what diffrence would I be able to see between these 2 tires. I'm trying to decide weather I won't 275/40/18 on some new 18x8 rims I'm getting next month. Which should I go wit, will the 275 have more beef, and look bigger?

 

dude... tire rack, read tire specs and their tutorial. Wikipedia, read the article for tire sizing. These are things you really need to learn about. It's stupid simple concepts... please take the time and educate yourself like we all have.

http://en.wikipedia.org/wiki/Tire_code