21 inch tires

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Philip
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21 inch tires

Post by Philip » Mon Nov 27, 2023 1:56 pm

i recently bought a set of 21 inch wire wheels. the tires are in good shape 440-450-21
the outer dia is 28 inches the ones i have now are 31 outer dia. i have 4 of them i guess
they will look ok any thoughts on why the difference. philip

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Henry K. Lee
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Re: 21 inch tires

Post by Henry K. Lee » Mon Nov 27, 2023 2:03 pm

Are they aired up? Are your old ones 4:50/4:75?

Hank


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Philip
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Re: 21 inch tires

Post by Philip » Mon Nov 27, 2023 2:19 pm

all aired up all marked 440-450 21

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DanTreace
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Re: 21 inch tires

Post by DanTreace » Mon Nov 27, 2023 3:11 pm

Tire brands are different O.D. need to check the mfg specs.

Quick review showed;
Coker 450x4.75 21 as 30.37" OD
Goodyear Silvertown 440x450 21 as 29.27" OD
Firestone 440x450 21 as 30.79" OD
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Norman Kling
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Re: 21 inch tires

Post by Norman Kling » Mon Nov 27, 2023 4:26 pm

They will fit on your car and only difference you will notice is those with the larger diameter will go a bit farther per revolution. Only will make a bit of difference if you have an odometer or speedometer.
Norm

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TRDxB2
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Re: 21 inch tires

Post by TRDxB2 » Mon Nov 27, 2023 6:32 pm

Philip wrote:
Mon Nov 27, 2023 1:56 pm
i recently bought a set of 21 inch wire wheels. the tires are in good shape 440-450-21
the outer dia is 28 inches the ones i have now are 31 outer dia. i have 4 of them i guess
they will look ok any thoughts on why the difference. philip
Not sure I understand "the outer dia is 28 inches the ones i have now are 31 outer dia." what is the 28 inches inferring to an old tire or un-aired new tires.
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Humblej
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Re: 21 inch tires

Post by Humblej » Mon Nov 27, 2023 7:06 pm

Not a problem, sounds like you have Firestone tires.


ModelTWoods
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Re: 21 inch tires

Post by ModelTWoods » Tue Nov 28, 2023 8:34 am

DanTreace wrote:
Mon Nov 27, 2023 3:11 pm
Tire brands are different O.D. need to check the mfg specs.

Quick review showed;
Coker 450x4.75 21 as 30.37" OD
Goodyear Silvertown 440x450 21 as 29.27" OD
Firestone 440x450 21 as 30.79" OD
Silvertown was a B.F. Goodrich brand. I think they are still made in a 21" size. Goodyear 21" are called All Weather Balloon tires. I have a set. They are still made. I think Firestone 21" tires are, also, still being made. The 1926 Fordex sales manual states the improved Ford is equipped with 30" diameter tires but does not specify the exact size. Most original factory sales photos show improved cars with Goodyear tread tires. Kelsey Tire Co. in Missouri is the major U.S. distributor for these brands of 21" tires. Snyder's and probably Lang's and Chaffin's buy tires wholesale from Kelsey.

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