Haltech Elite 2500 Fast Facts. The Elite 2500 is a two-connector ECU, recommended for popular, late-model performance and racing applications. Suitable for engines with up to 8 cylinders or 4 rotors, Drive-By-Wire (DBW), EFI conversions and engines with multiple variable camshafts. ---------------------------------------------------------- - Nexus Software Programmer (NSP) real time calibration software - Wide range of crank trigger patterns supported - 4 Sensor Variable Cam - Drive-By-Wire Supp