Originally posted by OKTurbo
Me too Ted....
I can't figure out if Steve and Bruce are agreeing or disagreeing :O
John
LOL
Some of both!
It has nothing to do with the topic of this thread. Bruce takes issue with my comments that trying to get a magic number out of wot tps settings is futile for Power Enrichment as the the factory engineers put 78% of the fuel trim in at 50% tps (2.5 v) and 100% of the trim in at 75% tps (3.75v). From there on out, there is no additional enrichment. To me, there is no point in worrying if the tps voltage reads 4.2 or 4.7 at wot as there will be no more fuel addition.
Bruce correctly points out that some chipmaker might go in and add more fuel at the 88% level (4.4 v). At least I think that is his point.
I believe that this is immaterial because of the multitude of tables that interact and invoke enrichment based upon engine load, rpm, etc. The fuel needs to be there quicker.
I think (which does not make it a fact) that the factory understood that fueling depends more on actual load than on throttle postion and arranged to get the fuel in when it is actually needed. For street cars, this can often be at part throttle when half throttle is rapidly applied and the boost comes up fast. In my car, at least, there is nothing linear between boost and throttle position.
Likewise, I suspect there is nothing linear between air flow and tps either and this may be another reason the factory dumps the fuel early and gets it all in well before wot.
It's an extremely complex subject and one has to look both at the trees and the forest. There is a good chance that we are both as wrong as we are right. I just like to argue with Bruce because earlier in my career I was in charge of an R&D department and he reminds me of some of the guys I knew then.