VCCA Home Forums TECHNICAL - 1945 AND NEWER 1949-1954 Tire to fit in trunk tire well

I am looking for a radial tire that will fit in the trunk tire well in my 1954 BelAir. I have a P225x75x15 as a spare now but to put it in the trunk tire well I have to let most of the air out of it to fit which defeats the purpose of having a spare tire.

The stock 6.70x15 has a cross section of about 6.7". You'll need to shop for a tire that same size. The metric sizing like P225 is in millimeters. 225 mm is about 8.8". To get a 6.7" cross section you'll need a P170 tire. I don't know if anything like that is for sale in this country. Coker and Diamondback sell bias look radials but you'll need to visit their sites to check their specs.

Coker has a tire size equivalent chart here: https://www.cokertire.com/blog/tire-size-cross-reference
They say a P205/75-R15 is equivalent.

A 205 is roughly the equivalent in diameter but it has an 8" section width and likely won't fit the tire well. I'm running 205/75s on my 53. FWIW I have a bias 6.70x15 as a spare. While it's not advisable to mix bias and radial for long term use I've had no troublesome experiences using it in the past as a temporary spare.

The higher the ratio number the narrower the sidewall. Most tires are 75 or lower and too wide for tire wells. If you can find 195/85 or 205/85s they might have a better chance if fitting.

I agree with Tina’s approach for a spare tire.

We are using a 6.00-16 (the original tire size) for the spare on a ”˜49 1/2 ton pickup. We are using 195/70R-16’s for the running tires. Fitting that size into the spare tire carrier was a struggle due to the width.

The reality is that most of us never use a spare tire these days for any of our vehicles. Compared to when these older cars were made think of the better road conditions, much better tires construction, and the fact that we as enthusiasts pay attention to our tires. We just do not get into situations where we need a spare.

Well I bought a 6.70x 15 bias ply truck tire for a spare and it fits perfectly in the spare tire well. I bought a truck tire because looking for a 6.70x15 car tire I could only find tires priced at $200 or more. I found this tire on a website called Simple Tire and it was only $90 something with shipping and it is a new tire.