Im sorry this is in the wrong forum, but i did not see any forum about tires.

i was wondering what all the different tire numbers and stuff meen. (like P235/60R15) I need some new front tires and i figured i might as well replace the back ones too. Right now my car has the stock Pontiac Wheels and the front has the stock tire sizes. My back however are P235/60R15's and they look SO much better than my front ones.

So, i wanted to know what all the numbers meen, can i get wider tires than i already have (while still using same wheels) and what are some good ones (or sizes) you guys prefer?

I went to Jegs and Summit and looked thru all the tires, they carried none of my stock tire size, but they had a few P235/60R15's.

Thanks.

 

235 is the height of the tire in mm
60 is the width as a percentage of that 235
R means its a radial tire
15 means its for a 15" rim



correct me if i'm wrong

 

i was just gunna ask the same question on how all the tire stuff works, is 40 considered?

 

considered wide. sorry

 

im nt sure, but my old 205/65/r15 were taller but skinnier than my new 235/60/r15, i dont understand tire sizing, but i though the 205, 235 was width and the 60, 65 was height

 

Do yourself a favor and look at www.tirerack.com and they will have all the info you need. Also you can compare sizes, brands and prices. A much better source then Jegs / Summit in my opinion.

 

rofl... VERY close - actually its:

245/50/16 (the minimum you should really have )

245 - Width in millimeters (more is better)
50 - aspect ratio vs width (basically, a smaller number = lower profile)
16 - The wheel size used. 16" rim here.

For 15's, stock is 215/65/15 - a 255/50/16 is almost the same tire height! I love my new IROC rims

If you want to stick, go with at least a 235 width, in whatever tire you use!

 

You want a tire with overall diameter between 25.7" and 26.1". most 15 " tires run the 26.1" (7" wide rims) tires, the sporter f-bodies run 16" rims with 25.7" (8" wide rims) tires. Go on Tirerack, imput the tire size you want, and then go to its "spec" page for tire dementions.

Pics of my tire shop in my garage Those are Firestone SZ50Ep runflats for one of the Vettes on the left, and the "new design" Goodyear F1 GS-D3's 245/50YR16 going on the Camaro

 

so would 255/50/15's fit on the stock 15" wheels?

I went to tire track and put in my car model and year, and they are only showing me 205/65/15's

I just need to know whats the largest width i can go with that will fit. It would suck to order some tires that were too big

 

The biggest I'd dare try would be 245/60/15.

If you do it by car/year, it only lists stock size.

I'd recommend 235/60/15 or 245/60/15s

 

yeah, i was figuring goign with 235/60's because i already have those in the back and they fit fine. Im deciding on either the:

Dunlop GT Qualifier T's, Yokohoma Avid S/T's or the Firestone Firehawk Indy 500's

Im leaning more towards the Firehawks as they get great reviews. (Although the online survey things are all about the same)

 

depending on your wheel off set the fronts might rub in a turn, my front are 235/60's and they rub on a hard turn, as did my 225/60's

 

check your back spaceing.....if it's 4.75 and 7.00 wide on the rim...245/50 is your max as long as your ride hight and alignment are good. and for the backs your should be able to match that without a rim change.

 

235/60 is the best choice for a stock 15' wheel IMHO.

 

That being said, you can use your existing tire's specs and compare against new tires. Say you had P205/70r15's. You could do the math, then compare them against P225/60r15's. I'm not going to work it through for real, I'll leave that to you, but say the P225/60r15's are an inch wider than your P205'70r15's. Go to your car, "add" an extra 1/2 inch to each side (inside and outside) of your stock tire, and you can see if the P225/60r15 will fit.

Putting a taller rear tire on will increase your top speed, lower your 0-60 and 1/4 mile times, and make your speedometer read slower then what you're actually doing. (ex- doing "real" 55 mph, speedo might say 50 mph.)

Putting a shorter rear tire on will increase your 0-60 and 1/4 mile times, lower your top speed, and your speedo will read faster then what you're actually doing. (Ex- doing "real" 55mph, speedo might say 60mph.)