1980 C3 spare wheel size

[NMcC3]

Hi, my 1980 has 255/60/15 tyres on standard original Alloy wheels. The spare wheel is incredibly perished and almost impossible to read the tyre size on it. I want to clean up the steel spare wheel and replace the tyre. I think it’s a 195/80/15. Looking for a suitable tyre on line and they are all terrain type tyres with that measurement. On an American Corvette forum they talk about spare tyres being 225/17/15. Whey wouldn’t the overall diameter be the same as the standard wheel? The spare tyre measurements suggest either a 10 mm or 20mm diameter increase?
Any help would be great. Thanks
Nick

 

[Roscobbc]

Hi, my 1980 has 255/60/15 tyres on standard original Alloy wheels. The spare wheel is incredibly perished and almost impossible to read the tyre size on it. I want to clean up the steel spare wheel and replace the tyre. I think it’s a 195/80/15. Looking for a suitable tyre on line and they are all terrain type tyres with that measurement. On an American Corvette forum they talk about spare tyres being 225/17/15. Whey wouldn’t the overall diameter be the same as the standard wheel? The spare tyre measurements suggest either a 10 mm or 20mm diameter increase?
Any help would be great. Thanks
Nick

Adrian Dromey (on Ebay) is (or was) selling a late C3 seemingly unused but original spacesaver wheel and tyre.

CHEVROLET CORVETTE C3 GENUINE 15" SPACESAVER. | eBay

Find many great new & used options and get the best deals for CHEVROLET CORVETTE C3 GENUINE 15" SPACESAVER. at the best online prices at eBay! Free delivery for many products!

www.ebay.co.uk

 

[NMcC3]

Thanks very much

 

[Oneball]

The later cars (77 on I think) had a different fuel tank which required a space saver type spare rather than the full size one for earlier cars. The space saver wheel is a 15” x 5” with a 195 80 15 tyre.


As it’s only for temp use and says as such on the space savers I’d have thought a new road orientated SUV tyre was preferable to something 50 years old

 

[Roscobbc]

The later cars (77 on I think) had a different fuel tank which required a space saver type spare rather than the full size one for earlier cars. The space saver wheel is a 15” x 5” with a 195 80 15 tyre.


As it’s only for temp use and says as such on the space savers I’d have thought a new road orientated SUV tyre was preferable to something 50 years old

An interesting conundrum - an unused inflated tyre that has remained (presumably) in a spare wheel carrier and not exposed to potential ultra violet and atmospheric damage - vs - potential degradation of rubber/canvas/wire structure...........wonder what a knowledgable, technical experts answer would be?