Originally posted by RiftsWRX
It makes for a smooth transition... but a dangerous one... the TXS unichips were originally TPS, and our first gen UTEC (which I still have the beta board at home) was TPS based.... but that smoothness quickly became a liability...
Case in point.... if your go to 50% throttle in first, that may be 5 PSI... but in 5th that's 25 PSI.... if your running the same timing... that's bad.... very bad....
I'm a UTEC user too, but that's no excuse for a clear misunderstanding of how the XEDE can use the TPS signal.
In most cases it would be setup as jehcpa mentiones, Yhe XEDE tells the ECU TPS is > 60%, then makes the appropriate timing and fueling changes based on the load of the user's choice. It does not have the inflexibility of the Unichip in only choosing ONE load map.
Also, there are times when piggybacking the stock timing curve is useful. Most
of the time the stock ECU changes timing, it does so for a reason
When you eliminate the stock ECU learning bad behavior, (ECU in closed loop, with piggyback trying to make fueling changes, for instance) piggyback tuning actually makes a lot of sense. The safety features built into the ECU still exist, and you don't end up in danger of the stock ECU detecting knock that the UTEC doesn't, then suddenly switching fuel maps on you (from the low det to high det map) since the stock ECU can't correct that knocking in any other way.
There are advantages and disadvantages to both methods. I'd understand them before misrepresenting a competitor's product.