Quote Originally Posted by Thatdudeorion View Post
Oh and also, SteveO and I have discussed EGR a little bit in the past, and I basically coerced him into adding the EGR control to the latest release of $EEx. Thus far, I've tested it, and it appears he is still correct, in the sense that I've had the best fuel consumption results from overriding it to 0% all the time. This doesn't make sense based on the theory of EGR and results that I've seen from other engines on the EcoModder forum, but apparently the LT1 seems to not like EGR. I'm sure it cuts down on NOx or HC or whatever for emissions reasons, but it appears to come at the cost of slightly increased fuel consumption. Though it does seem to reduce knock sensor counts under acceleration...I think...
I haven't played much in the 95 caprice's code to date other than shift parameters so can't comment on fuel economy improvements. Nor my 91 caprice. However, I do search for economy in my mustang. In it's case, (EGR can be shut off easily) lack of egr costs me at least 1-2 mpg. Now, the thing I have yet to verify is if it is do to the lack of the egr or... additional spark advance lost. The mustang has a table that adds in additional spark based on egr flow (interpreted by egr position sensor) and LOAD. Not sure the equivalant in EE$ Load is approximately same as VE. The cam being more than stock at 216/224 degrees starts getting into that 'built in egr' effect cause of the increased overlap. So maybe it really is the lack of additional timing. So egr gains/losses in economy may be dependent on things like the camshaft too.

On the O2 switching, that is another nice feature of the fords is that you can alter the switch voltage. The guys do use this like you're thinking. Another nice feature is the hego bias table that effectively controls the dwell time above or below stoich. Which helps bias the AFR to either above or below. You just can't too crazy with it. If the eec doesn't see enough switches, it may fail the sensor.