they have types out now that can last u 5k and 7500miles, but i would never really recommend going more than 3000-3500 in a car that gets beat on and definitely no more than 3000 in a turbo charged car. pending your setup, and whether your turbo is oil cooled or not, it will break your oil down pretty well, just think how frothy and hot it gets being spun around in the turbo.

newer cars can run 4500 miles on oil changes and such if theyre daily drivers that don't experience alot of abuse. i still am sketchy on that but it seems to work. i'm not one to chance it on a junkyard sr motor or KA's that are 100k+ miles or 10 years or older (by now, every year 240 is 10 years old except the 2800 or so 1998 models roaming around).