Marc, per my calculations the new tire is about a half inch taller than the old ones. Any time you increase the overall diameter of a tire from stock it will change your final drive ratio. In your case with installing larger diameter tires it would be like installing a lower (numerically) rear-end gears which will make your engine turn slower at any given speed.

Having said all that junk, I doubt you will see a decrease in acceleration and at most your speedometer might read a mile or two slower than your actual speed. After all, what's a half inch between friends and tires