A mechanical adjustment depends on the year. 12 valve B5.9s: yes. Big difference. 24V electronic ISBs: no point. The timing is electronically controlled in the VP44 injection pump. Adjusting the mechanical timing of the pump won't have much of an effect. I know some aftermarket tuners only alter fuel metering while others alter both metering and timing. For economy you would obviously want the latter. I would go with a tuner before tinkering with various resistors in place of sensors with the Dodge. On the other hand, resistors are really really cheap.
