F1 is regarded as the pinnacle of motor racing. Advocates of CART (Championship Auto Racing Teams Inc) sometimes challenge this crown on the grounds of outright speed and closeness of competition. In reality, although the open wheel cars look similar, the two series are very different in philosophy, organisation, the deployment of technology the level of competition and team involvement.

The CART series runs slightly longer than the F1 calendar, and includes a more diverse mixture of race circuits. The 2001 season was comprised of twenty one races in seven countries on super speedways, banked ovals and street circuits. In comparison, the F1 series is more international, with seventeen races held in sixteen countries on race tracks and street circuits. The fan base for F1 is also more geographically diverse and the worldwide TV audience is steadily growing, while the smaller CART audience has been declining over the last 2 years.

On first appearances, CART and F1 cars look very similar. Both have open wheel bodies of a monocoque design, constructed using a carbon fibre, honeycomb sandwich. Both cars also have the engine placed behind the cockpit, have two wheel drive and steering, use electronic measurement and data telemetry to monitor and control car performance, employ similar aerodynamic elements to generate downforce, such as front and rear wings, neither use driver adjustable or movable surfaces, and both use similar suspension geometries.

However, to deal with the higher speeds and G-forces that are generated on the banked oval circuits, CART cars are approximately 800kg — 200kg heavier than F1 cars with driver and fuel. CART cars are also slightly longer and wider but have close to the same wheelbase. F1 cars are generally more nimble – quicker through corners and therefore around street circuits. This is primarily due to a combination of lower weight, slightly wider tyres and lower engine mass that allows quicker revving. CART cars, however, excel on the fast ovals. They have the advantage of additional traction and downforce because they employ ground effect aerodynamics in their underbodies and run on slick tyres, both of these features are currently banned in F1.

The engines used in both series produce similar power, currently around 800-850 bhp, with the output from engines used in CART being slightly higher but at a lower rpm (14,500 versus the higher-revving F1 engines which peak around 18,500). This power is produced in different ways; CART regulations limit engine capacity to 2.65L, and engine configuration to a maximum eight cylinders with four valves per cylinder, but allow turbocharging and high octane methanol fuel mixtures. F1 regulations allow engines to have a larger 3.0L capacity with a configuration of 10 cylinders and a maximum of five valves per cylinder but ban all types of supercharging and turbocharging and limit fuel to commercial low-lead gasoline. CART engines are significantly heavier than their F1 counterparts because of the turbocharger and the additional bulk required to handle the stresses from turbocharging and the high octane fuel. In CART the fuel tank can hold a maximum of 35 US gallons, while in F1 onboard fuel capacity is theoretically unlimited.

Most of the technology used in motorsports today has either originated or has been developed in F1. A lot of this technology has subsequently been banned or limited by regulations, as the FIA (F1's governing body) attempts to promote a good level of competition while improving safety in the sport. This directive often leads to deliberately limiting speed. Minor and sometimes major modifications are made to circuits, altering corners, adding or removing chicanes and sometimes changing completely the layout of a sector. As for the cars themselves, ground-effect aerodynamics, for example, which was first developed by the Lotus-Ford F1 team in the 1970s for the classic JPS Mk III and Mk IV cars, were banned by the FIA in 1982, but are still used in a modified way in CART. Other F1 technologies, such as traction control, have come, gone and been reintroduced.

While the FIA keeps the regulations in flux, season to season, the teams do everything in their power to find performance gains, constantly pushing the sport forward. This drive for technology improvement in F1 is a direct result of the way the sport is organised. CART's governing regulations are relatively static and competing CART teams purchase engines and chassis from third party manufacturers, so there is less research and development. In comparison, F1 teams are responsible for the design and development of all aspects of the car. Very few elements of the car are purchased from third parties, and, as mentioned above, the FIA takes an active role in continually tuning and modifying the regulations. All this leads to greater innovation and diversity in the technology applied in the sport. F1 has a total of 20 chassis and engine developers competitively working on different solutions, compared with the 2 chassis and 3 engine suppliers in CART. This level of technology development requires large teams with a large range of diverse skills, larger budgets, and a closer working relationship between the car, driver and the other members of the team.

Very few drivers have successfully competed in both CART and F1. Generally drivers have enjoyed more success moving to CART after a successful career in F1, rather than the other way around. Alex Zanardi and Michael Andretti, for example, are both previous CART champions that have found it difficult to find equivalent success in F1. Two exceptions in recent years are 1995 CART champion Jacques Villeneuve, who won the 1997 F1 World Championship driving for WilliamsF1, and 1999 CART champion Juan Pablo Montoya who has already achieved one win and two lap records in this, his rookie F1 season.

Juan Pablo Montoya first experienced the dynamics of F1 during his term as WilliamsF1 test driver in 1998. Now one of the sports most talked about competitors, he has made the dramatic technological and mental leap from CART, taking it in his usual confident stride:

"Most American racing today, generally all the top racing, is much more restrictive about technology. NASCAR, for example, uses four gears while F1 has seven and their time between shifts is about half a second as they have to do it manually, while in F1 we are shifting within four thousandths of a second. The technology makes the car so much more fun to drive. Everything is so quick it’s amazing and it allows me to get the maximum performance out of the car.

"And in the future, I don’t think that the regulations are going to free up much more. For example, I don’t think that we’ll be going to electronic suspension or such major things. There is so much new technology from this year to last year due to rule changes, so we have plenty of things to work on at the moment. You can feel the differences in performance in how much the car has evolved in the last two years.

"F1 is there to show what is possible of a car manufacturer or a car builder. How far they can go with it, and that’s the aim, how much technology you can put into a car."

A different set of regulations for CART and F1 have led to the evolution of quite different cars as both employ different technology. In F1, however, each component is more highly developed and tuned. The largest gap between the sports today is in the use of computers for measurement, testing, analysis and simulation of the car’s performance – at the factory and on the circuit. Juan Pablo explains:

"Apart from the difference in rules, in Formula One there is a lot more computerised equipment in the car. The shifting, differential, engine management, traction control are all more computerised. There’s a lot more sensors in the F1 cars because more things on the car are managed electronically, so there’s a lot more things to analyse and work on.

"I think the most difficult thing is getting the car right. With slick tyres when I was in CART and everything, you can – even if the car is not perfect, you can get a really good lap out of the car. You can overpush the car a little bit. With the grooved tyres in the Formula One, you know, if the setup is wrong, the tyres after two corners they grain or, you know, they lose grip really quick so you need to have a really nice balance in the car to work, so it works together with you. It's a bit more complex.

"You've got to try within the rules of the car, try to maximise a little bit here and a little bit there, yeah? In Formula One, you can go and if you really have a close look of the car, I guarantee out of 17 races, 14 races the car will be different. There will be something different in the car, something new, something small, anything that is going to make the car go quicker.

"After every day of practise we debrief with the telemetry information. Normally the data acquisition guys look into the detail. 80-90% of problems can be picked up through the data, but there is always something that tells you as a driver that something is wrong so you feed this back to the team and if they don’t find it instantly after a good look at the data they will. For me the most fun is driving the car! But also working with the engineers to make the car better is very pleasurable. When you work for two days, come to the race and see the car is really fast, that's great.

Beyond technology and speed, the attitudes, the intangible differences between the two sports are also dramatic.

"The positive surprise is all the poles I've done so far and the win. I didn't really expect my first season to win. I think negative is the atmosphere is so different that it really took me awhile to like get in the groove of it. Because the atmosphere is a lot more tense, you've got to be a lot stronger mentally. I think I consider myself quite strong mentally, and it didn't really affect me. But it took me a while to really focus in the car in what I had to do. It really drives your mind away a little bit.

"Mentally it's a lot stronger. You've got to be a lot stronger than CART because in CART the atmosphere is a lot more friendlier. In the car is very similar, you know. In the car you've got to push the car to its limits, both cars are very physically; but outside, I think outside the car, you know, you see in CART everybody talks to everybody, everybody is friendly. Here you don't even cross a word with anybody. You're there by yourself, and you've got to work with the people around you, you know. I think in a series like this, I think the team is a very important asset."

Any does Juan have any misgivings about leaving CART for F1?

"No, because that's what I wanted to do. All my life since I remember as a kid I dreamed of being in Formula One. I had a great opportunity to come to Williams and, with BMW and Michelin involved in it, it was a great – you know, you could tell the team wanted to move forward. And the way it's been looking, we've evolved a lot. Those opportunities, they don't come every day. That's what I wanted to do. I came to America, achieved what I wanted to achieve and more. In the two years I was here, I think I achieved a lot of stuff. You know, won CART championship, rookie of the year, rookie of the year in Indy, won Indy. I thought 'you can stay here and do those records even greater, yeah, or you can move yourself into Formula One,' and it would be a new task and a new challenge. I decided that was the best way."