I dont think the VR helps at all when panning.....

That's very good too, but it really depends on what's important to you.
Personally I like your long lens shots taken at obviously higher shutter
speeds better, even though they do not convey the sense of fast movement
that this sort of panning shot does. This is because I'm interested in
seeing the cars as sharp as they can be. I already *know* they go fast, and
don't need the camera to tell me that. But others less interested in the
cars themselves probably will like that kind of panning shot better because
it effectively communicates motion. So there really isn't any "best" way of
doing it as far as I'm concerned.

I like to shoot old aircraft at air shows. There there's a problem with
propellers. Airplanes in flight look all wrong with the prop frozen by high
shutter speeds, so to give a realistic blurred look to the prop arc I have
to use 1/250 or slower -- much slower especially with WW I era planes with
their slow-turning engines. But that's the *only* case where I use slow
shutter speeds deliberately to blur any part of the photo. Events like
motorcycle hill climbs, etc., I want everything sharp. Others may prefer
blur to show motion.

I don't think that's true, but why even worry about it anyway? I think what
you're doing is good already, and will probably get better the more you do
it. As for being "creative" and "really good," whatever those terms mean to
you, as long as such things are important to you they too will probably come
to you the more you work at it. But the desire to be "really good" suggests
that perhaps the opinions of others are more important to you than they need
to be. Do you enjoy what you're doing, and like the results yourself? I'm an
amateur too, and have been for 50+ years. Some of my photographs are "really
good," which simply means I like them a lot. Others like them too, and
praise is always pleasant to have, but I really do this stuff primarily for
my own enjoyment.

Neil

There you go. I believe there's three techniques to use:

1. fast shutter speed to freeze everything and get the sharpest image of
the car, this is the easiest in good light. Personally, a couple of these
tend to be more than enough for me. Of course if you are capturing
something else, such as a wheel in the air over a bump or just due to
cornering forces or crossed up action that's different and much better,
imo.

2. slow shutter, NOT panning the camera, so the background is sharp and the
car/mc is blurred. Be careful here to have a good background here.

3. Slower shutter panning as previously described. And yes, you can and
should use VR here. Always good to have this technique in your pocket, for
when it's just too dark for anything else.

Look for positions which convey the actions of not only the car/mcs, but
the driver/rider if possible. Exits of corners where there is
sliding/crossed up action or even run offs. Can you get close enough and
are conditions such you can focus on the driver/rider in a spot showing the
effort required? Of course passing spots are another thing to look for,
such as this:
http://edwardgruf.com/Digital_Photography/dSLR/VIR400/slides/DSC_0819.html