So I have the ever-so-rare Ronaele Cobra III rims on my car, 9" wide in front and 10.5" wide in back (I think). For years I have been running 255/35/20 all around. Well I need to get some new tires and I was considering going wide in the rear tires, ie. 275/35/20. Just curious what difference wider tires makes in grip, ride comfort, and overall look? Can I get some opinions on this please?

 

After having the stock all season p-zero nero all season then going through 255/40/19 and 295/30/20 pilot supersports, and now on 275's and 305's in tires I would say they help in cornering a good amount, you can apply more throttle in corners earlier and have a higher corner speed. With the stagger i would say also its harder to lose control. As for launching from a stand still, even with 305's , on most street surfaces it wont really pull a good launch. On a good street in hot weather it will hook nice though. The looks alone are worth it though imo

On a 10.5 rear , i think a 255 is below minimum width, you should go 295 or 305

 

In a straight line, width means very little compared to compound.

 

How can i tell what the exact width of the wheel is? I bought them quite some time ago, and they don't make them any more.

What's the widest I can go? any brand you would recommend?

thanks

 

A wider tire TYPICALLY means more bite but tire compound trumps width. A wider tire tends to also be more stable but can increase steering effort. With a 20" rim, you'll lose ride comfort compared to an smaller diameter wheel due to the decreased sidewall height (less absorption). Also, wider tires tend to weigh more as do 20" wheels so there's a performance (power) loss there.

I wouldn't go wider than 255's up front. Tramlining becomes significant as you go wider up front. With a 10.5" wheel out back, you could probably fit a tire wide enough to rub so I'd probably go no wider than a 305 although I'm not sure what the actual width is for a 20" tire in 305 and if it'll rub.I'd be checking what I can fit on a 10.5" wide wheel, both min and max, and then see what's available. IMO, I think a 295 would be about it.

 

Your wheels are 20x9 front and rear which is why you have the same tire size on both. You could go to a 265 in the rear if you want but I would not push it any farther than that.

 

You sure about the width? Is there any way for me to check?

So you think 275 would be too much?


Thanks everyone for the input.

 

this calculator is fun to play with and offers limited advice too...just plug your numbers in...

CLICK HERE

 

Most rims have the size in raised print on the back side...along with other safety info...at least many I have had were like that.

 

Ya, pretty sure since I found the original forum thread from the guy you got them from.