3rd gear Subaru wheelspin

3rd gear Subaru wheelspin

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GravelBen

Original Poster:

15,695 posts

231 months

Monday 5th June 2006
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yep, thats right, my wagon had all 4 going in 3rd. and nope, I haven't repowered it - but we got some snow last night - great fun

not much settled in town, and its mostly melted now, but it was fun while it lasted, and had a few laughs and some sideways action on some of the twisty roads up the hills close to town.

unfortunately a mate stuck his Nissan Stagea into a ditch/bank in the process, the computer-controlled 4wd was a bit too clever for its own good. We came around a fairly tight right-hander, bit of understeer so he gives it some boot to swing it round, nicely sideways, then back the other way into a gentle left, he's still got the foot down sliding it round, then what seems to have happened (based on end results, inspection of tyre marks etc) is one of the rear wheels ripped through the snow into the gravel below it, and the ATTESSA computer went "ooh, that wheels got traction so I'll send more torque that way". but the front wheels were still on top of the snow and not being given much power, so the back end just pushed itself round and nosed the car straight into the ditch with a BANG, followed after a brief pause by a "BUGGER"

It munted the bumper a bit and smashed a headlight, but could have been worse. We managed to dig enough of a ramp behind the front wheels (with a jack as he didn't have much else) to back it out and drive home (very sedately) which was good, otherwise it would have been a rather cold half-hour walk to get the Subie and tow him out.

The other thing I learnt last night, this one while driving my car down a fairly steep, pretty slippy hill, is that ABS is really not a good thing in snow (this being my first car with ABS). Doing the usual sporadic grip-tests coming downhill, I was able to stop pretty easily by modulating the pedal myself. And then I thought, hmm I wonder how the ABS goes, and hit the brakes harder - it stayed in a straight line, and the pedal juddered away at me, but it didn't actually stop - at all, until I released the brakes past the ABS point, when it stopped fine.

So, lesson learnt from last night: fancy electronic stuff really doesnt help on very slippery surfaces. At least not the fancy electronic stuff they fit in normal cars.

Kiwi XTR2

2,693 posts

233 months

Monday 5th June 2006
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The latest electronic wizzo stuff for ABS, Traction Control, Yaw Control has different surface maps and adjusts accordingly. Some even have a doppler radar hooked in.

I'm firmly of the belief that, although these gadgets help in an everyday 'emergency', they are detriment to gaining real car contol experience at anything above 7/10ths.

My Westie is the first car I've owned in the last 11 years that hasn't had ABS, 4WD, 2000cc, & a turbo . . . or a roof

htsd

263 posts

241 months

Monday 5th June 2006
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4WD cars are a different beast entirely when it comes to getting sideways because frankly they're not meant to be that driven that way- if you are going to do that you really want a locked centre diff so you don't get into that situation or have the electronic trickery properly trained.

Remember the Murcielago that was stacked in Parnell a while back? I reckon thats what happened there- driver had TC off, gunned it, back got out, opposite lock to correct and the power suddenly went to the front wheels and hauled it off the road into the fence. I've nearly done it myself in an old Evo 1.

Kiwi XTR2

2,693 posts

233 months

Monday 5th June 2006
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To be honest (for a change) I'm not entirely convinced about all these stories of massive power transfers around the various wheels of a 4WD. I know it happens - it's happened to me, but you do need your boot fairly well up it!

I would think that most of these, particularly the amateur, occurrences might have a little more to do with lift-off oversteer.

GravelBen

Original Poster:

15,695 posts

231 months

Monday 5th June 2006
quotequote all
It depends on the particular system, the electronically controlled ones do it, but the mechanical systems (like Subaru stuff) don't really. At least for moving torque split between front and back, I don't know if any of them do side to side, most powerful ones just have front and rear lsd's which could technically be considered torque transfer, looking at from a particular way. (open diff will let one wheel spin power away, if no grip then no torque just free spinning, once it locks all the torque through that axle can go through one wheel, the torque is where the resisting force is, ie friction. if that makes sense, its not explained very well)

The Stagea that was mentioned before definitely does (Nissan ATTESSA system, very simliar to the Skyline GTR), you could feel it earlier that day around a wet/sleety hairpin, on constant throttle (according to the driver) you could feel it shuffling backwards and forwards between understeer and a hint of oversteer as the computer moved the torque between front and back trying to find some mroe grip.

Having looked at the marks on the road immediately afterwards, only one of the tyre marks had ripped throught hw snow to the gravel, and it was the furthest out, therefore rear right as we were a bit sideways at the time. I'm pretty sure he didnt lift off until he had no chance of recovering it, the guy knows what he's doing and has clocked up plenty of sideways gravel miles in that car. Its an auto though, so it may have tried to change up on him which would have same weight transfer effect as lifting off. I think its a pretty rear-biased 4wd system which probably wouldn't help once it did let go.

No such lack of predictability from the Legacy though, just a bit more understeer than I expected - in normal driving it has less understeer than the old Legacy, but felt like a bit more in the snow. With the old one in slippy stuff I just used the old scandinavian flicks to get round it, but this ones worth a bit more so I've been making myself be a bit restrained in it, just staying smooth and provoking a bit of sideways with the gas rather than risk over-commiting and breaking it.

Kiwi XTR2

2,693 posts

233 months

Monday 5th June 2006
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Didn't mean to suggest it didn't happen to your buddy Ben.

It's just that as an excuse it's becoming about as predictable as a certain NZ Rally driver claiming - "We had a problem with the anti-lag technology . . ."

GravelBen

Original Poster:

15,695 posts

231 months

Tuesday 6th June 2006
quotequote all
Kiwi XTR2 said:
Didn't mean to suggest it didn't happen to your buddy Ben.

It's just that as an excuse it's becoming about as predictable as a certain NZ Rally driver claiming - "We had a problem with the anti-lag technology . . ."


The favourite Rallying excuse at the moment seems to be "We're having problems with the centre diff"

I agree with you in general though, the torque transfer only seems to be feelable right on the edge of traction, so you'd need a fair bit of power and the boot hard up it for it to have any effect on remotely grippy surfaces.

Most of the AWD car spins/crashes do seem to be a combination of overreacting and winding on way too much opposite lock, and/or lifting off. (hence giving a lot of grip to the front wheels which are now pointing in completely the wrong direction). Its surprised me a few times me the situations you can get yourself out of with 4wd by just keeping the wheels pointed where you want to go and giving it some beans.

But I have been thinking that once I finish uni, get a decent job and have some spare cash floating round I might have to buy a cheap, light RWD car and learn to drive properly.

Mustang-man

255 posts

222 months

Tuesday 6th June 2006
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On the way to Christchurch yesterday in the Mazda (MS-6, front wheel drive, hatchback, V6 with not enough power) we saw snow everywhere, but most had been melted, as we left at about 9:30am. Brother took the below pics as i was driving.










Did the handbrakeys, as mentioned below, on the other side of this hill.

It was the first time i've ever driven in snow. As we were following cars going way too slow down the four lane hill thing (where the road goes straight across the valley after it used to curve all around it, and where the 'wind gust' warning signs are - on the other side of the hill from the last pic above) i decided to have a bit of fun in the snow, so drove into the stuff on the side of the road that no-one else had driven on and proceeded to pull the handbrake.

Didn't think it worked (no sound or anything) until i felt the back end getting out a bit. So drove up a bit further and did it again, this time getting way more sideways (fun! ). It is so weird though, you pull the handbrake on and don't notice a thing, there's no jolt and no feeling that the back tyres are locked until you feel the back of the car sliding out. Quite cool.

I didn't do it again after that because as we were approaching the part of the road that goes right over the valley we saw a tow truck on the other side of the road with a police car pulling up behind it. As we got closer we could see a Nissan Primera right behind the truck and it had a fair bit of damage on the front (like it had gone down the hill too fast, understeered and slid on the snow, hit the bank and gone down the ditch).

It was also almost completely burnt out. So it was possibly an American import Primera...

Snow = fun.

Oh and from Christchurch to Dunedin it took me about exactly four hours doing 110 most of the way (because i didn't want to be driving all morning, and we were lucky to see one car/truck every half hour). Including a petrol stop in Timaru.
Left at roughly 9:30pm and got into the Dunedin area at about 1:30am (got home at 1:55am).

GravelBen

Original Poster:

15,695 posts

231 months

Tuesday 6th June 2006
quotequote all
Nice photos there was a fair bit more snow than that on sunday night, we had a few trips up and down Leith Valley rd beside the motorway there and took the Legacy most of the way up Mt Cargill, but decided to turn round at the bottom of the steepest part where a group of 4 bigger 4wd's were turning back as well.

Most of the crashes that happen round here when it snows are the numpties who panic as soon as they start sliding, slam on the brakes and just keep sliding in a straight line until they hit something. Because speed kills, dontcha know, so hitting the brakes must be safest. duh.

robdickinson

31,343 posts

255 months

Tuesday 6th June 2006
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"Drive to the conditions, if they change reduce your speed..."

Kiwi XTR2

2,693 posts

233 months

Tuesday 6th June 2006
quotequote all
robdickinson said:
"Drive to the conditions, if they change for the worse reduce your speed..."

And if they change for the better ? ? ?

GravelBen

Original Poster:

15,695 posts

231 months

Tuesday 6th June 2006
quotequote all
Kiwi XTR2 said:
robdickinson said:
"Drive to the conditions, if they change for the worse reduce your speed..."

And if they change for the better ? ? ?


Reduce your speed, of course. We can't have people actually getting places now, can we?

Kiwi XTR2

2,693 posts

233 months

Tuesday 6th June 2006
quotequote all
GravelBen said:
Kiwi XTR2 said:
robdickinson said:
"Drive to the conditions, if they change for the worse reduce your speed..."

And if they change for the better ? ? ?

Reduce your speed, of course. We can't have people actually getting places now, can we?

I see that stint in Local Government has done for you what it has done for most people

GravelBen

Original Poster:

15,695 posts

231 months

Tuesday 6th June 2006
quotequote all
Shhhhh dont say that too loud! I'm still planning on looking for a job in private practice, and hoping to keep that a secret...


but hey, its a pretty well-paying holiday job anyway

kylie

4,391 posts

258 months

Wednesday 7th June 2006
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Great pics mustang-man!! $hit it must be frrreeezing down there! Learnt a lot how to "attempt" to drive in heavy snow and ice from an old boyfriend who was swiss and used to be a ski instructor (lucky me lol). He took me back to swissyland for a skiing holiday and we got around in a front wheel drive Fiat Uno ($hit box thing)..? Back here in conditions where you would normally use chains, he refused to use them and was just keeping his foot in it all the way up the mountain in the thick snow and ice patches, stopping wernt an option. And coming down he handed the wheel over to me to teach me I refused naturally but managed to learn how to steer down into the corners over taking other cars and pumping the brakes, its a real fine balance before you start sliding as you naturally want to press firmly to slow the car down a bit. But overall its cool to learn something and come out alive without using the chains. Tried it going down Mt Hutt ski rd a few yrs back when the road was a slushy mud pit with compacted ice and seemed to work a treat, that was in a rwd Mazda 626. I wouldnt recommend driving without chains though.