Only two teams – Patrick Racing and Porsche North America  – used March chassis in the 1990 PPG CART World Series. Prior to 1990 Morales Motorsports closed down and Patrick Racing took over the Alfa Romeo project with Guerrero driving the No. 20 Miller Genuine Draft March 90CA-Alfa Romeo Indy V8. Patrick entered second car for star veteran Al Unser Sr. to race at two major speedway events of the year – Indianapolis 500 and Marlboro 500 at Michigan Speedway. Unser qualified 30th at Indy and finished 13th. After dropping out at Indy, Unser crashed in practice at Michigan and broke his leg. He quit the team after the crash.

SeasonSeriesEvent
1990PPG Indy Car World SeriesIndy 500
Driver No.Entrant
Al Unser Sr.40Patrick Racing
ChassisEngineCar Name
March 90CAAlfa RomeoMiller Beer
Scale ManufacturerCollection
1:43Onyx
Cat. No.QualityRarity
071