Dumb Question - Spare Tire Size 1964 C2

[Ed McGettigan]

Sorry to ask such a dumb question but here it goes - What tire size should fit in a 1964 Corvette spare tire carrier? Apparently, not a 205/75/R15 since I can't get it to fit!!

Thanks,

Ed

[Duke W.]

Re: Dumb Question - Spare Tire Size 1964 C2

Is the OD too big, or is it too wide? What year/type wheel is it mounted on?

Duke

[Jimmy G.]

Re: Dumb Question - Spare Tire Size 1964 C2

Even a 6:70 x 15 repo tire may not fit. Have had some luck with 195 x 15 radials but they are hard to find today. A real spare would always be nice, and work.

[Ed Jennings]

Re: Dumb Question - Spare Tire Size 1964 C2

There have been some previous posts on this matter recommending a 165/75-15. Believe these were originally intended for VW Beetles and may not be readily available any longer.

[Ed McGettigan]

Re: Dumb Question - Spare Tire Size 1964 C2

Thanks guys. I went back to the tire shop and they were kind enough to exchange the 205/57/R15 for the smallest size they had in stock which was a 185/65/R15 which just fits in the carrier. The carrier closes fine.

[Duke W.]

Re: Dumb Question - Spare Tire Size 1964 C2

I don't think you selected a very good strategy. A 185/65R-15 is speced at about 850 revs per miles versus 760 for a 6.70-15. If you install a 185/65R-15 on a rear with a positration axle and a 6.70-15 or near equivalent revs per mile radial, the car will exhibit severe torque pull and you could damage the positraction clutches.

A 205/75R-15 at 766 revs per mile is about halfway between a 6.70-15 and the 7.75-15 (775 revs per mile) and should make a suitable spare, but the combination of OD and width may make some 205/75s tough to fit in the spare carrier.

If this is the case my recommendation would be to shave a new 205/75 or buy a used worn example. As long as it holds air and has at least 2/32s" tread, it is suitable as a spare.

Also consider that if a midyear was ordered with optional KO wheels, the carrier cover front hanger bolts were longer because the 0.5" wider KO spread the OE tires about 0.2" wider, so you should look into the availability of longer hanger bolts.

Duke

[Joe Pennington]

Re: Dumb Question - Spare Tire Size 1964 C2

I agree with Duke about your tire choice. On my '64 I run 205/70R15's with 6" wide wheels(knock offs) on the ground but have a 195/75R15 on an original 5.5" steel wheel as a spare. The loaded wheel radius of the two tires are very close. I installed the longer, by 1", 10 1/4" long front tire carrier lid bolts in the front, avaliable at corvette central, etc, and installed 1/2" nylon spacers between the bracket and the frame crossmember at the rear. A lot cheaper then buying the longer lock bolt and bracket assembly.

[Joe Pennington]

Re: Dumb Question - Spare Tire Size 1964 C2

Forgot to mention. You can use the 185/65R15 as a spare with no problem as long as you always put it on the front, which means if you have a rear flat, pur the spare on the front and then put the front that you just removed on the rear. You should be able to get the flat 205/75R15 into the carrier, If not allway carry a old sheet so you can put it in the front seat, or your passengers lap. If you don't have positraction (most 64's had it) then ignore my posts, as you can't damage what you don't have.

[Jack W.]

Re: Dumb Question - Spare Tire Size 1964 C2

On the point made regarding longer front hanger bolts, I see mention in the aftermarket of three lengths - the "standard" length, a length for redline/goldline tires, and the length for KOs. As between the goldline length and the KO length, I assume the KO length is the longest - correct?

[Joe Pennington]

Re: Dumb Question - Spare Tire Size 1964 C2

The standard length is 9 1/4", with the K/O's it's 9 5/8" and with the gold/red lines it's 10 1/4". The K/O is only a 1/2" wider rim then the steel wheel(5.5") and only spreads the section width of the tire(6.70-15) out by approx 3/8". The gold/red lines are 7.75" section width vs the earlier 6.70" section width.