Pittsburgh Vintage Grand Prix

Is it just me or does the blurred car in the back suggest a larger

distance between the two that there actually is ? I wasn't expecting

that tracking motion mostly towards me would produce quite this effect.

It still looks close to me. You must have had very shallow depth of field. Usually when the cars are this close the one behind will be mostly in focus.

Some if it is down to DOF, but some of it is because the the two cars weren't moving the exact same direction and I was folloing the front one

Not bad. I actually quite like this as it is a little bit different and quirky.

 

HOWEVER, the shutter speed you've used (1/60) is way too slow if you want to be shooting this sort of action to any reasonable sort of standard and consistency. With slow shutter speeds, any lateral or vertical movement of the subject(s) will be accentuated, and that is why the following car is blurry.

 

For head on action, you need to be using at least 1/400 and in most instances faster than that depending on the light conditions and the ISO rating of your sensor.