Thứ Sáu, 20 tháng 1, 2017

How to Initiate a Turn in Snow part 1

williaty 02-12-2007 09:23 PM

How to Initiate a Turn in Snow
Hello,
If a mod thinks there's a better forum for this, I'm game. I'm posting this in Motorsports because TSDs are where this affects me the most. On the road I can just crawl around like a grandma in a Buick, but for a TSD, I'm trying to maintain a CAST value.

My problem is that I'm having trouble initiating turns in snow. Once I get the car starting to turn, I can deal with it just fine, adjust the slip angle, tuck or widen the line, etc. It's getting that first little tiny bit of rotational inertia that I can't figure out. My prior car was a high-torque, low rear axle load, rear wheel drive truck. In order to make the car turn in snow, all I had to do was turn in while lifting, wait for the back to start to step out, then control the amount of rotation with lock and throttle. Once I get the Subie rotating, the same control applies. I've tried everything I can think of to get the rotation started. Lifting. Goosing. Brakes. Big inputs. Small inputs. Various combinations of timing. Even the Scandinavian Flick doesn't work because I can't get the car to transfer weight on the away-from-turn part of the setup. Basically, I've got no joy on any of them. The only thing I could find that worked most of the time is to turn the wheel into the turn slightly, goose the gas, immeadiatly lift, then immediately stomp on the gas until rotation happens, then moderate the throttle and lock.

The problem with that technique is that it makes the car push wide initially. This isn't possible on some of the narrow 1-lane roads the TSDs around here can be run on.

What am I missing? How do I get this thing to turn in in the snow?
KC 02-12-2007 09:29 PM

Good snow tires? Turn-in and immediately a quick e-brake lift and release?

-kC
williaty 02-12-2007 09:34 PM

I've an RS. Handbrake locks up rear end, which locks up center diff, which locks up front end, which doesn't help turn.

As well, I'm not serious enough about winning TSDs to justify the cost of snow tires just for the 200ish miles a year I might want them. All seasons get the job done most of the time considering we don't often see that much snow and ODOT usually gets rid of it pretty quickly. Just not on the roads TSDs get run on.
leecea 02-12-2007 09:34 PM

TSDs in the snow that require this type of driving - do they really exist?
williaty 02-12-2007 09:35 PM

lecca, some of the TSDs will have CASTS of maybe 20mph. That's enough to be work on roads that narrow.
KC 02-12-2007 09:43 PM

That's why I said turn in and *quick* e-brake... get some weight transfer to the front wheels in a turn and just do a quick one.

On loose surface, it won't hurt much. You're not going to yank it and hold it up... just a quick jab when you turn.

--kC
boostpower 02-12-2007 09:45 PM

Find an big empty parking lot and play! And I don't think the handbrake locks the fronts also, just make sure you clutch when you do it. I've noticed in my car (04 WRX Wagon), all it takes is a little gas to get good rotation. No need to stomp it, just a little gas and then proper stearing to keep the car going where you want it. A little flick seems to really help my car rotate also. I do have a bigger RSB so I don't know if that's helping me at all or not.
Storm 02-12-2007 10:36 PM

I'd disconnect the front sway bar and see if that doesn't help. You're going to need good tires at least up front to have any sort of control as most of the torque is going there anyway. If you're not using GPS for navigation, you're losing at least some accuracy when you start spinning the wheels through a turn...but you probably already knew that.

If you keep steady or even add throttle while you quickly jab the ebrake to initiate a turn, it'll minimize the front braking effect of the center diff. It's not that strong to begin with.

Jay Storm
hotrod 02-12-2007 11:11 PM

slow in fast out ----

start you turn farther back from the corner, and don't over cook the turn.
On snow you can't make sudden abrupt moves, so act like your driving a bus, swing wide early and start the turn in motion with just a little steering lock. Widen the turn radius as much as practical.

Once you have started the turn, and the car is in a gentle curve it is much easier to kick out the rear end. The WRX is tail happy enough that a quick blip on the throttle will step out the back end if you have a bit of turning load already developed with a long gentle corner entry.

You will lose much more time fighting a push from too much entry speed than you will give up with a longer approach and wider radius.

Larry
RB5 Clone 02-12-2007 11:11 PM

your cheapness is not helping. "I'm not serious enough to buy snows, but I want to win in winter" is classic oxymoron logic.

to turn on snow, you need grip. to get grip on snow, you need tires. SNOW tires. "all-ski-son" tires just make the push worse--exactly what you do not need

once you have the right tires, realize that you must be patient. everything takes longer on snow.

you cannot turn-in-NOW on snow like you can on tarmac. start turning before you get to the turn.

Your descriptions of what you're trying sounds like you are doing too much at once for your available grip. go for smoooooth inputs. you only have so much grip, which can be used up by steering, throttle, or brakes (or worse, 2 or more of those at once). on snow you can basically only do one thing at a time. lift, turn in (turn in EARLY and be patient, it'll come around), maybe dab a bit of left-foot brake to help the rotation then RELEASE BRAKE, be ready for quick countersteer, back on the gas gently. Once you feel the pattern start to work, repeat until you run out of road. Start slowly, otherwise you'll just end up going off said road. ;)

if you're getting too much push, try less steering angle...you might end up pleasantly surprised.

I teach performance winter driving. those who come to the course with the wrong tires and a "need to turn NOW" attitude usually take 2x-3x longer to unlearn tarmac habits and get it on the slippy stuff. ;)
williaty 02-12-2007 11:49 PM

[QUOTE=RB5 Clone;17030858]your cheapness is not helping. "I'm not serious enough to buy snows, but I want to win in winter" is classic oxymoron logic.

to turn on snow, you need grip. to get grip on snow, you need tires. SNOW tires. "all-ski-son" tires just make the push worse--exactly what you do not need

once you have the right tires, realize that you must be patient. everything takes longer on snow.

you cannot turn-in-NOW on snow like you can on tarmac. start turning before you get to the turn.

Your descriptions of what you're trying sounds like you are doing too much at once for your available grip. go for smoooooth inputs. you only have so much grip, which can be used up by steering, throttle, or brakes (or worse, 2 or more of those at once). on snow you can basically only do one thing at a time. lift, turn in (turn in EARLY and be patient, it'll come around), maybe dab a bit of left-foot brake to help the rotation then RELEASE BRAKE, be ready for quick countersteer, back on the gas gently. Once you feel the pattern start to work, repeat until you run out of road. Start slowly, otherwise you'll just end up going off said road. ;)

if you're getting too much push, try less steering angle...you might end up pleasantly surprised.

I teach performance winter driving. those who come to the course with the wrong tires and a "need to turn NOW" attitude usually take 2x-3x longer to unlearn tarmac habits and get it on the slippy stuff. ;)[/QUOTE]

OK, point taken on the cheapness. However, I have no expectation of winning. It's more "I want to be cheap but I don't want to be so frustrated with my poor driving that I eat my hat". I'm totally driving these things to have something to do, not to beat other people.

The size of the control inputs is something I had considered I was doing wrong, hence the experimentation with different sized inputs. It's obvious to feel that the traction circle is smaller on snow. You can feel that you can get much smaller steering angles before the front end starts to skid and much smaller braking inputs before everything begins to skid. This did lead to me learning to use smaller steering angles last practice session. However, at some points, it felt like turning the wheel AT ALL resulted in skidding in a straight line. As an experiment, I tried to shift some load to the front end to turn with, but that didn't seem to work either.

Again, once I upset the chassis in any way, I was able to exploit that to make the car do exactly what I wanted.

Your unleaning comment is probably quite relevant. In this case, however, I suspect I'm trying to unlearn my last car more than unlearn tarmac. God my last car was good to drive in the snow...

It looks like we're getting 8" of snow in the next 12 hours. Sounds like I'll have a chance to try what you're talking about tomorrow.
hotrod 02-13-2007 01:12 AM

[quote]However, at some points, it felt like turning the wheel AT ALL resulted in skidding in a straight line. As an experiment, I tried to shift some load to the front end to turn with, but that didn't seem to work either.

[/quote]

You were just going too fast for the tires and traction available. If you start understeering with the steering inputs you need, than you need to slow down on entry (or get more grip).

Keep in mind that there is no one snow condition. Available traction can have a huge range depending on the character of the snow fall (wet or dry snow) temperature (conditions are slicker near 32 degrees than they are at colder temps), tires of course. For what you are discribing you need some legitimate snow tires, look for the snowflake and mountain stamp on the sidewall that shows it is a true snow tire not an all season.

There are some reasonable priced legitimate snow tires.

Larry
williaty 02-13-2007 01:36 AM

Honestly, I've been coming to the conclusion that I need some real winter tires too. The new high performance one from Bridgestone that's supposed to be a tire biased towards winter dry tarmac that can still hold its own in snow and ice sounds attractive. I have the Pirelli PZero Nero M+S's right now. It kind of baffles me that they don't do well in snow because the last tires I had before the Subaru were Michelin LTX M+S's, so I kind of expected similar snow grip from any M+S tire. Buying new wheels and new tires just for 2-3 months out of the year is just so much money though. Yeah, I know I'm cheap.

The problem is that even on less than ideal tires I feel that I should be able to drive around the limitations of the car. The whole tighten the nut behind the wheel first thing.
hotrod 02-13-2007 01:58 AM

If your driving in real snow vs on hard pack or ice, you need an agressive lug true snow tire. The discription above screams (intended for dry pavement in the winter, but not quite totally useless in snow).

The all season and multi use tires generally mean they are equally poor in both areas.


You might want to poke around this web page a bit

[url]http://www.snowtire.info/[/url]

Larry
Storm 02-13-2007 02:27 AM

You can't be gearing up for the Ohio Winter Rally...cuz it's gone and passed. What rallye are you getting ready for? It might not get too bad with snow down by you but the few times it does...you'll thank yourself for spending as little $400 on a used set of steel wheels and dedicated snow tires. Even the cheapest sears winterhandler's will be a huge improvement over an all season tire. I've had more fun doing the OWR on cheap snows than people should be allowed to have. I love it when my co-driver would get us lost so I could make up time on roads I grew up on. Outdriving the cheap 6" KC knockoffs through the twisties is an absolute hoot! Of course I'm not good enough to keep from having the occasional pucker moment!!! Is there such a thing as red mist driving on snow? :D

Definately starting the inputs way earlier and much smoother is the way to go. Is your RS pretty much stock? Do you have it setup for dry weather handling with springs, bars, struts, etc? This will also have a huge effect on what you'll be able to do in the snow. The car should be on stock springs with stock bars or no bars. That will slow down the weight transfer, giving the tires more time to work before getting overloaded for available traction.


Jay Storm
XenoWolf 02-13-2007 02:28 AM

Left-foot braking. Stay on the throttle, but give it enough brake to transfer the weight off the rear end and onto the front. The flick usually works well for me, but you want to start braking (assuming you're not doing so already) on the "turn away" part, then let off the brakes and power through the "turn in". I've hardly perfected it, especially since we've had zero snow this year here, but it usually works fine for me. Oh, and yes I'm running snow tires.
boosted_rs 02-13-2007 08:02 AM

Get snow tires. Even used one will make a huge difference. Plus they will cost you next to nothing and make it much safer and pleasant for you.

Trying to stop in the snow with all-season tires is useless.

Anybody that has not tried proper winter tires just won't get it.
KC 02-13-2007 08:07 AM

[QUOTE=boosted_rs;17033664]Anybody that has not tried proper winter tires just won't get it.[/QUOTE]2nded, 4thed, 10thed... etc... ad infinitum.

You're just causing your own issues by running all seasons. For all I can read from your posts, you look to be doing most things right. It's the tires holding you back from fully accomplishing what you're striving for.

So you have 2 options...

1) Keep doing what you're doing, and suffer what fate resides around the next corner... or
2) Get snow tires, and do the happy happy joy joy dance.

No amount of driving by someone doing this on a casual level will make all seasons behave like snow tires, never mind being a superstah driver.

--kC
Rexfan 02-13-2007 08:19 AM

I guess you could put snow's on the front and raise the rear tire pressures FTW :)
RB5 Clone 02-13-2007 08:37 AM

[QUOTE=Rexfan;17033777]I guess you could put snow's on the front and raise the rear tire pressures FTW :)[/QUOTE]

umm, negative on that solution...unless you like the combo of pig-like understeer followed by wild snap oversteer.

reading OP's posts so far, it does sound like his main issue besides the tires is trying to go too fast for prevailing grip. speeds in snow are sharply slower; say a certain stage road on gravel the average speeds over like 7 miles are in the 55-60 range; same road in snow might be 35 or less.

again, BE PATIENT and smooth.

and if your car is set up for autox, ditch those stiff bars, they are complicating your life on snow. softer setup helps emphasize the weight transfer you need.
randy zimmer 02-13-2007 11:12 AM

Next time you buy tires, and with Pirellis, that won't be long from now, get Nokian WRs, The snow tire that works in the summer.
This is the only true all-season tire. I have quite a few customers on it.
Next, despite all the ridicule he got, the "turn in low-grip" guy had it right all along. If you saw the wheel on the straights, the turns work better. Once our cars take a plant, they're hard to get turned.
For a good example - find the in-car of Patr at Camp Brulie, even on a 3 mile straight, he never stops sawing.
randy zimmer 02-13-2007 11:43 AM

[QUOTE=leecea;17029553]TSDs in the snow that require this type of driving - do they really exist?[/QUOTE]

[url]http://www.flr-scca.com/rally/2007/index.html[/url]

EVENTS & SPEEDS
The Winter Rally Series is in its' 25th season in the Finger Lakes area. Designed to provide enjoyable competition for every level of rallyist, the series allows choices.
"Tulip" diagrams (a line drawing of each intersection) and a mileage at each turn, provide an easy-to-follow course. The challenge is in the road surfaces and weather conditions. Primarily unpaved back roads are used (usually roads plowed in winter), and we hope for snow. To allow rallyists to compete where they feel comfortable, we utilize 3 speed groups, and "seed" drivers based on prior experience and performance. Only the most experienced, proficient drivers compete at "A" speeds, usually 45 MPH. Novices start at "C" speed, 36 MPH; the majority compete at "B" speed, or 40 MPH. In very bad weather, each group may drop to the next lower speed (C becomes 33). To equalize competition between speed groups, a factor is applied to the raw score based on the competition class and speed group to determine final score.
Joshw 02-13-2007 11:48 AM

[QUOTE=randy zimmer;17035534]
Next, despite all the ridicule he got, the "turn in low-grip" guy had it right all along. If you saw the wheel on the straights, the turns work better. Once our cars take a plant, they're hard to get turned.
[/QUOTE]

Randy is exactly right. If you keep the car just a little upset on the straights, it is always easier to initiate a new turn than if you are going straight with no slide. In a pigish car (all cars are pigish to some degree) like my 1980's audi wagon, if that thing isn't swinging back and forth down the straights, you will never get it to turn in.
REX8 02-13-2007 12:30 PM

[QUOTE=williaty;17032309]Honestly, I've been coming to the conclusion that I need some real winter tires too. The new high performance one from Bridgestone that's supposed to be a tire biased towards winter dry tarmac that can still hold its own in snow and ice sounds attractive. I have the Pirelli PZero Nero M+S's right now. It kind of baffles me that they don't do well in snow because the last tires I had before the Subaru were Michelin LTX M+S's, so I kind of expected similar snow grip from any M+S tire. Buying new wheels and new tires just for 2-3 months out of the year is just so much money though. Yeah, I know I'm cheap.

The problem is that even on less than ideal tires I feel that I should be able to drive around the limitations of the car. The whole tighten the nut behind the wheel first thing.[/QUOTE]


Well, the Pzero's have a reputation for being prety poor in the snow...so don't expect much. The pilot A/s on the other hand are supposed to do VERY well compared to dedicated snow tires. Maybe look into them for your next set. Until then, slow down a little.
leecea 02-13-2007 02:36 PM

[QUOTE=williaty;17031300] It's more "I want to be cheap but I don't want to be so frustrated with my poor driving that I eat my hat". [/QUOTE]

I can relate to this. I have been trying to practice good snow technique in empty lots but have been unable to do anything except slide around with little control. I'm using my original RE-92s as winter tires and have Konis and a big FSB for autox. This thread will be a big help with technique, but I know my setup means slow and extra slow are the only viable speeds :(
dch 02-13-2007 03:59 PM

[QUOTE=leecea;17038524]I can relate to this. I have been trying to practice good snow technique in empty lots but have been unable to do anything except slide around with little control. I'm using my original RE-92s as winter tires and have Konis and a big FSB for autox. This thread will be a big help with technique, but I know my setup means slow and extra slow are the only viable speeds :([/QUOTE]

In a stock 2002 2.5 RS with RE92's during our Minnesota winters I had trouble turning into parking spaces at the office because the car would push on me. Swap on a set of dedicated snow tires, and I could negotiate the parking lot oval in a full drift, complete with pendulum turn after the long sides as they were just a tad bit too long to hold the car sideways the entire length. Then they plow the lot and I have to wait for it to snow again :(.

It's worth practicing on the RE92's so you scare the crap out of yourself and therefore learn that you have to drive really really slow and deliberate in snow/ice conditions in anybody's car with all seasons on. It may help your performance driving somewhat. But to really experience controlling the car on snow and ice as opposed to the car controlling you, you've gotta have dedicated snows 100% yes for sure uh-huh doit no question duh it's a hoot!

Get a set of Hakka's on some cheapo rims and do the swap when the white stuff starts coming down, then reverse it at the end of the silly season. It makes winter oh so much more fun.

Cheers,
-Doug
gerald06sti 02-14-2007 02:59 PM

I have the Nokian WRs on my STI. Love them in the snow and rain. Dry performance is good too.
Snowphun 02-14-2007 04:14 PM

[QUOTE=williaty;17032309] I have the Pirelli PZero Nero M+S's right now. It kind of baffles me that they don't do well in snow [/QUOTE]

I have these and they are terrifying in the snow. I take them off before the snow flies and use snows. The only part of these tires that is all season is the rubber compound, it's OK at lower temps. The tread pattern offers nothing.

Cheap snows are in the $65 each range, along with a cheap set of WRX alloys (<$200) and you're good to have a lot of fun.
Howl 02-14-2007 04:42 PM

[QUOTE=williaty;17032309]Honestly, I've been coming to the conclusion that I need some real winter tires too. The new high performance one from Bridgestone that's supposed to be a tire biased towards winter dry tarmac that can still hold its own in snow and ice sounds attractive. I have the Pirelli PZero Nero M+S's right now. It kind of baffles me that they don't do well in snow because the last tires I had before the Subaru were Michelin LTX M+S's, so I kind of expected similar snow grip from any M+S tire. Buying new wheels and new tires just for 2-3 months out of the year is just so much money though. Yeah, I know I'm cheap.

The problem is that even on less than ideal tires I feel that I should be able to drive around the limitations of the car. The whole tighten the nut behind the wheel first thing.[/QUOTE]

Not all all-seasons are created equal. The ultra-high performance ones in particular are poor on snow. But even with good tires you have to adjust your driving style.

I was in a winter rallyX this last weekend. There was a really tight course (1st gear all the way). Even with really good snow and ice tires (Toyo Garit HT's) my car was understeering like a pig. My driving style is to stay on the gas in an understeer situation. I was cursing the whole way round, but I ended up with comparitively good times. I guess other people were having even more problems.
Snowphun 02-14-2007 05:25 PM

1st gear course? :huh: Was it someone's driveway?
Howl 02-14-2007 05:42 PM

No. The track of the driveway was 60/70 kmph (40/45mph). The other track was in a parking lot around a bunch of trees.

It was 1st gear for me (4EAT). Some people were getting into second for a few seconds. It was probably 30kmph (20mph) max.
ROC pit-bull 02-15-2007 01:33 AM

I saw this topic but I havn't read the above yet....

the best way to do a turn in the snow is, take the corner as wide as you can. Use the foot brake and gas. This should turn the car quickly, If it doesn't turn eneough use the hand brake quickly to finish the cars rotation.

This sounds confusing to me and I'm typing this :)

Just practice every chance you get.
Storm 02-15-2007 02:31 AM

I had ample time to test out a few of the different methods for turning in, thanks to the deluge of snow we got over the past couple days. For my car, which is still way too stiffly sprung for winter use, I had to simply slow early and apply smooth steering inputs. As soon as the front would begin to bite, I could get back on the gas to power through the turn in pretty much any angle of attack I wanted. Constant sawing on the wheel to keep the car upset works pretty well too...but I was on public roads, so I sure as **** didn't want to get pegged for dangerous driving.

One thing I did notice is that with decent snow tires (Hankook I'Pike) I'm getting up to speed very quickly which, obviously, made turn in more difficult. Depending on the turn and situation, upsetting the car early seemed like a pretty good approach for squirting around tight corners. Handbraking works really good too when used with a purpose and only for a moment. Just enough to make the rear move, then back on the gas to power through.

Oh yeah...AWD only works when all wheels are on the ground!!!

Jay Storm
ROC pit-bull 02-15-2007 03:00 AM

AWD also works while air born, just no control on where you go. :)

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