Woh!!!! Brutale. Seriously, that's one of these time where I find something interesting, for a reference. I'm loving your pics man, how you edited them and the old effect. Cars and background are a perfect combination, and color/levels treatment are fine too. Contrast is very difficult to set in that kind of photos imo. A good control (Selfcontrol) when you are setting up them is needed to give the exact amount. A different shot need a different setting such as Hondas and first 2cv with that touch of excesive brightness, that creates "this", the old look.
But, some angles could be a bit better imo. In other words, there are shapes cutted and composition with a diffused distribution. In some shot could generate a great "casual" looking, but in other seems careless. A balance between both and experimenting is good. That's I really think, you must do what you like lol.
Another thing. In first Honda, you tried to add some dust to edges pic. There is a fabulous idea, but I recommend you using a set of brushes. You'll find a lot of them that gives a very interesting and photorealistic effect.
I'd remember pics from Moglet (I think) also with a subtle circles texture and dust addons. It was so great looking... You'd take a look if you like.
Sorry, that's my first "tochopost" here, as they are called in old Spanish GT forum. But really, I was waiting for something like this, and shocked me.
For my personal liking, I get 1st and 2nd TWOcv for me. First the most, even with a cutted car
Salu2.alexwrc