I play online here and I think your question has a 2 part answer.
1. Yes some players use cheats online.
2. Your car will get better as you unlock more in the game and upgrade it when you have won a few races.
Edit: Btw, I am currently playing thps4, nfsu, and working on increasing my online game collection. I plan to buy about 2 new games a week. Gotta find out whats good though. I have a thread I started in the Off Topic forum about seeing if anyone can post some good online games for me to buy. Feel free to throw some of your favorites on it if you get time. Thanks
