Currently my car is running P205/75 R14s. Will the tires rub if I go an inch taller? I wouldn't think so; it looks as though there's at least 2-3" of clearance. I want to fit a 15" rim while maintaining a good amount of rubber. Has anyone done this before? Thank you.

 

73 Dart 440 4 door sleeper car.
I have 225 65 R15 tires on 80's cop car diplomat wheels in 15X7 size.
they are fine in the rear.
The fronts hit the rear of the fender well.
My surprise, the offset is different on the 80's car.
It is a hot-rod car so I just clearanced the tires with a rotary cut-off tool.
With decent paint it is hard to tell BUT I would not slice-and-dice a car you want to be as original.

 

Hmm. I decided to go with 205/70/R14s in the front, and 215/60/R14s in the back (as recommended by my local tire shop). I got them the other day, and the front tires are taller than the rear tires. Does that make any sense? The larger the first number, the taller the tire should be. I know that the second number is a percentage of the height for the width. I'm thinking I'll have to buy 195/70/R14s or so.

 

A 205/70x15 is almost an identical match in diameter and width to the 205/75x14. You can check various combinations at tire calculator sites like http://www.miata.net/garage/tirecalc.html So if they fit now, this 15" size will also work and you haven't lost much in the way of sidewall height.

 

I put 15" Cragars on my 1971 Demon 340 without any problems.
FF

 

You can easily fit 15 x 7's with stock back spacing and 255/60's on your car

 

Yes it does.

Tire height formula:

Take the width in mm (1st number - 205 etc.) x the "aspect ratio" (50-60-70 etc.)
divided by 25.4 (converts to inches) x 2 (sidewalls) + the rim diameter in inches =
the overall height in inches when mounted on the median recommended rim width
and inflated to the recommended pressure.

The smaller the aspect ratio (ie. 60 instead of 70) the shorter the tire for a given
tread width. In your example the height of the front sidewall is 143.5 mm (205 x 70)
and the rear sidewall is only 129.0 mm (215 x 60) - shorter.

A really tall tire for a given tread width would have an aspect ratio of 75 or 80 while a
really short tire would be more in the 60 or 50 range.

Your front tires should be around 25.3" in diameter and the rears should be around 24.2"
in diameter. You probably should have bought 215/70-14's for the rear instead of 60's.
The 215/70-14's are 25.9" in diameter.

A 245/60-14 would be the same height - 25.6" in diameter - but would be 40 mm wider
in section width (40 divided by 25.4 to convert to inches = approx 1.6 "). The section
width (1st number in size) is the widest part of the mounted and inflated tire - might
be the tread or might be the sidewall, depending on the tire design.

Using this formula, adding an inch of rim diameter (15") and using a 225/60-15 tire gives
you an overall diameter of 25.6".

Whoever advised you at your tire dealer is wrong and misadvised you on proper sizing.

 

Could you fit a 16x9 rim on the rear with like 285/50 tires without having to do any body modifications or tubbing the rear wheel wells? I'm trying get a bit of a lift in the back without having to do a suspension lift. I got a 74 Dart Sport.

 

Moparts.com is a website primarily dedicated to older iron.
They are more adapt to have a member with first hand knowledge or
wheels on a 72.
As previously indicated we run 215-65R15 on 7 inch rims, cop car wheels off an 80's Diplomat on our 73 440 powered Dart.
We run 3.0 RIR with a TF727. Top speed is somewhere I have never been!
They are plain Jane but are apropos for our sleeper style.