I think with the right ecu (from say a dump truck or something emissions exempt, or better yet custom) 460's, 4.9l, and 1.9l fords they all have a habit of doing a weird high NOx thing while pumping egr.
Very sooty, very little mpg loss under load. Crazy timing, and flame speeds going on in those high swirl heads.... But that's waay over my head.
HONDA AND FORD ARE FINED MILLIONS - NYTimes.com
If people feel so inclined, there's a few articles between 1993-1994 where independent researchers were testing a lead substitute for a test blend of fuel (I forget the additive and I lost my links) but the escort was clogging the egr system very quick, and the escort was using "inappropriate enleanment strategies", which blew the lid off of the 91-95 escort ECU's, mainly egr equipped models, but then the 4.9 was found to do the same, and the 460 was usually exempt. But the point is that the torquey fords pre 96 and the 97 Econoline, were pulling a Volkswagen on the EPA. Savage.
A base map shows nothing over 15:1 on these engines, but they cruise at 17+:1..... Fishy.... But I'm not complaining
If the O.P. wants cylinder deactivation, they should hope for an egr valve, clean the dpfe, and clean the valve itself. Just my .02