The best and fastest motor????? No such thing. It all depends on your application, what you are going to use the car for and what battery setup you are going to run.

If you want quality motor then have a look at NEU motors. IMO the best in the industry and they huge range of sizes and winds to suit any application. You can get them through RC-Monster and Castle Creations.

Castle creations also sell a couple of 1/8th motors that are NEU licensed design. They have 1512 1Y 2650kv and 1515 1Y 2200kv motors which are probably the most commonly used in 1/8th cars. I have many of the 1515 1Y and few of the 1512 1Y in my collection. Quality motor and gobs of power.

Everything depends on your application. Give us some specs and maybe someone on here can point you in the right direction.