Hi there-
Yes, when you take the practice tests, it will give you the option to take the test entirely untimed. Just be aware, though, that this will make your score much less reliable than if it were timed. Timing is such a huge part of the GMAT and your ultimate score, that there's no to accurately predict your score with an untimed test. That being said, the option is still available to you if you still want to take an untimed test.
Best,
Brie Truesdell
Student Services Associate
800-576-4628
studentservices@manhattangmat.com
www.manhattangmat.com