UM, there is a throttle body for the ICE. It has a butterfly (or the equivalent).
WOT would be the point where that butterfly is WIDE OPEN, i.e. WIDE OPEN THROTTLE... Which, I gather you are saying could occur at load, on a hill, for instance at somthing other than a fully depressed accellerator. AND that once you have max load on the ICE, the only other place to get more torque is the motor.

I've noticed that I can feel the torque increase on a hill with a fixed throttle postion (as best as I can by digging my foot into the console and not changing it). No rpm change, but more torque from someplace ( I always assumed it was the motor.)...

MM

 

Should of said 'virtual pedal'...

 

I thought it would be the electric motor kicking in, adding is massive torque to the ICE's torque?

 

Last January when Wayne Gerdes (xcel) and I were trying to determine the best acceleration rate in my FEH for the pulse & glide technique, I found that it was very hard to stay out of motor assist. Accelerating very slowly, I tried the hold instant MPG at 10-15mpg, 15-20mpg, 20-25mpg and 25-30mpg without motor assist. What I found was, the ICE was at max load between 15-20mpg. Max load is all the torque you get from the ICE at that MPG. Without the elec. motors, the FEH would not get out of its own way at low RPM's.

If I had manual linkage and went WOT, the ICE would probably accelerate even slower and less efficient. With manifold pressure sensors etc., the PCM regulates the electronic throttle body and fuel injection for max efficiency at max load. So the term WOT is still used because your at the max load of the ICE.

What I do for max efficiency during acceleration now is go to an RPM where the torque curve is best, and hold it there till I reach the speed I want. This allows the eCVT to adjust the gearing the most efficient way. I may be at WOT with assist for a few seconds, but I try to keep out of WOT and assist as much as possible though. For the best pulse, I go to 1800rpm's and hold till I reach glide speed.

Graphs of the FEH ICE torque curve are located at:
http://www.cleanmpg.com/

GaryG

 

I have also thought about adding an alternate source to keep the batteries charged, but instead of toting a trailer around, why not use a small stationary plateform hooked into a trailer hitch mounted on the back of the vehicle ... it will add what maybe 3 feet.

 

That's what seems to work for me as well. I wish I had the time to do a bunch of recursive tests about what rpm allows max torque. I am beginning to think it is at about 2300 rpm. I seldom accellerate that hard though.

One of my other cars is an 88 Mustang GT with an Eaton Blower on it. Getting it to run properly required that I get fairly deeply into programing the computer. I suspect that the same variables I used are usdd by the FEH. On the fuel maps that I worked with, load was a variable that was calculated from throttle position, manifold pressure, barometric pressure, rpm, and feedback from the O2 sensor. EXCEPT when at WOT, which took the engine OUT of closed loop and ran an entirely different fuel map. I suspect that the engine is most efficient at max load, but not at WOT.

MM

 

Oops, the computer also calculated the amount of air getting to the engine using a hot wire mass air meter. Again, part of the load calculation.

 

Mark, everything I read say WOT or max load is the least efficient. I try to stay less than 80% load in my FEH when I can. The least amount of load = the best MPG. At idle with the ICE running the A/C compressor and turning the generator, the load can be over 70% sometimes. Last time I checked, without the A/C or generator was around 30% load on the ICE.

GaryG

 

WOT efficiency...

Take a short piece of PVC pipe, open at both ends and suck on one of the open ends.

Now put the palm of your hand tightly over the other end and suck again HARD.

The latter is a simulation of pumping losses, when the throttle valve is fully open, WOT, pumping losses are at an absolute minimum, the engine can suck "pump" all the air its RPM and capacity dictates.

With pumping losses at a minmum the engine now operates at its most efficient.

That's also the way K&N sells folks a "load of poles", they claim improved HP/torque by eliminating the pumping losses of the air filter at WOT and top RPM.

Absent being out on the track at Daytona just how often is "your" engine at WOT and near or at top RPM?

Not often enough to warrant the resulting "suffering", contaminated MAF/IAT sensors and premature engine failure.

 

Gary: