From the listing for this Ferrari F40 Race Car for sale:

This car, chassis 85690, is a race winning example of only 16 recognised Competitizione F40’s that were prepared for GT racing in period. This car is one of the most well-known and widely documented of the F40’s that ran in the Italian GT Championship culminating as one of the 3 car official ‘Ferrari Club of Italia’ Team Cars in the 1993 season. The car was delivered new to Pierre Popoff of Lerici Italy in July 1990. Popoff was a close friend of Enzo Ferrari and his construction firm helped build the Mugello racing circuit. As an enthusiastic member of the Ferrari Club Italia Popoff had the car modified for racing in the inaugural 1992 season of the Italian GT championship and continued to contest the car in 27 rounds of the championship between 1992 and 1994 including two wins in the final year and seven podiums on other occasions. The car was initially prepared for the 1992 season by Nicomedi however work and support was swiftly entrusted to Ferrari’s close collaborator Michelotto and it was supported by them for the remainder of its race career including numerous upgrades to ensue the car remained competitive as the series progressed. The car is extremely well documented and appears extensively in the definitive book ‘F40 da Corsa’ and has been the subject of various reviews in other publications over the years. At the end of its competition career the car reverted back to use as a road car. In 1997 the car was imported to the UK where it has resided ever since and has been looked after by primarily Maranello and more recently Bob Houghton Ferrari. In July 2008 the car was granted full Ferrari Classiche certification (Red Book) and then in 2013 with the close collaboration of the original owner’s son, Andrea Popoff, the car was carefully and sympathetically converted back into its 1993 race livery and specification whilst also keeping the car usable as a road car.

From Wikipedia:

The factory never intended to race the F40, but the car saw competition as early as 1989 when it debuted in the Laguna Seca Raceway round of the IMSA, appearing in the GTO category, with a LM evolution model driven by Jean Alesi, finishing third to the two faster spaceframed four wheel drive Audi 90 and beating a host of other factory backed spaceframe specials that dominated the races. Despite lack of factory backing, the car would soon have another successful season there under a host of guest drivers such as Jean-Pierre Jabouille, Jacques Laffite and Hurley Haywood taking a total of three second places and one third.

Although the F40 would not return to IMSA for the following season, it would later be a popular choice by privateers to compete in numerous domestic GT series including JGTC. In 1994, the car made its debut in international competitions, with one car campaigned in the BPR Global GT Series by Strandell, winning at the 4 Hours of Vallelunga.

In 1995, the number of F40s climbed to four, developed independently by Pilot-Aldix Racing (F40 LM) and Strandell (F40 GTE, racing under the Ferrari Club Italia banner), winning the 4 Hours of Anderstorp. No longer competitive against the McLaren F1 GTR, the Ferrari F40 returned for another year in 1996, managing to repeat the previous year’s Anderstorp win, and from then on it was no longer seen in GT racing.