Tire size for a 123GT

[vmg]

Hi guys:

Can anybody tell me the equivalent to the original tire size for a 123GT? Truth is I want it for a 122S, but since I cannot locate the correct 165/80R15 in Mexico, where I live, I am thinking of using some other alternative that would also be original to a similar car.

So, was it the same on the 123GT or did ti have a different tire size?

Thanks!
Victor

[old fart]

Tyres were the same size.

[Army]

Victor,

I don't know what's available in Mexico for you to buy.

If I were you I'd look at one of the many on-line tyre calculators such as this one =>

https://www.rimsntires.com/specspro.jsp

Plug in the numbers on the left for the stock situation and then modify the right hand side of the calculator with the tyre combinations you can buy - you can see on the graphic if the new combination is getting wider or whether the speedometer reading is going to be miles out or not.

Once you've got what you think will be a suitable (or bearable) solution have a chat with a decent tyre fitter to make sure they think the tyre will stay on the wheel (!)

[Derek UK]

Originally Posted by old fart

Tyres were the same size.

The GT also used the same 4" rims as the standard saloons. Only the Estates used a 4 1/2" rim. It's a small but useful increase in width if you can find a set of those. Also used on the 1800's, and these were a slightly lighter wheel than the Estate ones. Again a useful saving. Although the tyre makers won't recommend it, the 185/65/15 can be used, but better with the 4 1/2" rims. Rally style driving will have them rolling around on the rims quite a bit. These are a bit smaller in diameter than the 165/80/15 so will give a bit of speedo error, but can make the car feel a bit perkier. This size easy to find so a big plus.

[AndyV7o]

Im surprised you cant get that size in mexico, are there not loads of beetles still around there? Its std size for those too...
Direct swap would be 185/70 but 185 on a 4" rim is not very stable, its pretty narrow for a 165. A 185 -should- be mounted on a 5"- 6.5" rim.
Can you not order online? Many online retailers should have 165 r15.

[classicswede]

I have been using 195/65/15 on the original 4j wheels for the past 20 odd years. They are a very tight fit but that does need the tyre does not float on the wheel at all. Running @30PSI tyre pressure the tread wear is even. In theory the tyre is too wide and could result in the middle of the tyre wearing first in real world this does not happen.

185/65/15 (common on Saab) are an option or 175/70/15


165/15 (or 165/80/15) or what would originally have been fitted

[AndyV7o]

Originally Posted by classicswede

I have been using 195/65/15 on the original 4j wheels for the past 20 odd years. They are a very tight fit but that does need the tyre does not float on the wheel at all. Running @30PSI tyre pressure the tread wear is even. In theory the tyre is too wide and could result in the middle of the tyre wearing first in real world this does not happen.

185/65/15 (common on Saab) are an option or 175/70/15


165/15 (or 165/80/15) or what would originally have been fitted

It is putting undue strain and loading upon the bead area of the sidewall though, you run the risk of damaging the integrity of the tyre. Ofcourse you've not had any issue, so clearly driving style and keeping an eye on pressures are working reasonably well, but I would not condone others following suit.

[vmg]

Thank you guys!

Mexico is a very complex country in many ways. One of them is importing tires, so I prefer not to go through the hassle if I can... but will do it if I really need to.

Yes, loads of VW Bettles here, but the tire used for them is 155/80R15. No 165's unforutnately. I tried to find for an Alfa Giulietta Sprint restoration I am doing and ended up importing them.

Victor

[AndyV7o]

Of course another option is to get the wheels, or a second set, banded. An inch inside and outside, or 1.5 inch outside 0.5 inch inside, would give you 6' rims which will comfortably and safely take a 185 or 195 width tyre.

[Army]

I'd just go for the local 155s - they only have a slightly smaller diameter resulting in a 2.5% reduction in road speed compared to what the speedo says...