Tires for 14x4.5 wheels?

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74RR

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I have a set of 14x4.5 wheels. What would be a good size tire to mount on these wheels?

They're for the fronts on my 74 Scamp. I'd like to go as tall and skinny as possible without bulging on the side wall of the tire.

Thank you.
 
185-14 is good. 175-14 will work, but may not have enough strength to carry the weight of the car in spirited driving.
 
Think I had 205/70-14 on the 5.5 wheels on Jamie's car. The rears had 225/70-14 but ther were really too big for the wheels
 
Stock sizes would have included D78. See what cross references to P metric. My recollection is 195/75r14.
 
Stock sizes would have included D78. See what cross references to P metric. My recollection is 195/75r14.

In terms of load carrying ability, this sounds right.

The D78 is the follow-on to a 6.95. By cross-section width, the closest tire would be a 175/75-14 in a radial. Usually a tire without a sidewall ratio, in actuality runs about 82. Since the sidewall ratio relates section width to sidewall height, it means that as the ratio increases, the taller the tire will be at a given section width. It also means that tire size increases (by section width), the tire gets taller.

Here is an illustration of how it can work out. Goodyear makes 175 thru 195/70-14 tires. The narrowest rim the 175 can be run on is 4½" wide. On a 5" wide rim, it presents a rolling diameter of 23.7". The same tire at 185/70-14 also has a 4½" rim width minimum, and a rolling diameter of 24.3". It is 0.4" wider at the widest part of the carcass than the 175/70 tire is. According to Goodyear, the 195/70-14 tire is not recommended for a 4½" wide rim. Hope this helps.

You may think that choices are limited. Be glad you're not looking for a 13" tire.
 
Yes, that helps a ton along with all the reply's. Thanks everyone!
 
The alpha-numeric system was based on load ratings. Although you have a goal of not visually bulging, a radial tire will always look a little flatter on the bottom than bias ply construction. It is important the tire is rated to support the weight its supposed to.

Checking my 1975 Plymouth Valiant owners manual, both 6.95-14 and D78-14 are recommended sizes with the 4 1/2 J rims. 5 1/2 JJ rims can use those as well as E70-14, E78-14, ER78-14. So as 2 Darts explained well, probably don't want to use those sizes or their equivalents.

Here's a chart at Tirerack that shows equivalent tires. D78 doesn't have a direct equivalent.
https://www.tirerack.com/tires/tiretech/45_conversionchart.html

It looks to me like P185/75R14 is the closest in terms of load rating without going wider than the rim would want. You can check each specific tire for recommended rim widths. I suspect they'll generally be as 2 Darts has said.
 
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