handling improvements

[bbautox]

I have 14 inch tires and looking at increasing to 15 inch.

also looking at going from 70R to 60R?

Is this Ok to do? or will I regret it?

[mrr23]

for better cornering, you want a short sidewall. 14" doesn't give you much choice in that area. 15", 16", 17" etc... give you more choices. the downside is you feel more of the road irregularities.

[Eugenio_SS]

for better cornering, you want a short sidewall. 14" doesn't give you much choice in that area. 15", 16", 17" etc... give you more choices. the downside is you feel more of the road irregularities.
not really... given the same construction, you are better off getting as much sidewall as you can get... look @ F1 tires... huge sidewall, btw.
for better performance, get the widest, smallest diameter, as long as it clears the calipers.
Most people prefer the 16x10s over the 17x11s for performance reasons... not only one gets more sidewall to make the tire work, but also reduce weight on rotation, which is a blessing.
Good luck.

[mbraun]

I run 275 40 17 on front and back. it works good for handling. remember that our cars weigh a ton more than an F1 car so side wall flex is a real problem

[Eugenio_SS]

I run 275 40 17 on front and back. it works good for handling. remember that our cars weigh a ton more than an F1 car so side wall flex is a real problem
I know... and that's why we need width... i have 315s on all corners.

[mbraun]

Additionally if you look at the construction of tires for high end race cars like nascar you see that they are limited to 15 inch rims and have large sidewall. The reason for this is that they are run flat tires. basically they have a tire inside of a tire so that they can minimize crashes due to a flat.