I know that OEM types don't like soliciting outside patented ideas, but something you really ought to study is http://www.somender-singh.com
With a little creativity, you might spark on something that can solve your problems.
Mike
It is my understanding that the "air/fuel ratio" is actually an "air/fuel VAPOR ratio". Therefore if the fuel is admitted into the air charge closer to phase change temps, then the "effect" would be an enrichment condition. Of course it would depend on how efficient your combustion chamber...