As per title really, I've always been curios about why the seats in production derived racing cars are so low. I've always though it was for weight distibution, is this the case or is there something more too it?

Just to get the weight as low as possible which lowers the roll centre which improves the handling

In the normal world (as in sticking one in a chavmobile) does having your 120kg an extra 4 inches lower make enough difference to be significant?

And it gets your head further away from the tarmac when you're upside down!

W

Assuming a driver weight of 75kg that's still 5% of a 1500kg car or 7.5% of a 1000kg car. In relation to what else you can relocate to affect weight distribution that's a big chunk! I know in my 600kg Indy it always felt better (if less willing) with 2 up.

Gives you more room to get a skid lid in for a start.

I always find it feels more sporty sitting lower down in the car... I can pretend the bonnet on my polo is 3 meters long with a supercharger v10 under it from that angle :p

Thanks for the replies, so to clarify it's mostly a weight thing but there are a few other advantages.