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KnifeEdge_2K1
07-06-2004, 03:07 PM
does any one know of a rule for what's the best tire size for a car of any given size?

generally the larger the tires (width wise) and lower the profile the more grip it has but at some point the advantages no longer outweigh the disadvantages

is there a general rule for this?

also i believe that there is an ideal ratio between diameter of a tire and it's tread width. for my calculation purposes i use 0.4

this is because if there was a hypothetically some tire that is 255/35 but on 15 inch wheels ... thats gonna be pretty damn bad

just as 200/50 tires on 18 inch wheels would be pretty crappy as whell

fpv_gtho
07-06-2004, 08:38 PM
Alot of things can affect the tyres: What drive, what power and torque, the dimensions of the car etc. For instance, my dads 66 Impala has 265/50R16's i think and they really look the part. On the other side of car dimensions though, ive seen Datsun 1200 coupes with 205/70R13's and they also look the part.

Matra et Alpine
07-07-2004, 03:51 AM
does any one know of a rule for what's the best tire size for a car of any given size?
There is no hard and fast 'rule' for all cars.

There is lots of gotchas, maybes and don'ts though :)

Suspension - wider tyres can cause odd behaviour if the suspension varies camber significantly during suspension movement. If the car starts with lots of camber then wider tyres can cause odd handling as one tyre wall ends up with most of the weight and you can scrub tyres VERY quickly.

Steering, wider fronts can start to induce significant bump steer if the point of contact is moved to far away from the 'ideal'. It is often necessary to increase offset on fronts to avoid rubbing on inner wings. This thenmoves the point of contact out and alters the steering geometry.

Weight - wide tyres with a lot of weight don't manage to scrub well and can cause tyre distortion on cornering. This knackers the sidewalls.

Best option is to find car club of the model you're interested in and ask advice.
There will always be someone who has tried to go one size too high and can tell of the horrors and the size they then dropped back to :)

KnifeEdge_2K1
07-07-2004, 08:06 PM
wow i always thought there was an ideal size for a car, obviously a bigger car requires bigger wheels but as i said b4 i thought that there was a tread width/diameter ratio which resulted in optimum performance.

thank you for your insight guys, just a laugh though i saw a civic at summer school today with what i can only guess are 19 or 20 inch chrome wheels on the back with the stock wheels up front ... funniest thing i ever saw

KnifeEdge_2K1
07-15-2004, 07:31 PM
your life must be very dull, if that is the FUNNIEST

dude its an expression ...