CLASS CONFLICTS; LMP2 and GT2 will be the talk of the 2007 ALMS season.(Motorsports)

Byline: GARY WATKINS

Four classes, 36 cars: The numbers make the 2007 American Le Mans Series sound pretty good, but the ALMS remains something of an enigma as it heads into the series opener, the 12 Hours of Sebring, on March 17. Two of the classes are stacked full of top-line cars and quality teams and drivers; the other two have the quality but in small quantities, and they are close to one-make categories.

The LMP2 and GT2 divisions are set for a big year. Porsche and Acura go head-to-head in the lightweight prototype division, represented by some of the biggest names in North American road racing-Penske Racing, Dyson Racing and Andretti Green Racing. In GT2, manufacturer-backed teams from Ferrari, Porsche and Panoz do battle. That's the good news.

The bad news is that LMP1 and GT1, in theory the marquee categories, don't make it into double-digit car counts-even with both classes combined. Audi has no real opposition in the top prototype class and is still making noise about pulling out of the series, while Chevrolet is so far the only full-season GT1 entry.

Audi's turbodiesel R10 remains undefeated in eight outings, including last year's 24 Hours of Le Mans. We can hope that the factory-supported LMP2 entries-as many as six Porsche RS Spyders, three Acura-engined chassis and a Mazda-engined Lola-will be able to take the fight to the R10s. That's not what Audi wants, hence motorsport boss Wolfgang Ullrich's criticism of the decision by ALMS and sanctioning body IMSA not to impose a 5 percent cut in engine air restrictor size on the LMP2s (Competition, March 5). Le Mans organizer Automobile Club de l'Ouest wants to maintain a gap between the two prototype classes; the ALMS wants opposition for the turbodiesels and has exercised its prerogative to tinker with the made-in-France rules.

The official line from Porsche and Acura is that they are focused on winning in LMP2. Porsche's drivers, meanwhile, still aren't sure that they will be able to fight the two R10s consistently, even on the street circuits that make up much of the first half of the season. They point out, for instance, that Long Beach has two long straights. What's more, a reduction in the R10s' fuel tank capacity is unlikely to have a major effect over the two-hour-45-minute races that make up the majority of the 12-race season.

Thus, it would be unwise to bet against Audi winning the majority, if not all, of the races, presuming it hangs around for the full season. The smart money is on reigning champions Allan McNish and Rinaldo Capello to outgun the new pairing of Emanuele Pirro and Marco Werner.