Camaro vs. Mustang at Autocross

Disclaimer: I have no financial interest in the success or failure of General Motors, Ford, or Miller Motorsports Park.

First question: How does a Camaro wind up running at a Mustang club autocross? The Porsche club http://int.pca.org has graciously invited the Mustang club http://www.numoa.com to join them in autocross for years. When the Mustang club held its own first ever autocross, they not only graciously invited the Porsche club to join them, but said "everyone invited." By virtue of owning an old Porsche that does not run (yet!) I am a member of the Porsche club, so that is how I heard about the Mustang autocross. What really cinched the deal for me was the race track, Miller Motorsports

Park http://www.millermotorsportspark.com would rent a racing Mustang for $30! At first I was totally elated -- heck, I probably do more than $30 of tire wear on my own car at an autocross! Then that sinking feeling hit me -- it was probably $30 per lap. That was OK, instead of doing 20 or 30 runs in the rented racing Mustang, I'd do just 2 laps. Also, renting a Miller Mustang runs from $300 for a learning session to as much as $2400/day, so $30 really was quite a bargain. I asked if it was OK if I ran my daily driver Camaro for my other laps, and the Mustang club graciously said it was fine. The photo is an old one. For some reason the Mustang club did not post a bunch of pictures of my Camaro.  :)

Maybe 15 Mustangs, 2 or 3 Cobra kit cars, and a pure racing  Mustang showed, plus my Camaro and a Porsche 944 representing the Porsche club. I did about 10 laps to learn the course really well before my Mustang runs.

First, a few words on my Camaro. It is prepped to the maximum allowed by SCCA Solo F-stock rules. It has racing shocks, a huge front swaybar, racing tires, and a cat-back exhaust. I was turning some pretty good times. Some credit goes to 40 or 50 autocross days of experience, but much of the credit goes to having race tires on the car -- I was probably the only daily driver car there with race tires.

Some proof the huge difference race tires can make: A friend and I compared once -- same drivers, same cars, same day, just tire swaps. I ran race tires in the morning, and street tires in the afternoon, and vice versa for my friend. On a 60 second course at a pretty slippery venue, he was 4 seconds faster, and I was 5 seconds faster, on race tires vs. street tires! Another time I corded my race tires and finished my day on street tires. I was about 2 seconds faster on the race tires, this time at a very grippy venue and with good BFG KD street tires.

Now for the rented Mustang: Here is a link describing it: Miller Mustang. It is about an SCCA Solo ESP level of prep. It was pretty similar in prep and capability to my car, but it had about 25 more horsepower, lowering springs, and street tires. You can buy this car for $46,000. Miller also offers a version that has 300 fewer pounds (stripped interior), aero aids, telemetry, and race tires, and I imagine other goodies, for $75,000, the "FR500S." Photo credit: http://www.numoa.com , this pic was taken the day I drove, but I'm not sure is that is me or Adam driving. Note how flat the cornering is.

Here is a bench racing comparison:

The bench racing analysis is the Camaro should be faster due to its tires. Given race tires, instead of its street tires, the Mustang should be faster.

I signed my life away to drive the Mustang. I was liable for damage to the Mustang, even if not my fault, not to exceed $46,000. Since autocross is just one car at a time, I wasn't worried about car-to-car contact.

Now I get to strap in. Since the Mustang has no sunroof or T-tops, I fear I won't be able to get my helmet on once strapped in, so I put on my helmet first. First surprise: The Mustang has a full interior, I had assumed it would have a stripped interior. Second surprise, the seat goes back so far I can't push the clutch in all the way! As a tall guy, this is the first car where I have ever had that much leg room. It is nice the full cage doesn't restrict the seat travel or headroom. Adam, the MMP guy in charge of the Mustangs, helps me strap into the four point harness. I turn the key. Doh! The motor is already running! Luckily the electronics intelligently do not engage the starter, just the tach needle goes to zero for a moment. The motor was so smooth and quiet (with race track noises and my helmet on, anyways), I didn't know it was running. The shifter has short throws and a very nice, direct feel. Unlike the Camaro, I can see some of the hood. Photo credit: http://www.numoa.com .

Finally I get my turn. I launch. My brain dyno says the Mustang isn't accelerating as fast as my Camaro. Due to the low gearing, it rapidly runs out of rpm and I hit the rev limited right away. Now for my first real turn. It seems to me the Mustang is softer and leans more. At the Southwest hairpin, I try to drop it into first -- force of habit from my first 10 runs -- and the car grinds. Oh yeah, there is that sign in big letters on the dash that says to not use first gear unless the car is stopped. Oops.

Run two goes much smoother. I get into 2nd before the rev limiter, and just keep it in 2nd. The tire breakway is more gradual, and I'm awarded with soft tire squeal, in contrast to the Camaro's quieter, but abrupt breakaway, race tires.

Overall I am impressed how tight and controllable the Mustang is. I expected a rental race car to be rattling and squeaking, but this car was as nice and tight as any new car I have driven. The suspension was very well dialed in and easy to drive hard. I had expected a ton of understeer (generally safer for beginners), but the car was better balanced than I had expected. My only performance quibbles were having to stop for first gear (not a big deal on the track, you only use 1st to start, but 1st is handy for autocross), and just a hint of incipient wheel hop on hard braking (very mild, many people would probably not have noticed).

The "brain dyno" (and perhaps a little incoming bias) tells me the Camaro was easily faster. I stop by the timer -- I can hardly believe my eyes -- I was faster in the Mustang! This is very amazing, considering I took just 2 runs, and it was on street tires.

How could my impression be so far off? Here are post analysis thoughts:

• A "brain dyno" is not very accurate
• The earlier and flatter torque curve of the Camaro made the launch a bit better, but the Mustang might have been pulling harder at high rpm
• The race seat held me in very well, so I wasn't using my arms to stay in place like usual, so it didn't feel like I was working hard
• The Mustang has slightly better visibility
• The Mustang is a bit narrower