So what would happen if you reduced the width on Omega's......
?
Ive just gone from 215's to 205's (they didnt have 215's in stock)
Immediate difference i noticed was how much i didnt feel the rough road surface....
I dont thrash the passat......so dunno what the reduced tyre size has done to gripablility
I have been checking the net and discussions about tyre grip as a function of width..
first I'll say my conclusion : on streets and crowded, speed limited motorways where you have low/normal speeds
you can practically assume physics basic friction law to be mostly applicable(with rare exceptions).. so you wont feel a difference between an 205 or 235 tyre.
however, looking at the fuel bills their grip differences are measurable

(also as a function of tyre weight)
now when the time comes to test/measure their lateral g differences at curves with serious speed, the picture changes .. because tyres dont have a static shape and dont behave like static solid friction blocks..
and also when you compare those tyres for drag type usage of course wider tyres will make difference..
but more important than that, the tyre design, tyre temperature , environment temperature , environment surface conditions plays a very critical role which is the mostly ignored factor..
as a basic example compare 2 cars, one having winter tyres with 205 and other car with summer tyres 265 width where surface is snowy/icy and temperatures around 0 celcius.. I think everyone can predict the difference.. ps: I have used 195 , 205,215 and 225 size tyres on omega on a wide speed range .. and I have noticed drive train components like shocks, springs and wishbones effect more than the tyre (assuming the tyre is not a very low quality type