Tyre profiles - yes again. Forward stance?
Discussion
Going to get wheels refurbed and new tyres on the Chimaera in the winter since my rear tyres are 15 y.o..... Thought the grip was a bit iffy.
I've read many threads about wheel and tyre sizes on here and it may seem it's been done to death. The one thing that seems mostly agreed was that a 'stance forward' should be maintained, i.e. the diameter of the rear combination should be 20 mm (ish) more than the front. This gives a 'nose-down' of 12mm or so depending on the tyre wear.
I've seen owner manuals stating anything from 205/60 x 15 to 225 /50 x 15 for the front depending on the year, and 225/55 x 16 to 245/45 x 16 on the rear.
The initial switch down from 205/60 was due to unavailability of Z rated tyres apparently.
However the combination in the owners manual for my recent car is a little strange:
It's a printed date of 1995 for a 1996 car. The 235/50 x 16 suggestion on the rear for the 500 is new to me and a quick search shows it virtually impossible to buy now anyway.
The suggested combination of 205/60 x 15 for the front and 225/50 x 16 for the rear on my 4.0 gives a difference in diameter of only 4mm (!) In fact, if the rears have 2 mm more wear on them (overall 4mm in diameter) than the fronts, the diameter of the front wheels will exceed the rears.
I'm surprised that this recommendation is from the factory. But then again, maybe I shouldn't.
Maybe there is no need for a forward stance after all? Apart from aesthetically. I've seen photos of Chimaera / Griffs with 17" and 18" wheels & the same tyres all round, and they don't look right to me.
I've read many threads about wheel and tyre sizes on here and it may seem it's been done to death. The one thing that seems mostly agreed was that a 'stance forward' should be maintained, i.e. the diameter of the rear combination should be 20 mm (ish) more than the front. This gives a 'nose-down' of 12mm or so depending on the tyre wear.
I've seen owner manuals stating anything from 205/60 x 15 to 225 /50 x 15 for the front depending on the year, and 225/55 x 16 to 245/45 x 16 on the rear.
The initial switch down from 205/60 was due to unavailability of Z rated tyres apparently. However the combination in the owners manual for my recent car is a little strange:
It's a printed date of 1995 for a 1996 car. The 235/50 x 16 suggestion on the rear for the 500 is new to me and a quick search shows it virtually impossible to buy now anyway.
The suggested combination of 205/60 x 15 for the front and 225/50 x 16 for the rear on my 4.0 gives a difference in diameter of only 4mm (!) In fact, if the rears have 2 mm more wear on them (overall 4mm in diameter) than the fronts, the diameter of the front wheels will exceed the rears.
I'm surprised that this recommendation is from the factory. But then again, maybe I shouldn't.
Maybe there is no need for a forward stance after all? Apart from aesthetically. I've seen photos of Chimaera / Griffs with 17" and 18" wheels & the same tyres all round, and they don't look right to me.
ianwayne said:
Maybe there is no need for a forward stance after all?
As you said that has been developed by the forums. It looks nice aesthetically. Aerodynamically I suppose that if the front is higher then there may be an increase in the tendancy for the air to give greater lift to the rear of the car. Maybe. It's nice to see that the original 215/50/15 still got a mention 
ianwayne said:
I used to have a Lotus Excel in the mid 90s and they had 215/50 x 15 tyres. Almost impossible to get hold of by then. The only other car I ever same them on was an Audi Quattro, so was surprised to see them on the spec for 1995.
Honda NSX as well if my memory is correct. I think that the factory only fitted them for a year on the Griff - it was just nice to see them mentioned in 1995/96 Gassing Station | Chimaera | Top of Page | What's New | My Stuff