Re: HCH11 CVT Mods.
Harold, I think the CVT and engine are already operating at optimum rpm and torque levels.
There's a Honda tech paper about all the features of the engine and CVT, ty to find that one. Here are the main things I remember.
1. Electronic throttle. This means the accelerator position has not much to do with the actual throttle position.
2. Dual spark plugs, that fire in sequence or simultaneously depending on load and rpm.
3. Variable valve timing.
4. Valves can be completely opened or shut for 1, 2, 3 or all 4 cylinders.
5. At low rpms, only two of the four valves per cylinder will be used, to increase torque.
6. Assist and regen by electric motor.
7. CVT completely electronically controlled. No torque converter (so no lock-up needed).
From what I understand, the controller will try to drive at fully open throttle always, since it is most efficient. Instead of using the throttle, power (and output torque) is regulated by the gear ratio, the electric power assist/regen, and by shutting down cylinders. This might be what you experience as the "propeller with low pitch". Whenever more power is needed, the controller will change gear ratio and increase rpms (since the throttle is already fully open, it can't get more power from there). This feels different from a normal gas engine/gear box combination.
Example, when driving at 110 km/h, engine speed will be around 2000 rpm. Most likely, the 1.3 L engine is at full throttle then. (That is also consistent with the torque figures from Honda, and with the fuel consumption at that speed.) Only way to get more power is to increase rpms.
At low speeds and idle, throttle will not be fully open obviously. And during short periods of time when changing gear ratio, for example when you lift off after a quick acceleration. Also, I have noticed that when driving at above 125 km/h, the CVT/engine will lock at a semi-constant rpm. That probably means the throttle is actually used to regulate power.
I have no actual proof that this is how it works, it is only based on my own experience and reading.
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