The RS Spyder made its debut in the final event of the 2005 American Le Mans Series (ALMS) at Laguna Seca winning its class.

[2] Since its introduction in 2005, the engine, which initially produced 478 horsepower (356 kW), has been developed and modified to meet the changing regulations of both the ALMS and the ACO.

[2] The RS Spyder made its race debut at the final round of the 2005 American Le Mans Series, the Monterey Sports Car Championship at Mazda Raceway Laguna Seca, entered by Penske Racing and driven by Lucas Luhr and Sascha Maassen from the Porsche Junioren factory team.

[9] Rule changes increased the RS Spyder's weight to 825 kg[10] and Porsche introduce a new direct injection engine developing 503 horsepower (375 kW).

At Petit Le Mans a 3rd RS Spyder was entered by Penske in an attempt to lock out the manufacturers' championship against Acura.

[13] Danish Team Essex together with Van Merksteijn Motorsport of The Netherlands and Horag Racing of Switzerland participate in the Le Mans Series (LMS) all with 2008-spec RS Spyder.

Team Essex and Van Merksteijn also entered the 24 Hours of Le Mans, marking the debut for the RS Spyder at the event.

[20] It was also announced that Sascha Maassen would join the regular drivers Klaus Graf and Greg Pickett at the longer races at Sebring, Laguna Seca and Road Atlanta.

The CytoSport RS Spyder won the LMP2 class at the 12 Hours of Sebring[22] and took their first outright victory at Northeast Grand Prix at Lime Rock.