Hey guys on standard cars you get from the UCD the lower the mileage the car the more hp u will get after an oil change and engine rebuild. I have 5+ Honda crx's all with different mileage, and all have different hp from 309 to 322.. lower the miles the more hp you get. Even if u buy a car with high miliage and rebuild the motor at gt auto it still won't have the hp the same car with less miles has. If you bought the first two rounds od DLC however PD gave you a reward and issued us with a WHOLE car refresh( to get these tickets u must go to your items list and select it from there, it's the only way and kinda hidden) which will set miles back to 0 and then you will have to put 181.7 miles back on it to full break it in and get MaX hp. Typicaly a car with under 4km total mileage on it will be a great buy because you will get the benifeits of low mileage hp with out having to break it in, jus give it an oil change and ER and your golden...on cars with 4km or higher mileage you start losing increments of power from that point on.... Hope that didn't confuse anyone lol. If you need more proof just buy several of the same exact car when they pop up in the UCD and compare miliage/hp.....