Cars generally don't matter, if anything, a Porsche or similar car can be a negative to some women. When I had my beautiful Pacific Blue 911SC 20 years ago, I briefly dated a chick who asked me if I cruise around picking up women in my car. I told her that I didn't need a car to pick up women.
What else was I going to say? It's such a stupid question.
That said, I've always liked the cars a lot more than the image they project. Of course there are exceptions...some women might find a car to be beautiful and appreciate it as an object. And once they get to know you, it really should not matter. I have a woman friend, 40 y.o. divorced and a knock-out who drives a 993 coupe when she is not driving her Toyota PU. The 993 was a gift from her brother when he moved back to Australia...nice brother!