Originally posted by griphon:
When i play with no music the sound of the car is very funny not like that of a downhill run. It sounds more low pitch even if i drag a gear.
This is pretty normal since the track affects your gearing. If you are going uphill, you'll need to drag a little bit longer at the lower gears to build up power before you can shift to a higher gear. If you are going downhill, it'll be the opposite. If you use Iro (last track) as an example, when going uphill or downhill, you can see the difference in gearing.
When you hear the engine giving out a high pitch whine, that's the signal to change to a higher gear. But you should do it before this high pitch whine.