Posted by Harry Smith on January 28, 2009, 12:14 am
We are talking with a Southern California Company (Jungle Motors) about a
Prius kit which is claimed to provide 40 miles of electric only driving, up
to 52 MPH. The kit includes a 10kW battery pack, some circuitry changes,
Has anyone had experience with Jungle Motors, or installed their kit? Any
information would be greatly appreciated.
Thanks for reading this post.
Posted by Elmo P. Shagnasty on January 28, 2009, 12:30 am
The current Prius HSD *cannot* go faster than 42mph on electric alone...
Posted by Harry Smith on January 28, 2009, 3:29 am
True -- they have a couple of circuit boards that they say gets around that
limitation. For us it is a deal breaker if they turn out not to be
Posted by Mr. G on January 28, 2009, 4:35 am
The reason for the 42 MPH limit in electric-only mode is that if the ICE
is stopped, then the electric motor (MG2) must spin faster at a given
speed. At 42 MPH, MG2 is at its redline RPM. If they are using a
circuitry change to get above 42 MPH in electric-only mode, they must be
doing 1 of 2 things:
1.) Using MG1 to spin the ICE, similar to what happens in 'B' mode
2.) Allowing MG1 to spin faster than what Toyota rated it for
Option 1 is putting wear on the ICE, not to mention friction in the
overall drive system, making the electric-only mode much less efficient.
Option 2 is something I wouldn't even want to try. I have no doubt the
motor could spin faster than its rated speed, just as a regular motor
doesn't automatically self-destruct when you hit redline. But I
wouldn't want to have it do that in the normal course of driving.
I did a quick Google search on the Jungle Motors conversion, including
their Web site and some press releases. They all mentioned the 40+
miles on electric, but I saw no reference to top speed in that mode.
Posted by Elmo P. Shagnasty on January 28, 2009, 2:42 pm
Hmmmmmm. As I understand the current HSD, that's not an electrical
issue that can be fixed with some circuit boards. It's a physical
limitation of the motor/generators.