[ceejayoz]

I think you're mixing up Falcon Heavy / Crew Dragon with the proposed 2018 Mars mission, "Red Dragon" (which will probably launched by a Falcon Heavy, but will involve a heavily modified Dragon v2). My understanding is we won't have any details on Red Dragon until September.

[BrandonMarc]

The "Red Dragon" mission will indeed involve a Falcon Heavy and a modified Crew Dragon, craft which are mostly complete and will be tested in the near future.

The September announcement at the International Astronautical Congress will be their full proposal for sending humans to Mars, including BFR, MCT, ISRU, the whole works.

For more info, check out the SpaceX forum on Reddit. I know Reddit has a reputation, but the SpaceX fans run a top-notch community there.

https://www.reddit.com/r/spacex