Is 1h 48m enough to clear customs at IAH?

I'm currently planning a trip to Europe and the best schedule and route I've found has a 1 hour and 48 minutes layover at IAH. Thing is I'm not an US citizen and the previous flight starts from outside the USA, so as far as I know, even though I'm just at that airport for a connecting flight I still have to go through migration and customs before running to the connecting flight. I've never been on the Houston airport, so I have no idea if less than 2 hours is enough to do this. I've waited up to 3 hours on peak travel season on MIA airport, so this makes me hesitant to purchase a ticket with so little time in between flights. For reference this trip would be in late September and between 4pm and 5pm with the departing flight being the one to Frankfurt. Any insights will be appreciated!