Tuesday, August 21, 2012

Controlling the launch

The Focus WRC 02 car I drove in 2003 and 2004 did not have the same comprehensive launch control system as the 04 car I drove in 2005. In fact, I never used it on the '02 car. I could press a green button on the steering wheel which revved the engine at the optimal rpm and boost for the start. I still had to operate the clutch, which is the tricky part.

I found gravel is the easiest surface to start on. Rev the engine rather high and dump the clutch. Piece of cake. Tarmac demands more control, you have to feed the clutch gently. Finding the right balance between not burning the clutch and not stalling is the key. Starting on ice and snow is the trickiest. How to do if you are sitting, for example, on the start line of a Swedish stage, on fresh ice and snow? You can't rev it up and dump the clutch. You'll just find yourself wheelspinning, going nowhere... Feeding it tarmac style won't do it quite either. The secret is to get the car to roll a little bit forward, being careful not to stall, and then dump the clutch gently. Sometimes you'll see drivers dump the clutch brutally on icy stage starts. They can do that when there has been many cars starting on the same place and the ground is dug up to the gravel.

 '02 Focus WRC
In 2004 Rally Monte Carlo the Ford head engineer chatted with me just after shakedown. He said he had been sitting on the start line and timed my start against Markko Märtin's. We had exactly the same time and he said that was a good start. We had coldish tires on damp tarmac and the start led up the hill perhaps a hundred meters until a sharp right, out of the town of Sospel. Markko  was using launch on his '03 spec car, I wasn't. I had a good start there but it wasn't always the case, in fact many times I was unhappy with my starts. From the '03 spec car onwards and including the '04 spec I drove in 2005, launches became a breeze. Here's why:


No matter what, it is always perfect. The result of a very expensive high tech transmission.

Here's what happens in the car:

Once I arrive at the stage start the marshal calls me to the start line if it's free. At this point, on gravel or snow, if I see ruts I'll settle the car in them. That's where grip is best for the launch, unless I think they're too deep for the car. This happens a lot if you run way down the order or on the second pass, at which point the start line often looks like a potato field anyway. 

Once I am nested in, I give a last tightening on my belts, check if all the stuff I need is on, etc. 

I then ask my codriver to read the first 3 or 4 corners out loud so I can visualize my stage beginning and let it flow onwards.

When 10 seconds remain I hit the "STAGE" button which you learned about in my previous post: RSI : Water injection.

Immediately after I push the clutch pedal and engage 1st gear.....clank.

I pull the handbrake, at this point the engine revs up automatically to the optimal amount of rpm preset in the program.

I let go the clutch pedal and the car holds in place...Did I mention the car is equipped with a  hydraulically controlled clutch?

I push the throttle to maximum but the revs remain as before...the boost kicks in.

5,4,3,2,1... I let go the handbrake and the car goes, like magic, every time. A perfect start.

All I have to do then is shift into 2nd gear and drive the stage normally.

If for some reason the computer detects a malfunction during the launch sequence a warning message flashes on the display. All I have to do in that case is keep control over the clutch and launch manually.

'04 Focus WRC
I might have mentionned it before but that magic clutch also kicks in automatically when you spin out, just to keep that engine running for ya. It's there just in case you don't get the reflex to push the pedal in time... A good time saver considering the engine can be a bit long to restart when very hot just after an in-stage stall.

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