I don't mean to discourage someone from trying the NASCAR season, just pointing out the very real logistical issues.
If I had the money and a reliable DP with a firm ability to dry camp at the tracks - I'd do it NOW.
One thing I forgot to mention is that race weekends are intense. A lot of activity and action. Not really restful. Just going out to TMS for a fall weekend, staying with a friend located four miles from the track - I needed two days to recover from the weekend. Not getting in the rig to drive near 900 miles to Bristol or 1,100 miles to Phoenix on Monday-Wednesday.
IMHO, now is the time to start gathering information and mapping out a plan for the 2016 season. NASCAR will announce the 2016 schedule in late August 2015. You need to already have the contact information for each track, the budget worked out based on the 2015 costs for tickets and camping and be ready to lock in reservations.
Many tracks will start selling tickets for races a year in advance. Some tracks with two races will only sell tickets and camping after the previous race is completed.
Another option to consider is the XFINITY (Nationwide / Busch) series or the Camping World trucks.
The Trucks might be best because it is only 22 events - 1/3 less than Sprint Cup, and only two races 'out west' - Las Vegas in October and Phoenix in November.
All three series do have the Texas-Phoenix-Homestead final three races.