I'm looking for new tires and here comes this question again I'm sure.
The PO had aftermarket rims on the car and they work fine. They're 14's and the current tires on there are 215/60 R14
My question is, will 215/70's rub at all if I go up?
Seems that there aren't as many options in the 60 category.

The original tires for 14 inch wheels were 70 series. If you change to 15 inch wheels, the stock tires were 60 series.

edit: 14" tires are very hard to find unless they are for a trailer....do not use those.

[This message has been edited by Gall757 (edited 11-06-2018).]

Thanks! Also, glad to see you're from Michigan as well. I'm in the Hazel Park/Ferndale area.
In that case, I'll go for all four new to match em up since I have a hookup at Discount Tire.

quote Originally posted by Gall757: The original tires for 14 inch wheels were 70 series. If you change to 15 inch wheels, the stock tires were 60 series. edit: 14" tires are very hard to find unless they are for a trailer....do not use those.

Not quite right.
Depends on year, Depends on Model.
For example, 84 Coupe was a 13 wheel. 84 SE came stock with 215 60 14.
Other years used different sizes.

https://www.discounttiredir...tires/size/215-60-14

Several options available in 215 60 14. For the best ride, stick to the stock size unless you are doing other mods at the same size to compliment the change in tire size.

BF Goodrich still makes some 14 inch tires. I think Cooper might too. I'm getting 225/60-14s. Same circumference as the original 70's (within a few mm's), but a little wider. But yes, 14's are getting harder to find.

quote Originally posted by edfiero: Not quite right. Depends on year, Depends on Model. For example, 84 Coupe was a 13 wheel. 84 SE came stock with 215 60 14. Other years used different sizes. So to tack that on to my question, The 215 60 R14's on the car (84 base) run fine. The rims are 14. Im finding one option only in that size. Would 70's make it rub? I'd assume not if 60 R15's will fit on it as I've read. There aren't any suspension mods so its stock ride height. https://www.discounttiredir...tires/size/215-60-14 Several options available in 215 60 14. For the best ride, stick to the stock size unless you are doing other mods at the same size to compliment the change in tire size.

quote Originally posted by ShaneOC91: mostly I just want to know if (for ease of not needing to buy new rims) will 215/70's fit okay. Will the inch more or so make it too tall and rub the wheel well?

By my calculation, the tires you are asking about will be about .4" wider than the original 215/60/14s that came on those cars, and about 2.2" taller. Not sure if that is going to rub anywhere or not?

quote Originally posted by andreww: By my calculation, the tires you are asking about will be about .4" wider than the original 215/60/14s that came on those cars, and about 2.2" taller. Not sure if that is going to rub anywhere or not?

The width isn't any different and the current tires don't rub. Just the height of the tire.

FWIW, on my '84 SE I used 235/60R14 once without any interference; then for the last few sets I've used 225/60R14
BF Goodrich Radial T/A seems to be about the only one available.


Here's a site to peruse sizes etc...
https://tiresize.com/tires/Pontiac/Fiero/1984/SE/

[This message has been edited by David Hambleton (edited 11-06-2018).]

The selection for 215/60R14 tires now is basically BF Goodrich Radial T/A's (crap) or Chinese garbage brand tires (bigger crap). This is why I'm upgrading my 84 wheels to Fiero GT 15's, there actually IS some selection.

if you have AfterMarket wheels then you need to get more data because AM wheels can be anything... like wider and/or different offset/backset.
215 tires often run wider rims then OE but can't trust PO.
Look at back of wheel for size width model etc.

Tire specs at marker's web site covers test rim and range of rims to mount them safely.
The Test rim is where the profile numbers are accurate. IE the Section Width (s) in sss/aaRdiam
Example: https://www.goodyear.com/en...etailsViewSizesSpecs
Goodyear Assurance® All-Season
Tire Size 205/60R15
Approved Rim Width (in.) 5.5 - 7.5
Measured (Test) Rim Width (in.) 6.5 (when 205 is accurate.)

205 is Not the Tread Width. Very easy to find 195 tires w/ same TW as 205 tires. (but GY doesn't have TW on most or all tires on the site.)
See my Cave, Tires and Gear Ratio more so when using bigger tires...

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

215/60-14.........215 mm section width divided by 25.4 = 8.46 inches, times 1.2 (EACH sidewall = 60% of section width) = 10.15 inches + 14 inches (rim diameter) = 24.15 inch total diameter.

215/70-14.........215 mm to 8.46 inches, times 1.4 (2 x 70%) =11.84 inches plus 14 = 25.84 total diameter......

So plus approx' 1.7 inches diameter or .85 inch radius. It might actually be better to run a 205/70-14 which is a little tighter on the rim (Width-wise) which will help stabilize the tread better and the diameter would be approx' 25.3 inches....that would be only 1.15 inches difference in diameter.

I am running 205/55-16 on the front (Total diameter = 24.8 inches) and 225/55-16 on the rear ( 25.74 inches) and my car is lowered approx 1 inch....the fronts barely rub but I cut 3/4 inch off the bump stops up front.

quote Originally posted by cvxjet: 215/60-14.........215 mm section width divided by 25.4 = 8.46 inches, times 1.2 (EACH sidewall = 60% of section width) = 10.15 inches + 14 inches (rim diameter) = 24.15 inch total diameter. 215/70-14.........215 mm to 8.46 inches, times 1.4 (2 x 70%) =11.84 inches plus 14 = 25.84 total diameter...... So plus approx' 1.7 inches diameter or .85 inch radius. It might actually be better to run a 205/70-14 which is a little tighter on the rim (Width-wise) which will help stabilize the tread better and the diameter would be approx' 25.3 inches....that would be only 1.15 inches difference in diameter. I am running 205/55-16 on the front (Total diameter = 24.8 inches) and 225/55-16 on the rear ( 25.74 inches) and my car is lowered approx 1 inch....the fronts barely rub but I cut 3/4 inch off the bump stops up front.

This was the math I was looking for. Thank you. Just wanted to know if the extra sidewall height would rub. I KNOW the current rims/tire combo work because they haven't rubbed when I've driven it in. Just needed to know if the size up was going to make the sidewall too tall. But sounds like if you're lowered an inch and you barely rub, then it shouldn't rub since its stock.