Roush Performance debuted the car at the
1987 24 Hours of Daytona under the 'Roush Racing' banner, selecting
Scott Pruett,
Pete Halsmer and
Tom Gloy to drive it. Unknown to Maxum, Roush had signed an exclusive deal with
Bridgestone, meaning that the car was run on Bridgestone Potenza tyres rather than the Goodyear Eagles that the car had been designed for. This led to handling problems and a suspension failure after 120 laps consigned them to 58th place overall, and 14th in the
IMSA GTP category. After Daytona, the car was booked into the full scale wind tunnel at Lockheed Martin, ostensibly for aerodynamic development. John Dick, the Roush team manager, was in charge of the test and prioritised setup over aerodynamics, leaving the Maxum staff largely sidelined. Unfortunately Halsmer hit the wall on the last lap, causing significant damage to the car which resulted in them missing the 1987 Sebring 12 Hours while the car was returned to Roush's shop in Detroit for repairs. The
Grand Prix of Atlanta saw Roush retire after 45 laps, restricting them to 22nd overall, and ninth in the GTP category. Although the team finished the next race, the
Los Angeles Times Grand Prix, they could do no better than 15th overall, and seventh in class; last of all those still running at the end of the race. Things didn't improve at the
Monterey Triple Crown either; a blown engine after 25 laps saw Pruett finish 22nd overall, and 12th in class. The
Lime Rock Grand Prix saw a strong return to form, as Pruett and Halmser took second overall, finishing 37 seconds behind
Al Holbert's Porsche 962; Holbert's 962 and the Mustang Maxum GTP were the only two cars on the lead lap.
Davy Jones was selected to drive the car at
Grand Prix of Mid-Ohio; he retired after 23 laps, being classified in 23rd overall, and ninth in class. By now, the car had been fitted with a 7-litre version of its Ford-based V8 engine, and the
3 Hour Grand Prix of Palm Beach, where Pruett was partnered by
Whitney Ganz, saw the team finish in tenth overall, and fifth in class. Halsmer returned to partner Pruett at the
Camel Continental; the team, who were now running under the
Applicon/Roush banner, retired after 98 laps and were classified in 15th overall, and fourth in the GTP category. Two further entries, at the
California Grand Prix and the
Grand Prix of Southern California, were lodged; but the Mustang Maxum GTP did not run in either of these. Pruett, who had driven the most races with the car, was classified 16th in the Driver's Championship, with 47 points, whilst Halsmer was 19th, with 41 points. ==Legal Action==