Pulleys interchangeable?

[Swing]

Ok thanks. Could be because of simply different width of the pulley and length of the bolts,.

Originally Posted by WeeYari

If only that were true.

It is not really a matter of consuming less power. The light weight achieves that. Going 10% underdrive was a way of making the pulley lighter still, while still providing enough rotation to drive a/c, alt, and water pump.

But if it's 10% smaller then it's like a 10% smaller gear. It means that for every revolution of the engine, the waterpump will drive 10% less, costing 10% less energy. The alternator is a different story, I guess the same for a/c if you have it. The alternator will have a certain load to generate a certain amount of current, so that will always be the same amount of resistance.

So why wouldn't underdriving work? Of course I could also put a bigger pulley on the waterpump (might be easier to find) to have the same effect.

Of course, the lightweight idea is straightforward and clear.

[CTScott]

Originally Posted by Swing

Ok thanks. Could be because of simply different width of the pulley and length of the bolts,.

It could be that or it could be that they are different diameter bolts. Unfortunately I don't have enough detail on them to be able to tell. You could go you your local parts department and have them pull the three different MK1 Yaris crank pulley bolts to see the difference. Over here we just get the 1NZ, so we don't have access to the others.