Measuring motor stats w/o a dyno?
I'm trying to get my stock p2k and monster all in tip-top shape for race purposes.
Problem is... I don't have a dyno, so I don't have any good way to determine scientifically if my motor prep has made any improvements.
I've got a 3.3v power supply and a multimeter, and I can see that my clean P2k draws somewhere around 5 amps unloaded (5.6 amps with a break in fan). Can I use changes in the current draw to infer anything about changes in motor performance?
Also, does anyone have any info on making a DIY rpm sensor? My multimeter has a frequency counter on it, and it seems like I could perhaps rig up an RPM sensor if I could find a proper hall-effect sensor (like used in integy's dyno)