accelerated and caused understeer, let your foot off the accelerator. If you accelerated and caused oversteer, back off the accelerator, again. If you braked and cause oversteer, let the brake off, if you braked and caused understeer (locked brakes) get off the brake. etc, you get the picture. Of course, it's not as simple as that. You have to really read the slide and decide HOW much you change the pedal position, and also at what rate. If you are understeering and snap the throttle shut, oversteer is quite possibly going to be the result as before mentioned. You need to do everything in accordance to the exact conditions of the skid, there is no default way to correct a skid. Every skid is different, it's up to you to read it and take the appropriate actions! I hope this has healped somewhat.
André
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Location:
Southern Sydney
Registered:
August 2002
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Re: Countering Understeer....???
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Sun, 29 December 2002 13:14
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That made perfectly good sense....
Thanks.
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Location:
Sydney
Registered:
June 2002
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Re: Countering Understeer....???
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Sun, 29 December 2002 13:25
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no probbies Mani, just posting what i know.
ToyRota, very sound advice, thanx.
does anyone know if double clutching works? is that where you floor it upto 5000RPM and jab the clutch for a sudden 'kick'?
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Location:
Perth - Cannington
Registered:
December 2002
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Re: Countering Understeer....???
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Sun, 29 December 2002 13:29
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that really depends..
Think about it, if you have a car that has understeered with heavy accelleration, you dont want to pop your clutch to 5000rpm, and make your wheels spin..
double clutching is used to increase your speed/type grip, especially drifting.
so as always, it depends on the situation.
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Location:
Cabramatta, NSW
Registered:
May 2002
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 Re: Countering Understeer....???
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Sun, 29 December 2002 13:37
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Err.. Double clutching is only useful if your synchros are gone... It has absolutely no performance benefit.
I think you're just thinking of a clutch dump. I view them the same way that I view hand brakies. They are too violent and upset the car too much.
Some pretty good advice here, but I think you're all ignoring the fact that this accident didn't happen via the pedals, it was just a steering thing... Nothing can save you from that.
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I supported Toymods
Location:
Epping, Sydney
Registered:
May 2002
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Re: Countering Understeer....???
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Mon, 30 December 2002 12:18
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I'm of the general opinion that you should avoid understeer (and any significant oversteer) in the wet. it's quite a lot harder to correct in the wet than in the dry.
I'm a firm believer in what max said.. get to know your car, and practice on nice open roads how to get yourself out of trouble. In my celica (which I knew very well), my soltion to understeer was always 2nd or 3rd gear (depending on speed) and loud pedal to the floor. had just the right amount of power to change understeer into gentle 4 wheel drift, which was perfect for taking corners REALLY fast (as anyone who's cruised with me will testify). However, in my supra that would be a great way to spin out into a tree/guard rail.
If you've entered the corner too fast, my usual tactic is to turn the wheel till it starts to understeer, then use moderate acceleration to encourage some oversteer. it's messy, and if you dont know what you're doing can get you in more trouble than you started, but it gets the car going in the direction you want
bottom line : get to know your car
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Location:
Sydney
Registered:
May 2002
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Re: Countering Understeer....???
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Mon, 30 December 2002 12:32
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Totally agree with get to know your car
Conclusion ive come up with is just experiment with some understeer in the wet.....open wide quiet road obviously...
Ta
Mani
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Location:
Cabramatta, NSW
Registered:
May 2002
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 Re: Countering Understeer....???
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Mon, 30 December 2002 12:57
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| draven wrote on Mon, 30 December 2002 23:18 |
In my celica (which I knew very well), my soltion to understeer was always 2nd or 3rd gear (depending on speed) and loud pedal to the floor. had just the right amount of power to change understeer into gentle 4 wheel drift, which was perfect for taking corners REALLY fast (as anyone who's cruised with me will testify). However, in my supra that would be a great way to spin out into a tree/guard rail.
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In time you'll get used to the extra power and the nonlinear power delivery of the turbo engine.
This is how I drive too. It's just a bit more tricky 'coz if it starts to wheelspin things just get bad really quickly. But you learn to deal with it.
The Supra (with it's extra wheel base) should be more stable for these sorts of maneuvers though. You just have to get used to the car.
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Location:
South Australia
Registered:
July 2002
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Re: Countering Understeer....???
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Mon, 30 December 2002 13:20
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I'm not much of a racer, more a bit of a beginner/weak attempt at a rally-driver, but I'm a bit of a cornering performance fanatic, and not all of this is truly technical (I've yet to go through Race Car Vehicle Dynamics), it may help a little.
Sounds to me like you asked a bit too much of your tyres. Cars will turn in on wet roads to a certain degreee, but it's much lesser because of the fact that the water acts as a cushion between the rubber and the road, on top of that, the friction co-efficient between water and rubber, is pretty darn low. It's basically just what people call aquaplaning.
When a car aquaplanes it's tyres wont get any more rubber back on the surface until either the speed slows down enough that the rate of water dispersion through the tread is enough to allow for contact between the rubber and the road, or the tyres return to an angle that allows for more efficient water dispersion.
Most tyes nowadays have circumferential grooves, and other water dispersion tread pattern catch-phrases. However the theory behind the circumferential grove is simple. Firstly it reduces the contact area of the tyre, which means that the same weight is being applied to a smaller area resulting in greater pressure being exerted on the road/water by the tyre and also - more importantly - it is an easy channel for the water to run through rather than having to disperse the water all the way to the outside of the tyre.
When you turn the wheel, the circumferential groove is then at an angle to the direction the water comes in, which reduces it's efficiency. The other tread patterns are supposed to help out with this, but there's only so much they can do before they let go, and I think you might know what happens then....
The best thing when a car aquaplanes to all hell, or understeers even slightly in the wet (especially if you find yourself just turning more and more and getting nothing), is to actually reduce the amount of turning you are doing, back off and brake whilst you have some decent longitudinal grip, and then turn again.
Booting the car in this circumstance will not make it oversteer, more than likely it'll just reduce your rear-end grip, and make your car slide off the road in a straight line.
My personal preference to all of this is to buy some kick arse tyres, because some moron in a car with 300+ bhp at the wheels will crap his dacks around every corner in the wet and be slow as all hell as opposed to a guy in toyota echo or something gutless with good tyres on it.
I personally use Bridgestone RE711s, but they are kinda cheap in some respects, and too soft for decent longevity. Bridgestone S0-3s or something like that are good I hear. Any top of the range tyre is good. Anything from a reputable manufacturer. Yokohama A008s, Dunlop LeMans 7000 (or some number like that, can't remember), whatever is expensive.
To counter understeer in general, depends on the type of understeer. Terminal understeer like the case above, is best served by trying to get control of the front wheels again. Lifting off the brake if you've locked them up is a good idea, or lessening the amount of steering you are asking the car to do can help so you can back off a bit.
My personal technique is left foot braking, works best on front and four wheel drive cars, although it can be done to an extent on rear wheel drives. (This technique won't save terminal understeer, might make it worse, or if you are really sensitive, might help a tiny fraction).
When keeping your foot on the accelerator, pull your left foot over and brake a little. Or even lift off the accelerator at the same time if you get better at feeling when the tyres are on their limit. This is a weight distribution trick, but on wet/slippery surfaces you can use it to partially lock up wheels as well. In a front wheel drive you can use it to partially lock the rears to send the rear end around a bit (don't fully lock them though, that'll slow your corner right down as you wrestle the car back), same with four wheel drive. In rear wheel drive you mostly do it to play with the weight, but you can "drift" the car in with left foot or "trail" braking (possibly even with your right foot).
This may not seem related, but watch Valentino Rossi on a MotoGP bike when he goes into a corner, he's using the resistance to rotation from the engine to make the rear end kick out a little into a corner, same thing with rear wheel drive, adding a little bit of resistance can make the tyres just step over their limit a little bit without locking, just enough to drift the rear end out and get some good turn-in.
Although, none of these techniques are at all useful without practise.
It may seem crazy, but the best place to practise is on a dirt road. Not quite as crazily deadly as a soaking wet tarmac road, but it'll let you feel out the limit of the tyres but also what the tyres and the car does when they are on the limit. It's also alot slower, everything on a dirt roads happens slowly. Getting sideways on tarmac requires an incredible amount of speed to break the traction you have on that surface (unless you are being a bit of a show-pony), whereas dirt you can get sideways going 30km/h.
Also you can practise recovering from the many brake lock-ups you'll encounter with your first forays into driving on dirt. The only problem is the trees along the sides of the road. A good idea is to try to oversteer through the corners, that way if you do stuff it up, you'll probably just spin to a halt in the middle of the road. If you understeer, you're screwed
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I supported Toymods
Location:
Epping, Sydney
Registered:
May 2002
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Re: Countering Understeer....???
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Mon, 30 December 2002 18:43
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I know it's a matter of practice... until then it's corner like a grandma though.
what I really need is a few track days.
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Location:
Cabramatta, NSW
Registered:
May 2002
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Re: Countering Understeer....???
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Mon, 30 December 2002 22:20
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Yeah, I was terrified of my car for months when I first got it back after the engine conversion...
All it takes is time. But you learn respect for a powerful car. I could never do some of the things I used to do, now that my car has so much more powerful. It's just too scary.
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Location:
1st street on the right
Registered:
November 2002
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Re: Countering Understeer....???
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Tue, 31 December 2002 06:43
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No one has yet mentioned setting up your car correctly. Spring rates, damper rates, sway bar stiffness, camber/castor/toein-out all affect how your car will steer. I know there isn't much scope for adjustment on most cars but the basics of the first three I mentioned are most changeable. Too stiff in the front (apart from being embarrasing) will cause understeer but so can too soft. This can also affect the rear and vice versa. Find some text (or better someone with experience) who has set up race cars, esp open wheelers for advice.
And going to adv driving courses is great advice. Also try something like driving a formula ford for a day. There is something driven on perpetual oversteer/drift.
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Location:
South Australia
Registered:
July 2002
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Re: Countering Understeer....???
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Tue, 31 December 2002 16:52
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Unfortunately altering the setup of your car is generally not as cheap as altering your driving (unless you make a mistake in attempting to do so).
On top of that, there is no real way to reduce understeer throughout the corner. Most (damper) setups are a compromise as to whether you want neutral/understeer into a corner, or neutral/understeer out. Most spring set ups are fairly limited, because you generally have to match the rears to the fronts and you'd only change the overall stiffness of the car, sway bars are more tricky.
Anyway, I'm not a specialist. 
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Location:
Sydney
Registered:
May 2002
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Re: Countering Understeer....???
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Tue, 31 December 2002 20:30
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Thanx heaps ppl for all the tech responses.....very informative
Very helpful.....its good to know these things
TA
MANI
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Location:
nth ringwood, Victoria
Registered:
August 2002
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Re: Countering Understeer....???
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Wed, 01 January 2003 02:20
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gee mani did you fuck 1 of my nice mags already ,best of luck to get it fixed ,also dont race with that mag any more it wont be as strong now ,and could let go under cornering
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Location:
Sydney
Registered:
May 2002
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Re: Countering Understeer....???
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Wed, 01 January 2003 09:29
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No glenn the rim is not .... gone.....as u suggested
it doesnt need to be trued
just damage to it cosmectically
deep scratch u would call it.....very deep
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spin spin spin hehe