Can't tell you much more than the title says. In a moment of inattention going down a fairly long steep hill that I'd entered a Neutral glide with Ice-off I exceeded 64mph breaking the theoretical 62mph/10,000 rpm barrier for MG1 under those conditions. And nothing happened. I was not on the proper screen to see what rpm MG1 was actually at on my CAN-View. No warning lights, no smoke no screaching, nothing happened. AFAIK I'm the first/only one to post such a situation and I'm just getting it in the archives for future reference.
There is always a design margin. A good engineer allows at least a 10% margin, so if this is the case in the Prius, it should do 11,000 rpm before it flys apart. Good to know one can get at least to 10,000 without trouble.
I did same thing last month. Drove up to 102km/h(63.4mph) actual or 108km/h(67.1mph) displayed speed, and the calculated MG1 speed was 9333rpm. Nothing happened. Ken@Japan
Good call -8900rpm & + 7800rpm were the min/max. Interesting. It seems that the formula predicted number are off.
I think there was some discussion here that the Prius would spin the ICE even in neutral to prevent MG1 from overspeeding. I can't find the thread right now, though.
We wondered if it might kick in the ICE, but nobody's seen that happen. It definitely did not kick in the ICE in my experience today.
Alanh, I believe your confusing it with Drive. The only way to get the prius to 64mph in neutral with the ice off is to get into neutral with the ice off before you hit 41mph, and then accelerate to 64mph (by gravity). Neutral "locks" in the state of the engine at the moment in which you activate it.
I did a little scangauge test a while ago regarding this. What I found was that if the ICE was already running when put in neutral (i.e. at over 41 mph), the ice rpm would continue to spin up correctly in neutral even though no fuel was being used, no matter how fast you ended up while coasting downhill. On the other hand, if you put the car in neutral while the ICE isn't running (in my example, 38MPH), the car will accelerate well over 42 MPH without the ICE rpms spinning up. I ran it up to 50 MPH before running out of space and nerve, and still registered 0 rpm on the scangauge. I'm guessing here, but I suppose that would make it less than advisable to switch to neutral if you are starting under 41 mph and planning on coasting up to high speed.
I think this was the post I was thinking of: Although it only mentions MG1/2, I think the last point implies that it will start whatever is necessary to avoid destroying MG1 even in neutral. It might not "start" the ICE, it may only spin it ala warp stealth.
FYI, Attached graph is my log. During my down hill driving, I shifted to N at 1:21'45", then shifted back to D at 1:23'59". Ken@Japan
