there is already a VW with starter/generator, start/stop system and powered by a frugal tdi (PumpeDuse)
development began in the 80's.. went into production around 97/8: the LUPO 3L
EDIT: nevermind, I've researched further, it uses a regular alternator, nice car thou
Now taking your idea of mounting magents on the flywheel coupled with a compression release one might be able to pull it off... The compresion release would be the trickiest part..
i think with a full 120 degree phase alternating current motor, the torque would be really high as compared to the regular dc motor starter. with the right 3 phase inverter (around 400 volts or so) and the right gauge wire and number of winds, i think that a flywheel motor should be able to deliver more than 20 hp for short spurts unless there were extra batteries... considering the efficiency of 3 phase a/c @ high voltage, the 5 seconds or so cranking time shouldn't really drain the battery much at all. the more i've been thinking about it, the better the idea sounds. so far i've been looking at those robotics websites that sell the programming PIC boards. they're pretty cool and have multiple PWM outputs for DC servo motors... some even have PWM for high voltage AC which would be ideal... the more i learn about ac and dc, the more i believe every electric motor on a car should be ac. low amps are the key to reducing heat losses and inefficiencies.
on another note, the more i dig into the truth about Stan Meyer's water cell, the more i'm blown away. the ideas that i've had using his system, apparently he's already thought about
anyone wishing to learn a bit more is encouraged to watch this video:
Stanley A Meyer Water Fuel Cell Free Energy Conference 1989 - Part 1/6i found some
super high voltage, super low amp DC to DC converters, which are required for the Stan Meyer cell. coupled with a PWM, i really want to start testing
some people have said that printers contain these modules though? i'm gonna find some old printers and check it out. i'm thinking only old laser printers though.. for the fuser roller or corona wire.