Maybe I should re-upload it with some more info, but then again I kinda don't want to because some events, but then again I kinda would like to, maybe some day. Just note that finding out RPM from sample is not 100% certain, sometime it works, sometimes it does not, also my sound tutorial thread has posts by other members which might help you more.
That is kind of thing everyone would like to know, it might be that such does not exists at all, but if you ever find such magical place, tell about it to others too. There are places where you can get free samples, but none has anything that would work, afaik. Many guys try to get something from YT videos, with varying success, but most of the time it is hopeless. Even self recorded samples are often poor quality, because of recording device or interfering noise. It is like trying to find textures for 3D model you just made, while samples might be bit easier, there really is not much of them floating around, especially legal ones. It has been so since beginning of car games really and beginning of modding.