[ShadeTreeMech]

Not being familiar with the cherokee and Metro, I'm curious to know if both are multiport fuel injected, IE not throttle body injected.

The reason I ask is that I'm confident your Voyager is multiport fuel injected and would likely run E85 without a problem. In my 97 Villager (which incidentally likely has a less sophisticated engine than the one in your Voyager) I could run E85 with no modification, with the expected hit in MPGs. But before I bought E85, I would do the math to figure what MPG on the E85 I had to get to profit from its use. I recall when E85 was ~$2 a gallon and the gas was higher, by using a bit of algebra assuming my average MPGs from straight gas (which is the rule not the exception in Arkansas) I could go further on a dollar using E85 than using straight gasoline. The only downside was a bit of a hard start on near freezing temps from stone cold.

Instead of your miles per gallon, try figuring your miles per dollar if you used E85 in the Voyager. If the Cherokee or Metro are throttle body injected, they won't do well on any ethanol blend, but the Voyager is likely to self adjust for E85 without a hitch and likely to get you more miles per dollar.