Exact timing really varies person to person and 1000 different factors. But as a standard bet, Cialis takes just a bit longer to get into the system, I'd give it a good 2-3 hours for maximum effects. Cialis can last up to 36 hours, I swear I've had it last even longer. Its still there to some degree 48-60 hours. So you will have no problem taking it early in the day and it still being good by the end.
Also cialis is good to help with a second round. Doesn't mean it will necessarily get you from needing a day refractory to being able to go right away, but it will improve whatever you have.