I have just recently installed a ScanGaugeII on my car and have been intrigued with the HSD and learning all that I can about this amazing vehicle. I have a 52 mile RT commute each day on a 55 mph speed limit highway and of course run on cruise control at 60 mph. I have noticed that the MG2 RPM = 7000 at 60 mph displayed. So I began to do some research here on PC to determine the gear ratios and the relationship between MG2 rpm and mph. I came across an earlier thread where there were discussion of the improvements of the Gen III over the II. I came across a post by HTMLSpinnr where he gives the gear tooth counts of the complete HSD system. I have taken those gear tooth counts and applied them to the MG2 RPM of 7000 to calculate MPH based on my tire rev/mile. I also found out that the max MG2 rpm = 13500. When using the gear ratios this works out to the Prius max speed of 113 mph. I thought that other newer PC members like me may be interested in these calculations. If anyone sees any errors in my calculations please let me know.
With the addition of SRU, the speed relationship for MG1, MG2 and Engine has to be updated. Equation 1: ws = ( 1 + R ) * wc - R * wr where ws = Angular speed of Sun gear = MG1 RPM * 2 Pi() / 60 rad/s wc = Angular speed of Pinion gear = Engine RPM * 2 Pi() / 60 rad/s wr = Angular speed of Ring gear = ( MG2 / S ) RPM * 2 Pi() / 60 rad/s R = Gear Ratio of PSD = 78 / 23 * 23 / 30 = 78 / 30 S = Gear Ratio of SRU = 58 / 18 * 18 / 22 = 58 / 22 Converting all rad/s to RPM and substitude into Equation 1, MG1 = ( 1 + R ) * Engine - R * MG2 / S MG1 = ( 1 + 78 / 30 ) * Engine - ( 78 / 30 ) * ( 22 / 58 ) * MG2 MG1 = ( 30 + 78 ) / 30 * Engine - ( 13 / 5 ) * ( 11 / 29 ) * MG2 MG1 = ( 18 / 5 ) * Engine - ( 143 / 145 ) * MG2 MG2 = ( 145 / 143 ) * ( ( 18 / 5 ) * Engine - MG1 ) Engine = ( 5 / 18 ) * ( MG1 + ( 143 / 145 ) * MG2 ) Vincent
Thanks Vincent Now does anyone know how to convert the Gen II HSD animated graphic with these numbers to make a new animated Gen III graphic ??
