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.

I agree with Rob> 2 hours plus, especially if transferring to terminal #2