Hey guys i have aftermarket rims, first owner had 275 30 20 on the rear but I need to replace them . Would a 275 40 20 tire size fit the same rim and not rub against the car , what size would you recommend for 20 inch tires ?

 

Depends on how much clearance you had between the tire and body with the 275/30. But I'm pretty sure a 275/40 would fit no problem

 

Keep in mind your speedo is going to be off with a taller tire

 

OP you seem new to the G and that's cool, we've all been there. What you need to know about the tires is the rolling diameter F/R needs to be within 3% of each other to keep the VDC happy. So you'll need to know the size of your front tires first to determine what size rear tire/s will work.

There's a great wheel/tire calculator in this link. http://www.miata.net/garage/tirecalcold.html

So using it, if your front tires are say 245/35/20 the diameter is 26.8". A 275/40/20 is 28.7" which is 1.9" or 6.6% different which will freak out your VDC and send your car into limp mode. A 275/35/20 would be 2.9% different which is pushing the 3% target so if you want to keep 275 as your width the 30 series is your best bet. If you want more sidewall a 265/35/20 would be .3" taller and the diameter difference would only be 1.9%

Hope this helps and doesn't confuse the hell out of you.

 

What Tim just told you was No you can't run 40 series tires with your 20" rims, stay with the 30 series....Gary

 

Depends on if your lowered. I was lowered an inch and a half with 19's and I rubbed with a 35 sidewall.

 

Hi Gary, I'm new here had a question, can I run 275/35/20 rear, 245/35/20 front? I really want 35 up front for a smoother ride, I will be Rollin fenders, thanks

 

Hi i'm new here too i just bought a 20x8.5 inch rims whats the best tire size on the front and rear, one of the tire guy i saw said i can roll a 255/40 in the front but im not sure if his right please help me here thanks