Well I really want to know but I don't think it's going to matter anymore because UpRev will never tell us how it works specifically because there are several ways it can be done. For some old school ecm parts and tuning check out MOATES.net. Very informative place you can see the different kinds of chips, emulators, software, cables, sockets, adapters that I'm familiar with tuning. Of course that was pre CAN-BUS, back when all the manufacturers used the same technology and if you knew one you knew them all. Worked great until 96, then they actually made it easier because now you could reflash right through the OBDII connector when manufacturers started using rewritable chips. Some manufacturers still retain this level of setup like GM. The code remains very similar year to year so programs like HPTUNER and EFILIVE are WAY WAY WAY ahead of where Uprev is. They make Uprev look like a real waste of money and give you just an awesome level of control over the entire vehicle. You could set fan on off times, delete egr, change how the electronic throttlebodies work, change ALL of the factory fuel and timing values for idle, turning on the A/C, light load, lean cruise, WOT, Acceleration Enrichment, Target AFR, VE, MAF, TPS%, Main ignition map, decel modifier values, min idle rpm, and many more. The GM stuff for the simple American cars makes me wonder why our cars are called tuner cars when you can hardly do anything with them. On the GM stuff you can even go in and change how you want the automatic tranny to work and shift. You can actually up the line pressure and change shift points from your laptop. If uprev and Cobb could match that kind of control, you wouldn't see half the standalone and piggyback sales you see now. You would be able to have an outrageous setup without having to sacrifice drivability, or traction control, and with out having to ignore the permanent service engine light on the dash. Why
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