Track Day #1- ZX4 ST @ Willow Springs, CA
Ford Focus ZX4 ST - Track Day 2 - Phil Usher - July
Willow Springs July 8-9, 2006
The Willow Springs International Raceway is a complex with several circuits including a two short ovals, a kart circuit, two road courses and another track which by the looks of it must be designed for Billy goat racing! The feature course however is marketed as the fastest track in the West; most of us simply call it “Big Willow” and it is fast.
Big Willow is only nine turns which makes it pretty easy to learn but no matter how many times I run there I still find it challenging to master. Temperature, wind, moisture, dust, clag (build up of discarded rubber) are variables which continue to produce a new experience each time I enter the track. Couple this variant nature with the high speed and you begin to appreciated what keeps bringing us all back run at Big Willow.
If you're interested here's a link to a video (1,354bps, 40mb 4min) of 2 laps at Big Willow from May 2005
Las Vegas to Willow Springs is approximately 260 miles (I-15 to 58 to Mohave to I-14 and exit at Rosamond). As usual I traveled to the track on Friday afternoon and passed through several patches of rain one of which brought traffic to a complete holt just short of Fort Irvin. Under normal circumstances I would consider 5 mph pathetically slow but the conditions are abnormal in the extreme. The wind driven rain was the pounding my door making it hard to hear the music and I was reminded I of an old joke about Scottish weather; “How do you know when the weather is good in Scotland? Because the rain is falling vertically!” While I wait I call my wife to share the joke with her and she suggests that water may have collected into a pond sized puddle at the bottom of the hill; she was correct (smart lady my wife). As I approached the "pond" memories of prior comments about how the new cold air intake only marginally increases the risk of Hydro Locking caused me to chuckle over the irony: I was now about to perform a real test of my theory. I slowed up to give myself a little room and descended into the puddle maintaining an even throttle and plowed through the water which was deep enough to cascade water over the roof – I emerged on the far side expecting a splutter or a stall but there were no signs of ill effect. Whew!
I arrived at the track and wandered around looking for people I knew and stop when I see a white SVT Focus which had F2Focus and FocalJet decals on-board; I figure I’ll introduce myself. <<Need to add more here>>
Focus performance at the Track: Fears and expectations
· Tires: The tires which proved adequate for Buttonwillow may not be up to the riggers of Big Willow; turn 8,9 & 2 may destroy the left front.
· Suspension: The soft suspension might pogo or be inconsistent through the very high speed turn 8.
Modifications in place on Track Day #2
· Pedals.
· Cosworth Cold Air Intake.
· SCT (Hypnotic) Engine Tune + NRP adjustments.
· Balance shaft delete.
· 142hp (at wheels)
Focus performance at the Track: Results Score Card (points out of 10)
· Engine Power: 5
· Grip/Tires: 4
· Brakes: 8
· Suspension: 5
· Comfort: 9
· Handling/Transitions: 4
· Maintenance: 10
Nothing broke. The Focus was predictable, fun to drive and quick enough to cause some smiles. Engine power, suspension and tires all presented themselves as areas in need of improvement
In more detail
Engine Power
Most people are not accustomed to driving much above 90 mph; turn 8 at Willow Spings is a 4th/5th gear turn at >100mph followed by the very difficult turn 9; Willow Springs is a very scary place for people in their street cars. The result is that many of the faster (or more powerful) cars were not being driven very aggressively through the very high speed turns and the Focus’s lack of power was not as apparent as I expected and it was fun to catch the Ferrari in the turns.
Power increases are already planned for September. Exhaust, cams & oil cooler.
Grip
The Pirelli all-season tires were not up to the challenge of Willow Spings in 105 degree heat. The outside edge of the left front tire melted and showed some signs of minor chunking.
Wheels – On Sunday morning (with the help of Tom Paule) I rotated the tires in an X pattern (front left to rear right) and notice how heavy the stock wheel and tire combination was.
Tires have become problem which must be resolved before my next track session. In looking at the calendar it seems my next track session with the Focus may not be until October so I have some time to work out what I will do.
Brakes
Big Willow is not actually very tough on brakes as the high speed sections help to cool the brakes.
Brakes are not yet a problem.
Suspension
Generally predictable. In the high speed (>100mph) turn 8 the suspension would undulate (slow bounce) which prohibited any attempt to press for higher speed.
I would like to reduce the bouncing. I need to spend some time speaking with suspension experts about what the car does in turn 8 to learn what changes should be made.
Comfort
I remain pleased with the comfort, my bottom stays firmly planted on the seat and thus far I am not finding myself unable to hold my upper body in place either.
I think it will be some time before I find myself in need of a harness or anything else for track comfort.
Handling/Transitions
At Big Willow turn 5 is the most important turn on the track as your exit speed determines your ultimate speed down the back straight and arguably beyond all the way back to turn 2. Turn 5 is tricky; it’s a left hand turn with a downhill right hand turn approach with an uphill exit. I found my speed out of turn 5 was limited by the slow transition from right to left required by the approach. I would come down the hill trying my best to make a straight line for breaking and have to wait for the car to take a set. It’s possible that some of this is tires but to go faster at Big Willow I will need to transition faster in turn 5 and unlike the S’s at Buttonwillow using the curbs is not an option.
Some suspension stiffening for faster transitions is needed. I will start considering choices.
Maintenance
Other than rotating the tires there was no maintenance required at the track. During the return drive home I note a minor shaking in the wheel which I initially attribute to rubber build up from the track. At the track race tires shed rubber which forms into small balls on the outside (offline) of the track. These balls will stick to your tires creating a lump which may take 100 miles or more to wear off. Unfortunately my shaking is not rubber build up, its balance or something else.
The Focus continues to prove itself as a hardy little car requiring very little maintenance.
Conclusion
The Focus continues to be fun and once again I found many who were looking to get a ride; however this time it was mostly my fellow racers who were looking to learn alternate lines through the turns and the focus was a good choice to use for demonstration as it was possible to talk while driving.
Big Willow did prove too much for all season tires and the outside edge of the right left tire showed the signs of overheating.
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