When you are changing rim sizes it is a good idea to know the Revolutions per Mile of your current tire. (if you are wishing an accurate speedometer)

I use http://www.1010tires.com/Tools/Tire-Size-Calculator before I go to the tire store.

The calculator does not go back to our cars but plug in 1990 Caprice just to get the calculator going.

Then put different sizes on the right.

I found that some tire stores seem to suggest sizes based on the stock they have.

Calculator example,

235/60R15 Will have 796.86 Revs per mile.

235/70R15 Will have 744.11 and

245/60R15 will have 782.70

Plug in your 14 inch size and try to find something close. The closer the number is to yours, the more accurate the speedometer.

A GPS will always be able to tell you if your speedometer is correct.

Hope this helps

 

 

 

 

 

when looking at rims what dose the "backspace" refer to?

 

14 or 15" Original wheels with hubcaps on skinny whitewall tires are good for a museum car that never sees much highway. I say skinny tires. I love whitewalls.

15x7" Corvette Rallys with good rubber are a vast improvement, and they bring a new attitude to any GM car 55- 90. A timeless classic look that will always be in style.

But nice 17x8 wheels shod with a tire of resonable OD (not super low profile rim protector), seem to fill a 60's B body wheel well just right. Purists be dammed, I think they just look better! (insert flame here).

Example,

Cheers, mc!

 

-- Edited by cdnpont on Saturday 28th of September 2013 10:11:54 PM