Currently I have V rated tires on my Honda Accord (which is a V6). If I go down to an H rated tire, would that be bad for my car? Should I stick with the V rated tire?

V-rated tires have a higher speed rating than the H-rated; you don't need to stick with the V although it is a slightly better quality tire than the H.

Thank you this8384 :)

Any time :)

Modern cars are often designed to use a particular tire type. Suspension, braking, and steering performance may be adversely affected by changing to a differently rated tire. "Today, automobile manufacturers program into the onboard car's computer system critical tire data, such as height and rolling resistance. Tires are designed as a very intricate part of the vehicle. Much like the fender for a 2003 Buick Park Ave is the only fender that will fit and work correctly; tires are treated with the same care and design. What the manufacturer equipped the car with, in both size and performance rating is what should always be put back on. Failure to do so can result in erratic handling of the vehicle, a check engine light on or worse yet and accident."


Source:
http://expertpages.com/news/performance_tires.htm