Like every other series competing on the streets of Baltimore this weekend, the greatest challenge for American Le Mans Series teams is conquering the unknown.

After recent street races in St. Petersburg, Houston and Detroit have since fallen off the map, only Long Beach will provide a baseline for teams to set up their cars for this weekend's first run around the 2.1-mile, 12-turn circuit.

Additionally, as in Long Beach, the race is only two hours as opposed to the standard two hours and 45 minutes. Some teams could attempt to complete the race on just one pit stop.

Only eight drivers currently on the entry list competed the last time the ALMS ran on a street course in the northeast region of the country, Washington D.C. in 2002 near RFK Stadium (BELOW).

Jan Magnussen won overall that year co-driving a Panoz LMP roadster and has intentions of securing his second win this season in the Corvette Racing C6.R with Oliver Gavin.

A win is very much needed for the Corvette pairing as they enter 22 points behind the leading BMW Team RLL pairing of Joey Hand and Dirk Mueller. Despite a three-race winless drought, top-five finishes in every event have kept them in prime position for the driver's championship in GT.

Those two are the top dogs in points but the last two race winners, Risi Ferrari and Falken Porsche, are surging quickly. And if street course history is anything to go by, Flying Lizard Porsche should play a major role in the weekend. Prior to Long Beach, Jorg Bergmeister had won four straight street races dating to Detroit 2008. He and Patrick Long, who swept the Pirelli World Challenge races at Infineon this weekend, still seek their first ALMS win of the season.

In both the teams' and manufacturers' championships, BMW also holds 27-point leads over Corvette. An interesting sub-headline going into Baltimore is the tire manufacturer standings, as Michelin took the lead over Dunlop for the first time at Road America. That difference is merely one point — and how the tires hold up over the street course will certainly play a vital role in who's holding the trophies come Saturday evening.

The only bullet Michelin has in P1, Muscle Milk Aston Martin Racing, has an “old new” face returning to a prototype in Romain Dumas. The Frenchman will co-drive with Klaus Graf as Lucas Luhr misses his first ALMS event of the season on FIA GT1 World Championship duty in Ordos, China. Dumas and Graf won in the team's Porsche RS Spyder at Mosport last season in their last start together.

“Learning the track itself is a fairly easy process for me, walking the track on Thursday will be important but my top priority will be getting comfortable with the Muscle Milk Aston Martin and getting to know my new work environment, like learning all the buttons in the car and on the steering wheel as quickly as possible,” said Dumas, whose first stint behind the team's Lola Aston Martin will come in Friday morning practice.

Graf still trails the Dyson duo of Chris Dyson and Guy Smith by 18 points; those two are back on level numbers after a post-Road America adjustment of points clarifying minimum drive time requirement from the prior round at Mid-Ohio.

Gunnar Jeannette has won both prior street races in the LMP Challenge class, this year recording CORE autosport's first class win with Ricardo Gonzalez at Long Beach. Those two have a seven-point lead over Genoa Racing's Eric Lux in the class; Lux co-drives with Elton Julian this weekend, which enhances Genoa's victory chances.

A last-lap win for Tim Pappas and Jeroen Bleekemolen in their Black Swan Racing Porsche netted Pappas four crucial points to build his GTC class lead to 11 over Spencer Pumpelly and Duncan Ende of TRG. Pappas and Bleekemolen won at Long Beach earlier this season. Dion von Moltke and local Baltimore driver Marc Bunting might get additional support from the crowds in the second TRG entry.

Four LMP1, 13 GT (Robertson Racing's Fords skip the weekend), seven LMPC and six GTC make up the 30-car field for the inaugural running of the two-hour Baltimore Grand Prix.

• The ALMS Baltimore Grand Prix airs on ABC Sunday at 4 p.m. ET., and is also available live via web-based ESPN3 on Saturday, starting at 3:15 p.m. ET.