2016 Camaro Interior Room
 

So..... I sat in a 2015 Cadillac ATS, with and with out a sunroof. It's on the same chassis as the new Camaro. Anyway, the seats are narrow, no headroom for a helmet with the sunroof and marginal without. The 2015 Cadillac CTS is a bit better but I think its a different chassis? Any less room than the current Camaro is a problem for me as my race helmet just clears!

The Camaro might have lower seating position or design features for additional clearance. Also the gen 5 does have that much room either a lot of people complain, you just have to adjust your seat differently while on the track. I'm 6-4 fore reference.

Both cars share the same platform, just both are modified for their particular application. Also of note the alpha platform for the camaro is 70% unique to the car. So comparison of the ATS and CTS should be taken with a grain of salt.

A sunroof is going to cost you ~1.5 inches of headroom in pretty much any car. Fortunately, there's no way GM will make a sunroof mandatory in the new Camaro. Opt out on the sunroof.

The Camaro prototypes don't look particularly tall, so the ATS is probably a fairly good guide for headroom. If you don't like the headroom in the moonroof-less ATS, you might have a problem...

The 6th gen is shown to have a more prominent double bubble roof design that is not present on the ATS, just some interesting tidbit to consider.