http://www.ludegeneration.co.uk/wiki/in ... Tyre_Sizes
I have always run 16" wheels with 205/50/16 or 205/5516 tyres on them.
Most people are running 17" wheels these days.
Intake - ive tried a few and the oem type S intake is what ive settled for - i would stay away from the ebay induction kits

if you were going on track a long arm intake with cone filter and maybe some sort of air feed from the front of the car would be what your looking for..there are some long arm intakes that have a water bypass valve fitted or you put a rain sock over the cone filter.