and here's the bit about the tyre size he told me about
"To answer "what am I doing to the car ?" then in short, you are chasing away good handling in favour of more grip and "looks". Think of it as a bowler - handling is the ability to bend the ball via spin, making the ball do exactly as you want. Grip is simply bowling as fast as you can - you cannot do both. An Omega B needs 195-section tyres, no more. At that point, the car handles excellently, giving you the best control. This is indeed what the chassis was designed with ( Carlton ). Since then, the fashion has been to ever bigger wheels. To these, you need to fit low profile tyres to keep to the same wrpm. But, this hurts the comfort and handling.
An Omega B on 235s is actually quite over-tyred - something you can tell when driving, especially at the front. I'm currently running my MV6 on 195 snow tyres and it's an absolute hoot to drive. Its certainly no faster on 235s and I wouldn't say it handles any better, either.
As another comparison, I'm running just over 400 hp in the Holden, on 245's all round. Even at that power level, I'd still say its over-tyred.
hope this all helps..... ( you can post it if you want )"
HTH
Matthew