Required (Necessary) Layover Time in Mexico City

Coming from the US and needing to go through Immigration in Mexico City, how much time between flights is usually necessary? Looking at several options, many layovers are only 1:15 to 1:30. Is this sufficient time?

Thank you.

Rob

As someone who has literally run from one end of the Mexico City airport to another to catch a plane, yes. But it can be tight if it's high tourist season and there's a crowd. Two hours would be ideal.

It all depends how many planes hit the international terminal at about the same time. I've had the line backed up to the top of the stairs and other times there was basically no wait. No way to know ahead of time.