I still have standard wheels on my Q4 and looking for going for something bigger..
For those who know the issue...what's the best way to go??
Your advise will be welcome and appreciated!
A subject that has been going through my mind recently. The 16" wheels I had on my 2.0 16v Sportpack 205/45 ZR16 seemed more than enough grip for FWD. I was thinking of running the same on the Q4, once the current tyres are through. that should be 1 or 2 tracks days
Q4 s standart tire size is 205/50/15 or wide body 205/45/16 ,
if you want to bigger than ,best option is 205/45/16 .
Because 155 hasnt got large rim-tire space ,if you trying 225 tire posible have problem (Im try ) .
Otherwise best second option is 215/40/17 but this tire %3 bigger than old .When goes 240 km speed ,your odometer show you 232 km !
Rim size is 7X16 ET35 is good (4 X 98 hole is must ).
And last ,please choose W or Z series tire ,if your car already Rocket
Thanks, will change to these next time I think, the noise is the normal noise you would get when pushing a car too hard round a corner, more of a screech actually, I think its less now with this afternoons work
Of this handful of alternatives discussed I'm not sure all of them have LOAD INDEX high enough to cary the weight of the Q4. 1465 kg without driver and 61% weight on front wheels gives at least 450 kg per front wheel. That is a lot. I use both 205/45-16 on 7x16 rim and 215/40-17 on 7,5x17 rim. Both of them work fine even though the larger one may touch some of the plastic details at maximum steering. Anyway, I would recommend the 205/45-16 standard size wheels on most roads.
But, just an interesting detail, Kumho ECSTA V70A in 205 width is 10 mm wider than the 215 width Michelin!!! That means more rubber against the tarmac and still better ride comfort. On the other hand is the Kumho tyre a racing tyre and not recommendable for road use. But I consider it as the best choice for track use in the hardest compound. The softets one, which I tried first, was of 50 Sure hardness which could be compared to the softest Michelin road tyre which is of 220 Shure hardness. The softest Kumho compound overheats before the end of a long corner
The 205/40x17 BFGoodrich tyres I'm using are the extra load version which has a load index of 84 compared to the standard Michelin Exalto's 205/50x15 that had a load rating of 86 which I thought wasn't too bad a drop....
The pressures you mentioned seemed to be the wrong way round and also a little low..
You should be running around 36psi (2.4bar) at the front and 33psi (2.1bar) at the rear. Remember that you need a higher pressure at the front since this is where you carry more weight. Also, a higher pressure at the back may induce oversteer and increased wear in the middle of the tyre. You should check tyre load indexes between the ones you have now and the original P-Zero tyres (205/45-16"). If the load indexes are different, you have to adjust pressures accordingly.