techathy said:
i haven't got any print out for it for exact numbers but for comparison my son recently had his modified Golf Mk5 Ed 30 rolling roaded , it produced 364 hp / 376ft lbs / 510nm & he's on fwd with standard wheels on 235 40s 
Busterboo said:
when they hit anything other than smooth tarmac 
that unnervving skittishness leaves them intolerable for me . No, for general driving it's not an issue but 275s help going across non-perpendicular badly made/placed road surface joints at high throttle openings. With the tyre pressures being the same, the contact patch will be a very similar size.mr wilks said:
Well, they lasted just under 14k miles before they reached 3.5mm of tread then I got a nasty sidewall laceration. The only reason I went to the PS4s this time is because they stocked the PS4 in the sizes I wanted.mr wilks said:
techathy said:
mr wilks said:Busterboo said:
They didn't feel bad in comfort terms when i had them on my first E89 (23i) they just show their deficiency when trying to enjoy a more spirited drive
Here's one for you to ponder over & may help you accept you are never going to be able to prove your theory right or wrong :wink:
3 E89,s all same spec
1 has 18inch non runflats & covers 6000 miles pa
2 has 19inch non runflats & covers 4000 miles pa
3 has 19inch runflats & covers 3000 miles pa
which one will get a split wheel first ?
Busterboo said:mr wilks said:Busterboo said:
They didn't feel bad in comfort terms when i had them on my first E89 (23i) they just show their deficiency when trying to enjoy a more spirited drive
Here's one for you to ponder over & may help you accept you are never going to be able to prove your theory right or wrong :wink:
3 E89,s all same spec
1 has 18inch non runflats & covers 6000 miles pa
2 has 19inch non runflats & covers 4000 miles pa
3 has 19inch runflats & covers 3000 miles pa
which one will get a split wheel first ?
I don't know. I do know that my 18" 'normal' tyres have done 16,000 miles in the last year (not commuting miles - I drive the car for fun) and ...
1 they drive much, much better than runflats and ...
2 at 37,000 miles to date, the wheels ain't cracked (which, in Leicester, is remarkable).
However, as you say, perhaps they look like saloon wheels & tyres.
In an ideal world, I'd like 19s with non-runflat tyres that drove as well as 18s on non-runflats, but, since you say they drive only as well as 18s on runflats, I have no choice.
you might even be pleasantly surprised 
mr wilks said:... Well if you ever want to try a set of 19s with decent non runflats on your car you are more than welcome to come to Lancs & try my spare set for a drive out
Once you're in the range of the car behaving consistently and in a predicable manner then there's no case of a 'better' suspension setup/tyre size. Rather there are various compromises to be made and BMW have picked on a compromise which is the best balance they feel meets there goals. These goals include increasing fuel economy, satisfying emission regulations and pandering the legal department.mcbutler said:
Well they are much worse than RS3s when it comes driving on snow & slush. I assume this it down to the actual tread pattern of the tyres, the RS3s have those 35 degree dispersion groves across most of the tread, where as the PS4 is an all longitudinal design.mr wilks said:
