How do you know which tyres width should be on the alloys? I've got 2 sets of the phase 2 alloys and across the years I've had 225's and 235's and cannot remember if it made any difference. Is there a marking on the alloys to say what width? Thanks Dan
this is something I've always wondered, then I did a test on the same track. With 225/40 R18 Michelin Pilot Sport Cup had better acceleration but very little grip, but I do not know if this depends on the type of rubber. The same track but with Toyo R888 235/40 R18 car is a bit slower to rise speed but much more grip and I improved time of 2 seconds per lap. Road with 225/40 R18 car is more fun
How fresh were those Cups? We used to race on them in the Porsche Club Championship, they were the control tyre for several seasons. It was at a time widely regarded to be the fastest track tyre but my word I found them very difficult tyres to get on with, they take several laps to come in during which oversteer on corner entry was always a risk, the car always feels really lively like your sliding around all over the place then they overheat and go off after about 20 mins. My fellow racers loved em for those reasons as they made the racing more difficult and lively. Personally I also loved driving on them as they took all the understeer out of my car due to how sharp they made the front end, I had a fantastic race on them back in 2011 in front of big crowds at Silverstone on the Britcar 24hr weekend as seen here: https://youtu.be/O5EQHaLWZJo (shame you can't see them though). Terrifying in the wet though those tyres. Personally I would choose between 225 and 235 on an 8" rim based on how wide the real tyre is, the track tyres are usually 1cm or so wider than road tyres across the tread i.e. a 225 track tyre is normally about the same width as a 235 road tyre. There is some variation between manufacturers.
Hello NJH, the Michelin Pilot Sport Cup were older than 3 years, the car actually had more oversteer. In your experience on the track is better 225 or 235? Always in your opinion the 235 is better the alloy wheel 8-inch or 8.5? Hello.
I don't know with respect to the Megane but I have run 225x50-16, 245x45-16 & 225x45-16 tyres on the same 16x8 wheels on my 944 race car. The wider tyres definitely produce more grip but the car moves around more on them so I was never really convinced that the car ends up being faster over all. Looking at track records seems to back this assertion up as all 3 of those tyre sizes hold the lap record for that car on various tracks thus not providing a clearly superior tyre size option. Personally I preferred how my 944 felt running 225 up front and 245 on the back on 16x8 rims all round (used by a friend for 2 of the lap records I believe) but this means one can't rotate the wheels front to back which is a real issue on track cars as one would always like to wear through a set of 4 tyres evenly. On a FWD car I would definitely run the same size all round but my feeling from driving my stock R26 at Thruxton is I would prefer it on a nice solid tyre that doesn't move around so either 225 wide Cup 2 or Dunlop DZ03g. For the same reason I think it would feel fantastic on slicks. BTW more oversteer seems to be a very common trait on the Cups, especially early on as the tyres take a long time to come in, 3 to 4 laps I reckon. The Dunlops conversely only seem to need one lap then there good for flat out lapping for a good 20 to 25 minutes.
Sorry no I have an R26 which is completely stock expect for it now has an RS Tuning remap. I drove it on track in completely original type specification so Michelin PS2 235x40-18 95 load tyres.
