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Discussion Starter #1
BMW club is holding a DECA day (at Shepparton) on the 13th of March (Sunday). I'll be going to that one so I'm wondering who else is interested? This day will be billed as 'driver training' and the morning is devoted to some basic driver training excercises. After that it gets to be a bit more freeform with time-trialed cone-dodging exercises.

The entry forms are not available just yet, but I thought I'd pop this up here nice and early as once the forms are released, it'll probably get filled in pretty quickly. These events accept only about 40 - 45 entrants and cost around $50. There are no real requirements for DECA events ie. no helmet, no extinguisher and no special licence is required. One just needs a road-registered car and that's about it.

So anyone interested? If there's any interest then I'll post the form (or link to it) here as soon as it available.
 

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Yeah, why not, this time i will interest. But where is shepparton? is it far from Melbourne?
 

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Discussion Starter #3
But where is shepparton?

It's off Hume Hwy in the direction of Sydney. Often people take the 'scenic' tour on the way back as there are some fine stretches of road there (ie. Black Spur).

is it far from Melbourne?

About 1 hour and 45 minutes from the city (that is at legal speeds).
 

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Discussion Starter #5
The entry form for the DECA day on the 13th of March has been released. It's a little bit more than expected (ie. $90), but you don't need anything else. There is only 30 places so don't take too long as the places will probably go pretty quick.

Get the entry form here:
Entry form (under DECA Driver training)
 

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Discussion Starter #6
The DECA day is less than 2 weeks away. I'm wondering if I'm going to see there anyone from here?
 

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Discussion Starter #8
when is the next one?

Hmmm .... not for a while. There may be one held by HSV club on June 12th, and then there's probably a couple more in November/December.
 

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Discussion Starter #11
After watching the doughnuts in the 2nd clip, remind me never to lend you my car!

lol :) The CV8-R was not an easy car to control while it was sliding. It was very hard to get the back to brake loose (as it's natural tendency was to understeer), and then once it starts spinning it wes hard to stop it from doing so. That's what you see in the 2nd clip. I did get it spinning, but could not stop the spin at the right time. The idea was to get out of the spin 1st time round, but by the time that happeed I was facing totally the wrong way. So I completed the 2nd spin, and again I did not manage to stop the car from spinning in time (ie. I overshot my 'exit point').

Though, later on in the day we had this giant circle taking up all of the skid-pan, and I maned to get the car to execute this beutifull 4-wheel-drift for a good 1/4 of the arc. Shame I don't have it on tape.

ps.
If you're going to do doughnuts, then the skid-pan at DECA is the best place to do it ... it's very smooth and un-abrasive surface so you can hardly see any wear on the tyres after a day there. Next time I'll bring the Zed again.

pps.
Here's another short clip. This time it's an MX5-SE doing a pretty good job of it (until the last cone):

MX5 SE
 

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It's nice to practice on the V8 car, because the massive torque can be hard to control or easly to lose control :) how come u didn't use your Z? :)
 

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Discussion Starter #13
It's nice to practice on the V8 car, because the massive torque can be hard to control or easly to lose control

You'd be surprised, but the Zed has more torque and power when you take the weight into account. The Zed seems to have a power/turque advantage everywhere, and on top of that this CV8-R is an automatic.

Main difficulty I found with the CV8-R was the combination of weight, relatively soft suspension and lack of torque/power at lower revs. It kind of felt like everything happened a second after you thought it would and therefore I found it hard to give the car the right inputs.

On the other hand the HSV R8 is a real torque/power monster. That car has no problem spinning the rear wheels at any revs.

how come u didn't use your Z?

We had 2 cars up already already so I thgat thought bring the Zed up as well would be an overkill. Also I wanted to put the CV8-R through its paces as until then I've only driven it on the road.
 

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David - what's with the puddles of water on the track??? Had it been raining previously and the sun dried up the even surfaces but left small puddles elsewhere? Or was the skid pan wet from a previous event and had only half dried up? Or did the organisers just try to make the day more interesting by having a few puddles about the place to vary grip levels?
 

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Discussion Starter #15
David - what's with the puddles of water on the track???

There are sprinkers on the skid-pan and they used them to wet about 1/3rd of it. Though, with the sun and temperatures that day the water dried up pretty quickly ... and hance the 'puddles'.

So you're right on both accounts - it was drying up, and it did make it interesting in terms of varying grip levels.

One of the interesting things that you learn at DECA is that the car does not 'spin out' when you enter the wet area ... at most it understeers instead. Though, when you leave the wet area, and enter the dry area, that is when the car wants to spin. You can see every car there do it and a lot of them actually spin once they're on the dry. A lot less people spin on the wet.
 

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[/quote]

Can you explain why the car wants to spin when it hits the dry stuff - seems to defy the laws of physics????????
 

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Discussion Starter #17
Can you explain why the car wants to spin when it hits the dry stuff - seems to defy the laws of physics????????

It does go against what you would initialy think ... surprised me as well the 1st time, but it is always the same each time I go. This 'odd' behaviour makes sence when you break it down to what is as you transition top a different grip surface. Keep in mind that they often have this excercise set up as a big circle and 1/2 of it is wet ... you go around it a couple of times in a single run. When you look at what's happening this is how it goes:

Going from dry to wet:
While you're on dry, the the car is within grip limits (ie. neither front or back is sliding) as you're trying to keep it just under the threashold of grip. Now when you enter the wet area, your front wheels will hit it first. Now your front wheels are in the wet area, and your rear wheels are in the dry area which means that there's less grip for your front tyrtes than the rears. If you had too much speed at this time (for the wet surface) then the front will strart sliding (ie. undresteering). Once the car is understeering then it cannot oversteer even when the rear wheels hit the wet area so you just keep on understeering. That is unless you really provoke it with throttle and break the rear traction that way.

It's quiete interesting to actually fly into the wet area with extra speed and know that there won't be enough grip. You'll notcie that it does not makker how quick you fly into it, it will always undertseer on entry.

Going from wet to dry:
Now when you're leaving the wet area the things will reverse ... not only will your rear tyres be on the wet (ie. slipery) surface and your front tyres on the dry (ie. more grip) which in itself can cause the back to slide out of you had enough speed. Though, what really kicks the back out is the fact that if you were on the limit (or close to it) in the wet then you probably had a fraction extra turn-in lock on the front wheels to combat some mild understeer. Though, when these front tyres hit the dry surface then they now have more grip and what will happen is that your front wheels will no longer understeer, but instead will follow the line that you have dialed with the steering wheel (ie. tighter line). Your rear is still in the wet and hence does not have any extra grip and therefore will more than likely swing out pretty wildly. You see almost every car do that and what you learn to do is ease up on the steering-lock when you're about to get onto dry in order to keep the car straight (ie. select a wider line) .

I hope that makes sense.
 

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Now its clear as daylight. Thanks for the thorough explanation David - I feel silly that I did not think of grip altering processes after you made it sound so simple.
 
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