I guess it depends on whether or not the limiter is rpms or speed calculation. When you have bigger ABS "Pinion Factor" programmed than actual tires your speedometer will show faster than actual speed. So if the speed calculation is what the limiter is based on then it would actually lower actual top speed. Of course that is just my observation, don't really know. I did not have a place to test that theory when mine was still programmed for 315s and I put the 285s on.