lol, hard to do at thunderhill, its a 3 mile track, so its a 45 minute walk!

 

I've done this on the kart track at Sonoma (Infineon) and it was very helpful. I would recommend doing this when you have the opportunity, even if it is just over a couple of corners. But yes, not so easy to do for a track the length of Thunderhill, especially on an HPDE day when there's no time during the day when the track is cold and the conditions are changing by the minute (storms and sunshine rapidly wetting and drying the track).

 

yeah the Kart track is hilarious in the rain, that does need a rain line!

when i'm bored i'll poke the tire temp into the track, and thunderhill will start in the morning @50-60F and be 130F or so by about 1pm, although it depends. its a big swing!

on an HPDE day i don't think you'd see this, but racing on a sunny dry day (the other 364), the track is fastest when the air is still cool, but the track has warmed up a little from the sun, usually 10-11am. before that the track is too cold, after that the air is too warm.

 

something interesting is to mount the video camera low in the rear of the car. then listen how the rear tires react to the different surface types you encounter on the track. Same thing in the rain--its a different surface.

 

Thunderhill is the easiest to walk. Go out at dusk, the gates are all open and you don't need to be supervised.

Laguna is the worst. You need to be escorted all the way round.

 

Thats one of the differances between a good driver and a great driver.

A great driver knows every little thing about the track, bumps, tarmac, where its more slippery when its wet etc.

Heres a photo from this years 24h "Winterhell" at track Mantorp Park in the beginning of march. My team was up early and walked the track and disucced lines, ice, snow where the water will start flow then (if) the sun starts to shine etc.

We finished 1st and 13 with our two cars.