Fast Lap With Billy Johnson -Buttonwillow Configuration #13 CW


Turn 6 (Grapevine)

It is important to get down to the apex of this corner.  If you are having trouble getting down to the apex, turn in earlier.  The curbing can help rotate the most understeering of cars and I’ve come to like using it to make the corner a bigger radius with an earlier turn-in.  Be careful not to turn in too aggressively because this is a pretty quick corner and spins do happen here so smooth inputs are recommended.

Turn 7 (Club Corner)

While this is a pretty fast kink and smooth inputs are needed, quicker hands at turn-in can help the car to achieve and earlier ‘set’.  By getting the weight of the car on the left early at turn-in, the car will be more comfortable to drive though the corner.  I don’t like using more than half of the apex curbing because it upsets the car and can cause the car to ‘skip’ to the left side of the road.

Turn 8, 9 (Bus-Stop)

Exiting Club Corner, stay in the middle of the road setting up for the next bend to the left, Turn 8.  This is a high speed transition that tests the stability and suspension of the car.  Apex the corner where the light grey concrete patch/apex curbing is.  Make sure to have the car back under control and straight to set up for the Turn 9 Bus-Stop. 

I don’t like hitting the curb on the right entering the bus-stop because it upsets the car on the side you are about to load.  Brake in a straight line (the amount of braking will be dictated by how much speed you are carrying into it) and release the brakes and add a little throttle at turn-in.  Turning-in on throttle will make the front of the car light, inducing a stable and comfortable understeer, which will allow the car to be more compliant over the apex curbing.  Use the entire curb where your left tires are almost in the dirt.  Once the car ‘lands’ and is stable, squeeze to full throttle and track-out.  If you are having problems getting back to power or are pinching off the exit, turn in later.

Turn 10 (Truck Stop)

Exiting the Bus-stop, get back over to the middle of the track to set up for the Truck Stop.  Turn-in from the middle of the road, apex, then track out to the left.  This corner can be flat in many cars and at worst is a brief lift off the throttle.

Turn 11 (Riverside)

The fastest corner on the track, Riverside has a slight on-camber to it and is a slightly decreasing-radius corner (tightens up).  In cars with a lot of aero and grip like the NSX on racing slicks, it is possible to hold a tighter line, but for most cars it is faster to exercise patience and stay mid-track until you can see the apex curbing ¾ the way through the corner.  Once you can see the apex curbing, tighten the line to get down to the apex curbing, but don’t use the curb itself. 

The key to this corner is mid-corner speed.  It may feel faster to hustle the car in to the corner with a lot of entry speed, but the time lost from being off throttle mid-corner to exit and not being able to get back to power more than offsets the high entry speed.

It is important to have some maintenance throttle the entire time through the corner and minimize any time off-throttle.  Lifting off the throttle causes engine-braking that slows the car down significantly at these speeds and worse with higher RPMs.  Ideally, the lowest cornering speed should be the point where you see the apex curbing, then tighten the line and go to full throttle.

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