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Track Analysis: Summit Point, Jefferson Circuit Extension


Last weekend I had the chance to drive and instruct on the extended Jefferson Circuit at Summit Point. Below is my analysis of the changes and a description of my line around the track. This works for me in a FWD MINI on summer street tires. Your results may vary. No wagering. (In-car video by ReplayXD.)

Jefferson Circuit Extension
The extension (turns 4 – 10) adds about a half a mile to the old track and doubles the number of corners. I think most old-timers would have preferred if they had just renumbered the new section as corners 4a to 4g instead of renumbering all of the corners, but we’ll use the new numbering scheme. The old track could be run in both directions. The new layout only works in a counter-clockwise direction (though you can still use the old course in the other direction.)

Google Earth hasn’t yet uploaded a new image of the circuit so the plot shows the path through open fields, but it is actually paved, just not well (more on that in a minute.) How to read this chart: Turn numbers are in circles. The color on the path of the car shows acceleration (green) or deceleration (red). Note that deceleration might just be lifting as in between 2 and 3 or the apex of 4 or 8. Green speed readings on the track show max speed before deceleration and red shows apex speed. The bars in each corner show relative lateral G load. Green bars are .4 to .8 Gs. Yellow bars are .8 to 1.1 Gs. Notice the lateral load where the new track rejoins the old track and in the middle of the back straight. There the car is going straight and the lateral load is from the unevenness of the surface. You see some of that on the front straight from 14 to 1 as you drive across the crown to set up for turn 1. Red arrows show apex visuals. If you already know the old Jeff, then jump down to Turn 4.

entry to turn 1
When you enter the track from pit-out, stay to the right all of the way to the apex of turn 1, otherwise, when at speed cross-over from right to left on the front straight and look down the track to the flagger’s bucket. RWD cars set up to the left for turn-in. The road is crowned so FWD will want to be more in the middle of the left half of the track or you’ll never get over the crown to the apex.

turn 1 apex
The apex is very late and almost at the end of the curbing. You can ride the middle part of the curbing, but stay off of the end as it will unsettle the car. Stay to the right upon exit and let the car settle before turning-in to turn 2.

apex turn 2
Turn 2 and 3 should flow. If you’re early for 2, you’ll also be early for 3 so wait to turn in and make 2 a very late apex. Lift or tap the brakes to turn-in to 3.

apex turn 3
Turn 3 is one of the few corners where you can ride up on the curbs without unsettling the car. Apex is very late and carry as much speed as you can. Don’t worry about track position on track-out as the entry to the next corner is rough and you’ll probably have to lift anyway to get back to the apex.

apex turn 4
Turn 4 is also a late apex. Ride the rumble strips and try to straighten 4 and 5 as much as possible.

apex turn 5
The exit to turn 5 is the roughest spot on the track. Point the car straight after the apex and brake in a straight line. Wait for the second bump before turning-in to turn 6.

apex turn 6
Set the car about a car-width from the curbing and late-apex turn 6 at the top of the hill. Open the wheel and let the car track out to set up for turn 7.

apex turn 7
Turn 7 is the most difficult corner on the track. You must be patient, especially when your tires are cold. It is a decreasing radius corner. Look for the path of the patch. Set your entry squarely in the middle of the patch and then pinch-off the apex. Trail-braking helps. If you don’t sufficiently load the front-end, expect to under-steer through the apex and off the other side of the track. Track out to mid-track.

apex turn 8
Treat turns 8 and 9 as one double-apex corner. Do not track too far out in the middle as the pavement drop off is pretty severe.

apex turn 9
Ride the curbing on curves 8, 9, and 10.

apex turn 10
Late apex 10 but get on the power early to increase the length of the straight. The point where the new track joins the old is quite bumpy so stay away from the track edge.

apex turn 11
Stay 3 feed from the edge in the braking zone to 11 to avoid more bumps. Turn 11 will really hook up when done right. Release the brakes as soon as the car starts to turn-in and power through the exit using the full track width. Cross over from right to left to set up 12.

entry to turn 12
Staying as far left as possible, turn in for 12 as soon as 12 and 13 line up and straight-line 12.

apex turn 13
Stay off of the curbing on 12 as it will really unsettle the car. Downshift and brake for 13 in a straight line. Some people are able to carry enough speed to brake once through 13 to set up turn 14. In the FWD MINI I have to release the brakes in 13 to get the car to rotate and can actually accelerate a little up the hill before turning-in for 14.

entry to turn 14
RWD set up 14 by going as deep as possible for the entry. FWD don’t go too deep or you won’t be able to cross the crown to get back to the apex of 14.

apex turn 14
The apex of 14 is very late. Stay off of the curbing. If you are tracking out to the edge of the track before the pit-in lane, then your apex was early. Cross over from right to left and do it all again.

Larger photos here.

Jefferson Circuit at Summit Point

For me, this brings to a close my motorsports activities for 2006. On the weekend of November 11th, I attended my fourth BMW driver’s school. This school was on the Jefferson Circuit at Summit Point, the same place as my first event of the year. Saturday was a beautiful Fall day, but Sunday was just plain nasty. Wind and rain all day, making for a slippery track. Slippery is actually good for a MINI driver (any front wheel drive car for that matter). On Saturday in the dry I was probably about mid-pack for my run group, but on Sunday on the slippery stuff MINI lead the way. (Yes, this is not a competition. It’s about skill. No wagering….)

The day got off to a rather rocky start when my instructor put his E36 M3 into a tree on turn 5. He had almost completed a 180 degree spin on the track when he just ran out of track. We only slid 50 or 60 feet but it seemed to take forever. We came to rest in about a foot of water up against some trees. He had a pretty large dent in the left rear quarter panel. Once we pulled it out a bit it was drivable but his day was pretty well shot. To get out of the car, we had to take off socks and shoes and wade through the water. Not so much fun when it’s about 45 degrees outside.

In the end I think it was a very instructive day, however. The conditions were such that you were on the edge of losing control at very low speeds so you learned quickly to respond to what you car was doing. I’m already looking forward to picking up in the Spring.

Tighten the Nut Behind the Wheel

There’s an old saying in Motorsports that if you want to go faster, you should start by tightening the nut behind the wheel. It’s easy to blow a big chunk of cash on go-fast goodies for your car, but if you can’t find the line through a curve or you just aren’t smooth, you’ll never be fast.

I’ve recently taken up Autocross. Although I’m waaaaaay at the back of the pack (and unfortunately classified in the mod-till-you-drop Street Mod class) I’m having a blast. It started with a desire to improve my general driving skills. The more time I spend on the freeways around Washington DC, the more I’m convinced most of my fellow drivers are morons. One in four seems to have a cellphone surgically attached to their head. Of the remaining three, two are tail-gaiting each other at 85 MPH in SUVs with under-inflated tires.

Figuring a good offense is the best defense, I started to think about my own driving skills and my ability to avoid bad situations. In the asphalt jungle of “fight or flight” the MINI driver’s only defense is flight. It started with a highway safety course at the Jefferson Circuit at Summit Point put on by the local BMW club. That was followed by a high performance driver’s course on the same circuit.

This past weekend, I attended another driver’s school on the Shenandoah circuit. Now I’m hooked. These are not racing schools. There’s no wheel-to-wheel competition. It’s all about control and knowing your (and your car’s) limits. I hope the skills I’m improving on the track will improve my autocross skills as well.