Pirelli World Challenge SprintX will see an increased field for this weekend’s 58th annual Rose Cup races at Portland International Raceway, with additional GT entries for the series’ return to the Pacific Northwest for the first time since 2005.

A total of 15 GT3/GTC cars are on the entry list for the penultimate round of the SprintX season, along with 35 GTS class entries.

It includes the series debut of Lamborghini Super Trofeo North America competitors Precision Performance Motorsports, with Guy Cosmo and Patrick Byrne set to share the wheel of a Lamborghini Huracan GT3.

The reigning Asian Le Mans Series LMP3 champions are part of the boosted GT Pro-Am class, which grows to a five-car entry this weekend.

An additional GT Am entry, meanwhile, will also be on the grid in Portland, with local drivers Rich and Trevor Baek listed in a Ferrari 488 GT3 entered by Vital Speed Motorsports.

Rodrigo Baptista, who completed alongside Bentley factory driver Maxime Soulet in the Pro-Am class last time out at Lime Rock Park, has since been upgraded to Pro status, with the No. 3 K-PAX Racing Bentley Continental GT3 therefore now in the top class.

Mercedes-AMG factory driver Raffele Marciello, who made his PWC debut last month, meanwhile, returns to the No. 2 CRP Racing Mercedes-AMG GT3 alongside Daniel Morad.

Morad has dropped to sixth in the SprintX standings, 29 points behind leaders Toni Vilander and Migue Molina, of R. Ferri Motorsport.

Vilander, meanwhile, also continues to lead the overall standings, just two points ahead of Pfaff Motorsports’ Scott Hargrove, who will again be joined by ex-Porsche factory driver Wolf Henzler this weekend.

35 Entries for GTS SprintX

A bumper field of GT4-spec machines are set to do battle at Portland for the first time, including the return of several teams to the grid.

Muehlner Motorsports has both of its Porsche Cayman GT4 Clubsport MRs entered, while the No. 66 TRG Porsche GT4 makes a comeback for local driver Derek DeBoer, following a heavy race-ending accident at Virginia International Raceway in April.

Daren Jorgensen and Brett Strom’s BMW M4 GT4 is now under the Classic BMW banner, after a split with Cameron Lawrence, while an additional Maserati GT4 has been entered this weekend by Motorsport USA.

Track action kicks off on Friday, with the separate 60-minute races scheduled for Saturday and Sunday.