Recent Enginer install

Hello,

I recently install a 4 kwh Enginer kit in my 2005 Prius and wanted to let everyone know of my experience. I bought a used 2005 Prius for the purpose of converting it to a plug-in hyprid. (BTW, I have been driving a 2009 Honda Civic Hybrid for two years and my wife has a 2010 Honda Insight which I drive periodically. Yes, I have been a Honda person for many years, but the prius has better all electric operation and is clearly more suitably to PHEV operation.) I only had 1 month of Prius baseline operation before installing the Enginer kit, but I could get 60 - 63 mpg for a tank during warm weather. These are scan guage numbers backed up by tank-based refill numbers. Unfortunately, the MFD seems to give numbers 3 - 4 mpg higher than reality, admittedly without a lot of statstics. (Interestingly the Honda onboard computers always yield numbers 1 -2 mpg low, I'm not sure why this is, but that's what I've seen.) For the prius baseline, individual days could be as high as 70 mpg for my particular commute, for the whole tank, my numbers were a bit lower. I installed an engine block heater and I run 42 - 44 psi in the tires and attempt to hypermile, etc. (I don't really use pulse and glide as I don't seem to practically understand this.) In any case, with the Enginer 4 kwh kit installed for almost a month, I can now get 80 to 85 mpg for my compute (46 miles round trip, as much as 70-80 miles some days). I am very happy with the kit. I have been able to drive 20 miles in all EV mode (under 34 mph) with 4.9 kwh added back to the pack giving ~250 wh/mile for my test so far. (BTW, I also have an all battery EV 1976 MG midget with lead acid batteries where I get 330 to 350 wh/mile. Obviously the prius has better aerodynamics.) Anyway, the Enginer kit has yielded days as high as 99 mpg and as low as 75 mpg (again for my commute). My Enginer mpg numbers are certainly lower due to lower temperatures as winter approaches and morning temperatures are lower now compared to my baseline numbers. Overall, I think the Enginer kit is really more suited to someone that is willing to tinker and play with their system and not neccesarily for non-technical folks that want a solution they don't need to monitor. I find myself turning off the system when aproaching hills and stopping to charge the Prius battery if the Prius battery gets near 4 or 5 bars. For me, charging frm the outlet has been totally automatic...no monitoring of the charging. The system also shuts off when the voltage drops below ~46 Volts on the Enginer pack. I have the 5000W DC-DC converter...this has been giving 10.5 amps or so at the prius battery voltage (230 Volts or so) when offseting 1 - 2 amps of baseline usage as per the scan guage. I may try to bump up the DC-DC output voltage a bit moving forward (tinkering). I also find it disconcerting that I never really know how much current is flowing from the li-ion pack as the amount of current depends on the prius battery voltage which varies depdending on whether the car is accelerating or in regen. I guess I need to install a current sensor for the Li-ion pack. BTW, I have the realforce battery packs. Again, I am very happy with the system and am planning (i.e. trying to find $3500 in the budget) to get another 4kwh system to make it an 8kwh system. Based on previous reports from 1 - 2 years ago the system is much more user friendly now with respect to charging and balancing. Since my commute is mostly downhill on the way to work, I am still looking for a a good solution to get past the 34 mph EV limit. Also, since I am traveling downhill, I think the engine is currently running to keep the temp near 157F wthout me actually using engine power. I may try the 52 mph cludge soon to see what this does for me, but this is doesn't seem like a good solution to me. I am looking or something more elegant. Overall, the 20 miles in EV mode is reasonable and achievable (if careful) and the 40% improvement as claimed by others is consistent with my experience with the Enginer pack. It is clear to me that for someone that drives in a city with 25 mph speed limits and short commutes (not me BTW) they could stay in EV mode and get almost unlimted mpg and this would be a cheaper solution than a 2012 toyota PHEV. Basically, I didn't want to shell out the money for a 2012 Toyota PHEV.

Art