wheels and handling???

[motormadJ]

y is the handling better on a car with 15s n a large profile tyre, than 16s with a low pro... ie the overall size/circumferance etc is the same??? [when they are both lowered]

 

[edde]

There just less roll doesn't make it any better I'd argue I'd prefere 15's all the time smoother ride (cheaper tyres is also good). If the 16's were the be all then why do the race cars run 15's

 

[GordonD]

y is the handling better on a car with 15s n a large profile tyre, than 16s with a low pro... ie the overall size/circumferance etc is the same??? [when they are both lowered]

The ride would be better on rough surfaces with 15" wheels because of the taller more-flexible sidewall, plus the wheel and tyre combination would be lighter, reducing unsprung weight.

But I'm not sure that most people would agree that the handling was better. Handling wouldn't be as sharp with a 15" wheel because the taller sidewall would flex more. And grip wouldn't be as good because, even if its the same nominal width tyre, a lower profile tyre puts more rubber on the road.

As to why they run the 15" wheels on the race cars, the benefit of bigger diameter wheels is fitting bigger brakes, and the disadvantage of bigger diameter wheels is that they're heavier, cost more and there's not as good a range of tyres available, so if you're running a class that's based on standard cars and requires running standard brakes there's not a lot of point in choosing larger wheels.

 

[CJ]

y is the handling better on a car with 15s n a large profile tyre, than 16s with a low pro... ie the overall size/circumferance etc is the same??? [when they are both lowered]

But I'm not sure that most people would agree that the handling was better. Handling wouldn't be as sharp with a 15" wheel because the taller sidewall would flex more.

If the psi is the same, wouldn't the flex be the same (in theory)

 

[Englebert]

That would suggest that tyres are filled with so much air to the point they are rock solid, which they aren't obviously.

 

[White16valver]

Don't confuse grip with handling!

Lower profile tyres = less sidewall flex = stiffer ride and quicker transfer of cornering forces

higher profile tyres = more sidewall flex = more comfortable ride and more gradual transfer of cornering forces

Increased grip through the use of larger wheels (both diameter and width) means that breakaway on the limit is snappier. Running 15s on a 185/55 like on the valvers and williams means that grip is still good but it's not snappy on-limit, so you can just play

 

[motormadJ]

cool. thanks