The way the cooling system is designed the coolant keeps flowing after you turn the car off ( till it gets cool enough for the thermostat closes anyway ).

If you come flying into the pits at barbs after being full noise down the hill yea idle it for a bit but if you drive it like most normal people drive down their own street and into their garage the last km or two just turn it straight off. You won't hurt anything.

Besides are you really prepared to leave your baby idling, in nuetral ( I always leave in gear in case the handbrake fails or you forget it ) and walk away. If you do your braver than me.

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Stoner & Webber 2011 World Champions