chassis of the P35 was intended to be built from carbon fibre, yet the initial test chassis were built from a hybrid of aluminium and carbon to save time, due to NPTI's lack of experience with building carbon chassis. For an engine, Nismo would develop an entire new unit. Required to be 3.5 litres by Group C rules, the engine had to not only be high-revving like a Formula One engine, but also have endurance capabilities. Nismo produced an engine at 3499 cc named the VRT35, with claims of and capable of reaching nearly 12000 rpm. The VRT35 would be a V12, in comparison to Peugeot, Toyota, and Mazda's V10 units. Following the cancellation of the P35 project in 1992, the car was briefly considered as a possible replacement for the NPT-90 in the IMSA GTP Championship, replacing the VRT35 V12 with the 3.0L turbocharged VG30 V6 that had previously been used. Wind tunnel tests were carried out on what was termed the 93GTP. However, Nissan was looking elsewhere and decided to pursue Indy Car racing. This lasted only briefly (though Indy Car concepts were beginning to be developed in the wind tunnel) and the realities of the widening recession hit home. This eventually led to the closing of NPTI in 1993. In total, three P35 chassis were built in total for testing purposes. NP35 While NPTI developed the P35, Nismo decided that although the car would be legal for competition in the All Japan Sports Prototype Championship, it was not as well suited to Japan's shorter race circuits. Nismo therefore decided that they would develop their own version of the P35 with an increased downforce setup as well as some other mechanical changes. Nismo used molds originally used for the creation of the P35 to create their own car, known as the NP35. Due to Nismo's access to a carbon fibre facility, the chassis of the lone NP35 was constructed entirely of carbon fiber instead of the hybrid used by NPTI. The VRT35 V12 was also modified with more power because JSPC races were not as long and endurance was not as important. Only one NP35 would be built and raced before Nissan cancelled the project. X-250 In 1992, following the closing of NPTI as well as the cancellation of the World Sportscar Championship, All Japan Sports Prototype Championship, as well as the GTP class in the IMSA GT