What about carbureted engines in applications other than automotive? (like the one I'm thinking of ;) ) The well discussed principle of injector pulse proportion & pressures won't help in these cases...... c > Another way of measuring fuel is measuring the pulse width of the fuel > injectors, and if you know the flow characteristics of the > fuel injector > (as well as the speed of the vehicle), you can very accurately compute > fuel economy. -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu