I'm presently running stock 245/45/19 with 9" wheels.

I'm thinking about a different set of 9" wheels, and replace the tires at a later date with wider rubber. It'll be a square set-up.

It looks like a 275/40/19 would give me 1.2" more tire patch to the ground and the tire height is identical. Would a this be safe for 9" wheels?

Can I go as high as a 285/40/19?

Safety is primary.

 

in my unedumacated opinion you do not want to go that big up front. it doesn't add any 'safety' but will affect steering and produce unnecessary stress on the front end. if it will even fit on the front. 285's out back on 10" rims are what i currently run with 255's up front. i've seen max 275's up front on 9" rims.

 

Thanks Darren. I'm still toying with the idea of new wheels, but tires will wait. Just planning ahead, but if I can run 275/40/19 square safely I'd consider staying with 9" wheels. I'd like a bit more patch on the asphalt.

 

I run 275/40/19 tires on a 19x9.5 rims!
Fit perfect work great!

 

But I wonder how much difference your extra .5" makes. 275/40 seem ideal if I can feel safe on 9" rims.

As an aside, my ex-wife demanded 9". I told her I wasn't cutting off 2" for anybody.

 

I've seen people put 285s on the back, but typically 255-265 is the widest you'll see on 9" rims up front. 275s fit up front, but I wouldn't want to risk it on a 9" wheel.

 

Many guys are autocross racing on the factory 9" wide brembo wheels with a 275 wide tire, front and rear!

 

Ford and GM put 275/40/17s on the 99-04 Cobras and 94-03 F-Bodies, stock. 275/40/19s are what I'm going with when I replace the daily tires. 275/35/19 would be the same overall diameter as the 255/40/19s, but I want a little taller sidewall for better ride and to fill the wheel wells without actually lowering the car more.