PDA

View Full Version : Regarding AYC n' TCL on snow/ice



Physician
20-11-2004, 08:51 PM
During the recent cold snap I took the VR4 out to see what happens in the snow:sad3:

I have never driven a car with AYC in snow and thought I was going to be in for some impressive control. WRONG !

The 4 x 4 drive obviously helps with traction along with the TCL but I found the AYC to be totally unpredictable as it 'snatched' this way and that in the snow. With a 'normal' car I can predict what is going to happen most of the time but I was totally useless in the snow. I find this a bit odd as I have learned how to get some controlled drifting (slightly) on wet roads and yet it's so completely different on the white stuff. ( Yea! of course it's bound to be different but I figured the AYC would keep it all straight for the best part).

Do you all find the same? Do you rekon it just takes some getting used to and subsequently one can get it drifting (sorry :dozey: ) in snow - a learning curve?

Nick VR4
20-11-2004, 09:18 PM
I would imagine the AYC is trying to get grip etc on the wheels and when it cant it changes to other set up's or styles and goes a bit freaky

I drove mine on long wet grass was ok in a stright line start turning and a nightmare.
Until I got use to it

So it does take a while to get to grips (lol pun) with it

calum
21-11-2004, 02:02 AM
I think it's quite impressive. Ignore the snatching feelings and you will find that you are pretty much going where you want to go - and a lot faster than you would in a 2wd car!

Just have to remember that it can't help defy physics. My main problem with 4wd cars is you can get going easily enough - stopping's a bit of an issue!

Roadrunner
21-11-2004, 09:07 AM
Just have to remember that it can't help defy physics.
A Physician will know that! :-D It does take a bit of getting used to. Generally, lifting off the throttle is what causes the snatching - you need to practice balancing what the car is doing on the throttle, keeping some power in there so the AYC and the diffs can work. Full throttle works, but you need to know what you're doing ;) But if you lift off the throttle, you lose the active control that the diffs and the AYC can provide. Find a nice wide carpark at night and have a play ... :)

Brian

Physician
21-11-2004, 11:42 AM
A Physician will know that! :-D It does take a bit of getting used to. Generally, lifting off the throttle is what causes the snatching - you need to practice balancing what the car is doing on the throttle, keeping some power in there so the AYC and the diffs can work. Full throttle works, but you need to know what you're doing ;) But if you lift off the throttle, you lose the active control that the diffs and the AYC can provide. Find a nice wide carpark at night and have a play ... :)

Brian

Thanks everyone.

Yes H.7 ..... what you say is completely logical (probably why I didn't think about it in those terms). As soon as we get snow again I'll do some more testing! Thanks.

chris g
21-11-2004, 06:52 PM
Yes thats just how it was at the Ring in Aug

Prev I always/nearly always went into bends with a trailing throttle

When it was downpour in Aug, on first day I found car twould snatch and twitch as power went on and off as AYC tried to work then stopped

It snatched partic when I put power on in a bend but next day I made certain in chosen gear then kept throttle on ALL the way into, through and out of the bend

Then it worked a charm and no twitching!

Secret is power on all the time - right amount of power

Roadrunner
21-11-2004, 08:46 PM
Woohoo! Fun and games this morning :) Temperature dropped to -7C last night, then it rained around 7am this morning. Result? Sheet ice everywhere. Main roads slow or closed because nothing could get up hills, lots of minor offs and dunts, and I had to travel 35 miles to play golf! Hohoho.

I live in a short cul-de-sac. Reversed out of garage, turned steering wheel. Oh ho, that feels a bit light. Drove slowly to road end, applied brakes, instant ABS then complete lock-up. Released brakes and car slid gently sideways into kerb. No forward motion, just the weight of the car and the camber of the road on sheet ice. No damage :)

Drove down street. Same conditions. Got three AYC lights up every time I hit throttle :-D Fortunately, main street had been gritted so some progress made.

Interesting once out in the country, though. Ambling along at around 30mph on very icy road, I could feel the AYC and the diffs constantly moving power around the driven wheels - quite spooky. An element of rear-wheel steering was very noticeable and the car gently yawed along the road. Very safe though and much better experience than any of my friends in non-AWD cars. I wouldn't even have got up some of the hills in a RWD car ;)

Brian

Physician
21-11-2004, 09:53 PM
Very interesting chris_g and H.7 ...... not sure I would dare going out on sheet ice though :sad3:. As I said previously - I can fully understand what you're both saying and will try it next bad weather. After all, it's what I do on wet roads so it shouldn't be too complicated with a bit of testing.

However ..... in a similar vein, let me put a proposition to you about one of the other main systems.

"TCL can be very dangerous" :lipsrseal

My reason for saying this is that a couple of times I have accelerated hard out of a side road, obviously with wheels turned to join the main road, only to find that the car suddenly dies :sad3: as the TCL/ECU cuts the fuel because it doesn't like the speed/acceleration/wheel direction and/or lateral g force.

Comments?

Kenneth
21-11-2004, 11:13 PM
I read an article on AutoSpeed.com about making a little device that hooks up the front /rear wheel speed sensors so that the car thinks that everything is sweet and TCL never activates.

It also had a switch that goes off the brake lights, so when you hit the brakes the TCL comes back on. Hence you dont loose ABS.

I dont know what it would do to the AYC, but it could be fun finding out!

here is the article... its reasonably long, so you might not want to read it at work... ;)

http://www.autospeed.com/A_2199/ERGNTYHJSD_1/cms/article.html