I was at Thunderhuill yesterday driving the new five mile configuration. I haven't found any description of how to drive the West course, so I decided to write my own. [For those unfamiliar with Thunderhill, its owned by the San Francisco Region of the SCCA, it recently had an expansion to add the West portion.] Here's their track map:



Video of one of my attempts (in the JCW): http://btwyx.com/Movies/THillSept14WBest.mov

Comments? Critiques? Suggestions?

Run the track as normal until you track out at turn 8. As you go up the hill to 9, move over to the left of the track (instead of staying right). When you get to 9C (the connector to the new bit at turn 9), brake change down to third, and take a sharp right up the connector, aim to stay to the right of the track. You’re now going steeply uphill to a blind crest. Beware, the track goes to the left (do not barrel full tilt over the crest). When you can see there’s an apex to the left, aim for it, if you get the angle right you should be able to touch the apex on your left, then see there’s an apex on the right which you can also touch. Various aiming points in the distance have been proposed, I favor imagining you can see the track and aiming for that.

Once you hit the second apex, there is another blind crest, you are pointing in the right direction, you can barrel full tilt over the crest if you’re brave enough. Once you can see the track, the track falls steeply downhill down the valley (about 100ft down in 1400ft of track). There is a shallow apex to your left and a kink to the right (2W) further down followed by a longish straight (to 3W). I keep to the left at the shallow apex, and change up to 4th, the hill is pulling you strongly down at this point.

I’m still not too sure what to do about 2W, it looks like a simple kink you can take flat out, but the camber changes suddenly to off camber. It is on camber if you’re coming around 2W from 1W. The change in camber tends to throw you off the left of the track if you’re too incautious and take it too flat.

Then its on down the hill to 3W, I’m running out of revs in 4th by the time I get there. I don’t think a change to 5th would help. 3W is marked by a sharp concrete triangle at the apex. Brake, and drive straight over the triangle. You should aim to connect the triangle and the apex of the kink following 3W.

This brings you to 4W. I’m still none to sure about this. Like many corners, 4W is blind, you can't see the exit when you enter. When I took what looks like the obvious line, I found myself driving straight off the track. Stay right, and approach from the right. I was having reasonable success with carrying on the line from the 3W triangle past the kink to the outside of 4W. Brake and aim to connect the apex of 4W, with the apex of the kink on the outside of 4W with the ouside of the entry to 5W, you can see once you get to that apex.

Get to the left of track to enter 5W, as a pretty standard right hander, except its also blind, the hill on your right obscures the exit until you arrive. The exit of 5W is the esses. Aim to flattened out the essex and drive as straight as possible through the first few kinks. You’re still going slightly downhill, so speed increases faster than you’d expect. I was changing to 4th in the middle of the middle kink. The exit of the esses is a more substantial right hander, which is not named. After the unnamed right hander move to the right of the track to set yourself up for 6W.

6W is a blind off camber left hand sweeper. It looks like its more of a corner than it is. As you can’t see the exit, your self preservation instinct thinks you should follow the road around to the left. If you can over come your self preservation instincts you drive off the right of the track over the blind crest. If you get it right you find there is an apex there you can drive straight past the apex of to get to 7w.

For 7W I carried on the line I’d got past the nameless apex at 6W exit and am aiming to run off the track, before you do run out of track, brake, change down to 2nd and take a very late apex around the hairpin. Power out of the hairpin, changing up to third and hurtle towards the blind crest which is 8W.

8W is a blind left uphill right hander. Its a lot faster than your self preservation instincts will allow you to go. Its really not very sharp if you look at the map, it looks a lot sharper when you can’t see it. You should be able to take it with a slight brake and an early apex. I never got to test this theory. Track out to the left to set yourself up for 9W.

9W is a sharp, almost hairpin, right hander, apart form being sharp, its not particularly difficult and for once you can see what’s happening. For us there was a pool of mud at the apex of the nameless kink on the exit of 9W, which made 9W even sharper. Steer round the apex and/or pool of mud and head for 10W.

10W is another almost hairpin, it leads onto the “long” straight, so its important to exit with as much speed as possible. A late apex is the obvious way to go. As there is a lot of run off area before you hit the pit wall you can take an earlier apex and use some of the available extra space. If you run into the pit wall, you’ve over done it. The straight is actually slightly uphill, so you don’t gain as much speed as you expect, I was still managing to get into 4th at the end of the straight.

This gets you to 1W. 1W is a 180 degree sharp right hand multi apex sweeper, its entered past a nameless left hand kink. At the end of the straight, brake take 3rd, and aim for the nameless kink, aim to hit the nameless apex and the first apex of 1W, then shoot straight towards the outside of the track. Before you run off the track, brake and sweep right around all the apices. You don’t need to get close to any apex except the second last one. Once you get there aim to shoot the gap between the last apex and the nameless left hand apex into the 10C connector.

The 10C connector is a straight which goes up and over a blind crest. There is road to land on over there, so you can go full tilt. However, you have to brake to make 10C to get back onto the main track. I never did work out where to brake, a lot like turn 7 at Laguna, if you brake before the crest you feel like you’re just crawling over the crest. if you brake once you’re past the crest you may overshoot. The track is falling sharply away from you so you may not be able to brake as fast as you expect. You do have some room to overshoot, the width of the main track. The crest is about 30 feet up and 30 feet down in only about 100ft of track. Once you’ve braked, its a pretty standard right hander to join the track for turn 10. You do have to track out to the left for 10C and immediately come to the right for 10E, but at least you’re not going too fast.

 

Nice write up! I have never been so I can't comment on the accuracy. However I am picking up my '15 JCW coupe so I would like to join you at a local track at some point. I'm an A group driver so perhaps you would be willing to coach? I had one of the best coaching sessions in the past when a guy who had the same type of car I had coached me. It makes a huge difference.


Edit: Good video too. Looks smooth.