I am a rally car driver. If you go into any restaurant in LA and ask your waitress what her career is, she will certainly tell you she is an actress. She's just doing this gig between roles.
If you want to be successful, you have to tell yourself and others what you are. About two years ago, I stopped telling people I was a designer and started saying I was a race car driver.
I put more time into racing (car prep, marketing, travel, meetings, chasing down parts, keeping sponsors happy, and a little bit of actually driving) than I do on my day job. It is beginning to pay off.
On Monday thru Friday from 8-5, I do contract work for Ford Design. I'm pretty much relegated to computer modelling in Alias now. Contrary to popular belief, my Ford ties had and have absolutely nothing to do with my Mazda ties.
If you want to be a rally car driver, be one. If you want to be a guy who rallies for fun, that is just fine, too. I believe your success will be relative to either the time, or the money (or both) you put into it (depending on how you measure success).