Tire Size and Clearance

[1962birdlover]

I am buying new tires for my 1962 hardtop. I have called around a few tbird suppliers and have been told that it is normal with the 215 75R14 to have to deflate the rear tires to get them off and past the fender. Can anyone confirm this? I have read many posts here in regards to wheels and tires but am unsure.

I was also told that it is normal for the wheel stud centred style compared to the hub centred style of wheel. The weight of the car seems to be riding on the studs instead of the hub. Is this normal and safe or is a spacer required which I have read some members have? Thank you.

[Karl]

G'day.
I run 215 75R15. I haven't got original rims so I obtained a set of straight 15" rims. 215 is the width of the tyre in millimeters, 75 is 75% of the tread width for the height and 15 is 15" rim. so your tyre is slightly different to mine but could have the same problem.

If I jack up the rear using a jack under the axle, the tyre would stay in the wheel well and I would have to deflate the tyre to remove it. If I jack up the rear using the bumper jack as per the manual then because the axle hangs down then there is no need to deflate the tyre. Same would be if I jacked up the car under the body where the front of the rear springs joins the body, the axle would hang down and the tyre would be free of the wheel well.

14" rims have a smaller hole in the center then 15" rims. A14" rim on a 14" hub, the weight of the car is carried from the hub onto the rim. This also centers the wheel on the hub. If you take the wheel of and have it balanced they would balance the wheel using the center of the rim as a reference point.
For me, when I placed 15" rims on my 14" hubs the rim dosen't center on the hub by the center hole in the rim. As I do the wheel nuts up they could push the wheel to wherever they want to. So if I have the wheel balanced and it runs true on the balancing machine (it has used the center hole as a reference point) then when I place it on my car the wheel nuts could push it out and the wheel could run out of balance. Optimum word here is Could
Also the weight of the car now is carried by the wheel studs. Now this may be a problem and may not be a problem. I dove my car for some 10,000 miles with 15" rims on 14" hubs and it didn't seem to have a problem however there was vibrations in the car. When I did make up some spacers this did reduce some vibrations and the car ran better.

The spacer that I made up is quite simple and as you can see the difference with and without the spacer the wheel can no longer move out of balance.
Karl.

[1962birdlover]

Hello Karl,

That was a very excellent and detailed reply to my question. Very helpful. How did you make up the spacer? Did you fabricate it (machine it) or purchase it? Thank you very much.

[Joe Johnston]

Any small machine shop or someone with a lathe can make them. Just need the dimensions. Also are available from multiple sources online including Summit racing and many others. Google hub centric wheel spacers and you should find available stock sizes and sources for custom dimensions as well.

[1962birdlover]

Thank you.