SDB

IMPORTANT!!...

THERE ARE NO HARD AND FAST RULES THAT WILL SAVE YOU IN A BEND.

Throttle is not always the answer, lifting off is sometimes the answer, brakes are sometimes good, sometimes bad.

The basic deal is (in normal circumstances).. lifting off will shift the balance towards oversteer, and applying throttle will shift the balance towards understeer until you reach the amount of throttle to spin some or all of the wheels. At this point all sorts of cool things can happen

As mentioned above, entry speed is the first important thing.. go into a bend fast enough and there is no ammount of throttle or brakes that will get you round.

What happened in this circumstance? Difficult to say.. but..

The basic facts are that the front end lost grip when you lifted off.

This does not mean that the lift-off *caused* the understeer. I would suggest two possible causes..

1) Slippy road surface. There could have been frost / deisel, etc on the road. Mix

2) Release Agent still on the tyres. If they are less than 500 miles old, there is a good chance they still have residue from the release agent on them which means they can be VERY slippy indeed.

Don't think about modding your car to cope with situations like that as they are uncommon, and require the correct control inputs from the driver to sort out. If you mod your car to cope with them.. it just means that the next time it catches you out, you'll be at a higher speed!

I would advice getting some advanced limit handling driver training.

All the best

Simon

[Edited by Simon de Banke - 12/9/2001 11:29:39 PM]

sulli

Edit - double post

[Edited by sulli - 12/11/2001 6:52:07 PM]

ScoobyDan

Hi All,

Please excuse me if this is the wrong forum, as I'm not sure of the best place to post this...

Coming home from last week's Southern area meet, I found a nice roundabout to 'test' the Scoobie's grip. The roundabout is quite small, with only three exits, with the 'straight ahead' exit being at about 45 degrees beyond straight ahead (i.e. slightly to the right). Does that make any sense?

Anyway, I was approaching this roundabout, there was no-one else on the road, so I dropped to 3rd gear, built the revs up, then let rip round the roundabout. As I entered the roundabout, I realised I was going too quickly so I lifted off the power, expecting the backend of the car to drop in line with the front to get me round. Nothing happened! Instead, I carried on in a (almost) straight line, with the front wheels apparently having no control of the direction of the car! I stamped on the brakes, and (luckly) caught control again inches away from the kerb.

I have some brand new (less than 500 miles) Falken tyres all round (brought with the Team Dynamics 17" wheels from TSL), so I don't think it was loss of grip. The road was not wet, but it is concrete - which I know is not as grippy as 'normal' road surfaces.

My question is - how do I stop this from happening again? Is this what the (in)famous 'bump-steer' mod is for? Would a strut brace help?

Any advice gratefully received. Thanks.

Daniel
MY93 WRX

PS Sorry about the essay!

Steve Terzo

I've just put an OMP strut brace on mine, having fitted them to my previous cars. I've found that it greatly improved the scoobys turn in, but it's more likely to break into "understeer" on the limit, rather than slip out progressively. IMO though an overall improvement to the cars handling for only £40!

MichelleWRX1994

I now have lovely majority oversteer without the bump steer mod (which does help - is £100 approx from Powerstation)

I just have very stiff suspension and that suffices to give me overall good handling that sways mainly to oversteer.

I think it depends on how tightly you were going round and how quickly you came off the gas.........if you have no mods - don't forget the Imprezas natural tendency is understeer.

Robertio

iTrader: (1)

Obvious answer:

Enter the roundabout more slowly

May be that your tyres have not bedded in yet, and still have the infamous new coating on them.
Bumpsteer mod and / or geometry setup should help matters, but you have to be confident you can live with lift off oversteer, frosty / wet mornings often lead to people finding out that this may not be a good thing on muddy country roads.

monkeytennis

Dan - Got to agree with you. Have to say that given the Scooby's reputation for handling I was a bit disapointed with the feel from mine especially once the front end lets go & understeers. I much preffer lift off oversteer, but its so hard to provoke it.

Any suggestions to improve front end grip would be most welcomed...

Bob Rawle

Your big mistake was to lift off, you need to get your entry sped correct and then apply power as you go round, this will get the car to "tuck in". Lifting off is absolutely the wrong thing to do in a Scoob.

Make sure your geometry is correctly set. Py a visit to Micheldever Tyres (ring to book) and get their 4 wheel alignement set up done (they call it Prodrive). Mke sure that your tyre pressures are correct (I find a 3 psi differential front to back works well).

Bump steer will help under braking but will not help the issue you describe, Powerstation do the alignement at the same time as the Bump steer, its why its so expensive. Will cost around £45 for Micheldever to do the setup. (not bumpsteer though)

BTW you can buy the kit to measure bumpsteer from Demon Tweaks if anyone is keen to diy.

Its not easy getting used to applying throttle to get out of sticky situations and you need to be circumspect but that is the way the Scoob works.

ScoobyDan

Thanks for the prompt replies!

I think I will get the alignment looked at, as I have noticed a tendancy for the steering wheel to try to center with a slight left bias (as though the tracking was out) - they could be connected.

Daniel

MichelleWRX1994

I would recommend having your geommetry settings looked too.

dfullerton

BOb is right never lift off mid way through bend. allways apply more power as you go round, Takes awhile to get used to =============

simonma

When ever entering a corner / rnd-a-bout always have low to mid revs. Then ease the power on (never suddenly) once you see the exit from the apex.

If you understeer usually means you have gone in too quickly with no power to the wheels.

my ten p's worth

ScoobyDan

Thank you Simon for that very comprehensive reply

After seeing you on Top Gear I will take your advice as Gospell!

I have done a days training at Goodwood racing circuit (a good few years ago now ) and this year had a day on a skid pan. I think some further education is called for...

Thanks again to everyone

Daniel

MichelleWRX1994

Woohoo Simon has posted

Words of wisdom Si you gonna consider a video?????

EvilBevel

OK, I'm not a driving God (I managed about 3/4th of the MIRA circle before spinning back right onto the parking lot at Little Chief LOL), but I would like to comment

1) throwing money at problems is making problems more expensive ... an alignment checkup is always good, and is preferably done before you do a walz on a roundabout, but leave the other mods for later

2) new tyres: you have to treat new tyres as being totally unreliable. SO2's are about the worst I ever had for this, the first 1000 km they were really silly with no grip at all, so you start wondering if everyones advice was completely off ... after that you find that they are indeed amazing. You just have to take this into account, and leave the high speed stuff for after they are bedded in. The Toyos seemed to bed in a bit quicker.

3) the Impreza is not a wonder on wheels, in fact, the grip is quite modest (comparable to Peugeot 306 etc). What it does have is a) very good traction and b) the car reacts brilliantly to small inputs/gives you lots of feedback. You mentioned third gear, so your powerband would have been something between 80 km/h and 130 km/h ... that is *very* fast for a roundabout, especially on completely new tyres.

4) lift off oversteer is what would "normally" happen, and let's not confuse that with the nice powerslidey stuff, it really does catch you out. But in your case it didn't happen, and there could be xyz factors that caused the understeer to continue. But basically, a car reacts to inputs: give it a very BIG input (like lifting off at the limit, probably steering more into the corner) and you will get BIG reactions, sometimes totally unpredictable. The car is no longer the star rally AWD icon at that point, but a helpless 1.2 tons of steel with 0 wheel drive.

5) slow in slow out is my style LOL, but yeah, try to build up your speeds more gradually, and see how the car reacts to little inputs. Remember you are not on a special stage, but on a public road, and sometimes need to react to traffic situations. Keep a safe margin. I would now suggest to book a session at MIRA with Don Palmer, but I am not sure if that is still available Try contacting him anyway, and see if he can do a 1 to 1 tuition.

6) it is OK to be slow in an Impreza, don't think you have to be Burns/McRae etc all the time. It's your car and your life. It takes a while to find how the car reacts to all the inputs, and modding it constantly will make it harder to read the car. Be patient, the car is as good as it says on the tin, but there is a (constant) learning curve. Don't confuse bravery with car control.

7) to end with a positive note: you did get the car back under control, so your reactions are sound. Sometimes locking up your brakes is the only thing you can do to prevent making a big hole in the scenery (and sometimes it's a guarantee for making an even bigger hole ...).

Theo

EvilBevel

Forgot one thing I wanted to say: with this weather most normal road tyres are next to useless, as they never get to normal operating temps. At the same time, this weather will give you about 10 to 20 BHP more than in summer, so be extra careful.

RichS

One other thing to consider...
(By no means contrary to the excellent advice so far.)

Applying too much steering lock (steering too much) may also have contributed to the understeer in this situation.

It's a common mistake (I'm no driving expert so I do it all the time!)

If you turn to wheel too much, as a natural reaction to the first signs of understeer, the result (depending on speed, road surface, tyres etc etc) may be that the car understeers even more.

Advanced driving lessons on handling/limit control with someone like Don Palmer will help you understand this better in a relatively safe environment.

Rich

ScoobyDan

Theo,

Thanks for your comments, but just to make sure no-one thinks I'm a nutter entering a roundabout at circa 100KPH I would like to confirm that the road in question has a 40MPH limit, so when I dropped to 3rd I slowed to approximately 20-25. With hindsight, that was probably still a bit too fast for the roundabout in question... Still, we are always learning new lessons, and my one is to enter roundabouts with a bit more respect!

Daniel

Canuck

This thread deserves a lot of attention because I am sure that the majority of us haven't a clue what we're doing behind the wheel, particularly in a car like ours, where I feel that it just waits for instructions on bends and does exactly what you tell it too, with me all to often having to resort to yet another bottle of fabric cleaner to clean the seat after I luckily extract myself from a near-miss !!
I for one would benefit tremondously from 1:1 training, but don't know where it can be found for realistic costs (bear in mind that some of us have scrimped and saved to afford these things in the first place and need careful budgeting, and negotiation with the "accountant", for serious expenditures).
Michelle may have been joking about SdeB's driver's education and a video, but I'll bet there is a market for an SIDC's version that would assist some of us - it lookslike there are plenty of people with expertise in the club. In the meanwhile how can you get in touch with people like this Palmer, especially if you live in the East Midlands and can't go far for such frivolities ?

Canuck

RichS

Don Palmer's web site is:
http://www.drivingdevelopment.co.uk/

Hope this helps...


Rich

EvilBevel

Daniel, just for the record I was honestly not typing all that lot because I thought you were a nutter But at 25 MPH, I'd probably be in 2nd gear, so I could give it some instant throttle if needed. In 3rd at that speed, you might find a bit of turbo lag, which would make it even more complicated.

Canuck, a video would be nice, and you can also visit SDB's other little project at http://www.drivingtechniques.co.uk for more elaborate info.

But ... it's a bit like watching a video and then learning to play piano ... you have to actually do this, and even if it's expensive( like an off isn't ), it's normally well worth it.

The magical roundabout at MIRA was fantastic for this, because you could lose the car completely without much change of damage etc... and start to get a feel what the car tels you before it goes into understeer/oversteer/4W drift etc.

Sure bring on Simons video, but I feel more for the big "LOOS course" at Bruntingthorpe we talke about eons ago.

Maybe an idea for SIDC to organize it so Simon only has to play & show ? It would be a great thing for those who want to improve their driving without wanting to go on a track (where you can feel lost as well BTW)

Theo

Davvers

whilst agreeing totally with Simon on this - I've noticed that most roundabouts have adverse camber so that rain water flows away from the centre of the round about to the edge - if you take the 'racing' line through, you can end up driving over a slight hump or rise, I have found if you are near enough the limit this can upset the balance enough to upset one or both ends. I find the front tends to lighten first and can start the understeer. A very gentle lift can help in some situations here - or light application of the brake LFB - like almost everyone has said this is best practiced in wide open areas - and Mr Palmer is pretty good at pointing you in the correct direction - no pun intended

DavidRB

Dan, just sounds like you went in too fast, didn't get enough grip at the front, so you turned the steering wheel tighter, making the problem worse by inducing even more understeer. As pointed out, 3rd gear was too high for that speed, you would have been a long way off boost in a WRX. New tyres & a crap road surface lower the speeds at which you slide, but the behaviour will still be the same. 4WD helps you accelerate out of corners quicker, it doesn't help you go into them any faster!

Simon's the god on this stuff, so read his posts well.

For what it's worth, my view is that you can't drive a 4WD car like it's a FWD or a RWD car, which is what I think most people who complain of understeer are doing. When cornering, if you apply more throttle in a RWD car, it can make the back end step out, in a 4WD, you're more likely to get understeer or neutral steering.

I find that I have to turn the nose of the Scooby in a little tighter than seems natural and then use the throttle to push the car sideways ("away") from the inside of the bend. If/when the back end does start to slide, you have to resist the temptation to lift off and opposite lock, just keep your nerve, ease the throttle back a touch, point the wheels where you want to go and let the Scoob do the hard work.

Stick to big empty roundabouts at first though!

sulli

To be honest, considering the speed you say you were going, I think it highly likely that a slippy surface was the cause - and this is something you can do little about, except treat all sharp bends/roundabouts with extra caution in this weather.

Apparently, in weather like this, apart from stuff like slippy leaves on the road, rain brings deisel to the road surface, making it like ice. Diesel tends to spill from HGVs etc on sharp bends where it sloshes out - making them all the more dicey. I had a similar thing happen to me in my 1.9 gti last week - a fairly inocuous 90 deg bend, taken at maybe 15mph, and the front end didn't want to turn, just eased off, waited for grip, and tried not to brake or turn wheel to much - luckily regained control. In the dry that could've been taken at maybe 40mph in the Pug!

One thing that really bugs me though in this weather is ppl driving round in tinpot motors with diddy 135 tyres sometimes get more grip on wet/slippy surfaces, and make me look silly

I wouldn't worry too much - the best advice I can give is Slow In Fast Out - once you've found your grip level feed the power and pull out of the corner.