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Can I try to explain the difference between torque and power and which is suitable for CVT?
When an engine burns fuel in a piston engine the combustion creates a pressure to push the piston down. Some engineers call it brake mean effective pressure. The more pressure on the piston the greater these values called torque and power FOR THOSE engine revs.
A camshaft is always a compromise in when it should time the opening and closing of a valve. A racing engine around a town is a pig because the cam won't allow it to pull at low revs, but it is a dream at high revs. Conversley a diesel cannot run fast because its big fuel molicule burns slower than petrol. So its camshaft is designed for low revs; the camshaft is designed to ensure maximum filling of the cylinder with air and fuel - you can design a petrol to pull at low revs.
So the more air and fuel in EACH piston stroke meas more torque. If you like the amount of power from each piston stroke. But what if we double the revs from the maximum torque figure of 2500 revs to 5000 revs. Each piston has half the time to get the air into the cylinder. The piston is very sorry but say it only gets 75% or 3/4 of the air in at 5000 revs. It will generate 75% of the torque for that piston stroke. But at 5000rpm it it is doing two of these 75% strokes. So the engine produces 2 times 75% power or 150% of the power generated at maximum torque.
Does that explain how torque is related to a specific speed but power is also dependant on the number of revs and the torque figure?
The beauty of a CVT is that at maximum power it will give maximum acceleration because power is what is needed to accelerate the car. A CVT can be confusing because at part throttle and a lot of revs can equal full throttle at less revs - like travelling in 4th or 3rd 30 mph.
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