Montoya's move back to IndyCar after a seven-year NASCAR career was confirmed late last season.
Dixon said that he expects Montoya to need some time to readjust, but that the increase in pre-season testing will help the Colombian to be up to speed in time for the first race in St Petersburg.
"He's won in every kind of formula that he's ever been in," said Dixon. "It's going to be a learning curve, but it's not something that he's not done before.
"Yes, the past six or seven years have been a totally different kind of car, but this year with some of the changes in testing, it's opened it up a bit. There's 18 days in total now, which seems like more than what we've had recently.
"That's good for him, but the addition of being in a really strong team and having really strong team-mates [Helio Castroneves and Will Power] will definitely quicken that process up.
"Say he comes in a little slow; it won't take long [to get up to pace] if he does. I expect him to be quick straight out of the box and having the possibility of going for race wins straight on."
Both Dixon's Ganassi team and Penske will have their full complement of drivers on hand for Friday's Chevrolet manufacturer test at Sebring. AUTOSPORT.com