USAC Sprint Car test - Oval racing?!

Through my good friend Bruce Ashmore, a world-class racecar designer/engineer currently working out of Indianapolis, I had the good fortune of getting introduced to Ken Pierson.

Ken has been racing on ovals as a team owner for over 30 years and has - wait for it - 139 main event victories and 5 championships. One of the cars he races is a USAC Sprint Car. This car boasts an enormous V8 engine generating 750hp and weighs in at only 550kg (1300lbs). The end-result? Acceleration that is FASTER than Formula One! The rear tires are just ridiculously wide in an attempt to maximize traction. More on that attempt later....

Here's how they look when they fly by -





I have never before driven on an oval, with the closest thing being the Motegi exhibition race in an N1 endurance Nissan 350Z set-up for road-racing. This fun event took place on the Motegi oval, with chicanes built in at the end of each straight, and in the RAIN...

So I prepared as well as I could, talking to drivers and engineers with experience with this kind of car.

All in all, I got about 50-60 laps on the 1/4 mile oval - where one lap is 12~13 seconds. Driving this monster is something else. I have never experienced the rush of acceleration that this car can deliver.

The sound is a little off in the video unfortunately.



Let me first describe the machine.
No clutch or flywheel, one-speed transmission, solid-rear-axle (no differential), staggered left and right tires, seating position is very upright with the driver almost on top of the steering wheel that is closer to being parallel to the ground than at the usual 90-degrees in road course cars.

The end result? Absolutely the biggest rush I have ever felt! Each straight was probably just a little over 100 yards, since the entire oval was only 1/4 mile. But, the due to the power delivery of this engine, there is no point on the track where you could actually put all of that torque down without lighting up the tires - including at the end of the straight going around 100mph.
Think about it - coming out of the corner, concrete everywhere, adding in the throttle and the car just bolts forward, jerking you back, but you can only continue to add throttle at a pace to where even after going around 100mph, the car is still traction limited. I've definitely spun those rear tires plenty of times in an attempt to inch toward that 100% throttle. NOT POSSIBLE on a track this short!

My thanks go to Scott Pierovich and Kevin Urton for helping me understand the car and how to drive it. Scott raced in the Sprint Car that weekend and finished in 3rd place on the podium. Kevin, now retired, boasts an incredible career of having won over 100 races both of asphalt and dirt.

Here's a video of the Saturday night rolling start for the USAC Sprint Car race:


I continued to get faster every session I went out as I got more comfortable with the car, and now I cannot wait to get in it again! I've had a chance to think over all of the dynamics of the car.
One of the biggest things that did not click initially - the left-right stagger. The fact that the circumference of the tires is smaller on the left side of course means that the neutral state of the car is turning left, not going straight. This makes the cornering easier, but the disconnect I had was how that affects the available traction - both for braking and acceleration. Normally, in a car that is symmetrical, maximum brake/acceleration traction is available when the car is pointing straight with no steering input. In a staggered car however, the car's neutral state with maximum longitudinal traction is actually when the car is turning at that exact angle when the steering wheel is straight - which occurs twice during the corner - as the steering wheel is released from essentially turning right during the straight, and then when it is getting unwound but the car is still turning at the exit.
I was just throwing the car into the corner to where I was not losing any time at the entry and the middle, but I was still down by several hundred engine revs compared to Scott at the end of each straight - because of my conservative initial throttle application while the car is still turning, coming out of the corner. THAT is when the car has maximum traction for acceleration! Well.. that and I did not want to stick Ken's car into the wall on my first-ever drive on an oval. Probably would have left a sour taste for everyone.



I am hoping that next up is another test in the Sprint Car, with Ken's blessings, at Irwindale 1/2 mile track in November.

Where is all of this going? Ken Pierson and Bruce Ashmore are involved with the Silver Crown series and the next-generation Gold Crown - a new series slated to debut in 2011. The Silver Crown car is very similar to the Sprint Car, but with an extended wheelbase to accommodate a larger fuel tank for longer races, and another 100hp, just for kicks.

I have had the most fun pressing on the throttle in this monster and just waiting for it launch off into space at every straight. Thank you Ken!
Ovals - here I come.

Visit Bos Sheet Metal for any A/C and heating needs in the Sacramento area!

Visit Ashmore Design for information on Bruce Ashmore and the Gold Crown Series.

FCJ Season Finale - Rd. 13/14 at Sugo

On September 26/27 weekend, we had the final two races for the 2009 season in FCJ.
Sugo is a high-speed, high-guts track where one must pair aggressiveness with smoothness, and sometimes the end-result is being in the wall - very little run-off and a lot of uneven places on the surface with varying degrees of grip.

The three days brought about fantastic excitement.

On Friday practice, we had three sessions of one hour each. Seeing how this was the very last practice, we figured to do a little experiment that would otherwise be frowned upon.
Since I am 10 kg (22 lbs) overweight with the FCJ Series rules, I figured it'd be good to run without the handicap by taking out the fuel to see what happens. The conditions were good for the experiment since I could eliminate tires and track variables by comparing the time differentials and data in acceleration/braking forces over two sessions - one session full tank and then the second session with less fuel.


We were able to take out 7 kg of fuel (15 lbs) for the final third session. With all things being equal, I was over 0.5 seconds faster.
The car was so alive - the rear felt so much more fluid and responsive to all of my inputs, and it was a blast to drive. Of course nothing can be done with this info, but I figured it's good to have - 22 lbs is probably around 7/10ths of a second at this track. We run 1:22:xx lap times since it's pretty short.

For qualifying, I got 13th for Q1 and 12th for Q2. The 0.7 second weight handicap would have placed me in 2nd position for both sessions.


The race in the afternoon got off to a good start - I passed 4 cars by the entry to turn 4... as I got on my brakes, I caught a car still accelerating in the back in my left-side mirror, after that instant, I had to get back to being busy dealing with the cars next to- and around- me. Then I braced myself, knowing the car in the back could very well hit me.
Sure enough, I felt a little hit from behind, and then the next moment was stunning - I saw a car pass right to the left of me at my height and continue to fly above diagonally over my car. I saw the entire bottom of #11 car from the front to the rear as it continued to climb up beyond my car. My car was still drivable but I just parked it, knowing there was nothing to gain but possibly only more things to break.







The tire marks that the #11 car left me by its right-front were about 4-5 inches away from my helmet on top of the left side of my cockpit. CRAZY.

Looking at the data, the driver of #11 got a bit too eager, and he broke later than is normally possible for that corner, but to add to that, on cold tires, and worse of all, on the very inside line on the left of the track where nobody ever drives, guaranteeing layers of dust and sand. Combine all that, and he ended up with a 25mph speed difference at the instant of hitting my car from the left rear.

On the Sunday race, I was starting 12th on the grid.
I got off to a good start from the line and got past three cars, getting to 8th position on the first lap. The entire duration of the ~40 minute race after that was rather uneventful as the car in front was not close enough for me to challenge and the car behind me was in the same kind of position relatively to me. The Sugo track is so narrow that, in reality, the only places for passing are braking into turns 1/2 and the back-straight.
I finished 8th. I made two small errors in turns 1 and 3 over the duration of the race where I lost a few tenths, but overall it was a good, solid race.



Visit the FCJ Media Gallery for Rd 13/14 at Sugo.

I want to sincerely thank everyone that has helped me this year - all of our series sponsors, and my personal sponsors - Avanzza and Bomex.