Quote:
Originally Posted by 67ragtp
Im in the novice territory with regards to understanding EFI, and trying to understand the technicalities. Im fairly certain that my speed density tune runs closed loop with the short term fuel trims active for idle/cruise normal driving and open loop during WOT relying on Volumetric efficiency tables and PE table. This stuff gets pretty complex, throw in HP tuners 
Thanks for the info- Rich |
Yup, you have it right, SD tunes typically run open loop only during PE mode (higher load). And yeah, factory ECUs are very sophisticated and complex now, and that complexity all comes through in the tuning software. Your garden-variety ECU would have been considered a supercomputer 20 years ago.