I got into Michigan's LSA Honors Program with a 4.22 weighted, 3.66 unweighted with a heavy course load. I'm OOS and from a school that receives a pretty good amount of acceptances from Michigan.
If there's a chance that you'd be fine with going to Michigan as a non-preadmit to Ross, I wouldn't apply as one... this is just a theory, but I feel like Michigan doesn't want just all "Pre-Ross" applicants, so they try to look for kids who have other interests. So by applying as a pre-admit, you'd be competing with a higher and more qualified pool of kids since you'd be marked as an "intended Business Major," something Michigan has a LOT of. Like I said, this is just my theory when it comes to applying and getting in. But if you really want to go to UMich and not just for Ross, it might help you.