You can also make the original wheels bigger, then you get this: I didn't make the wheels fit very nice, but you got the idea! Here you have some better results!
Oh? I never saw that tut. I saw these cars on Google and I tried how to make something like that and thats how I got it...
or you just found it on www.good-tutorials.com ( the tut is there also ) but I dont care m8 gl with it