Stupid odd French tire size on old Mustangs

[XS650]

quote:

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Originally posted by Jonny Z:
Doesn't anyone think the tire sizing system is the most confusing one? I mean, mm and inch used in the same designator, where else do you see that?

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Not in the same designator, but Spark plugs mix inch and Metric in one small part.

 

[Jim 5]

I remember these TRX garbage on my '86 BMW 635csi.

I had the summer ones, plus a set of winters with (obviously) a dedicated winter tread.

I believe the size was 220 55VR 390 (I believe basically a 15.5" rim). They were really expensive, didn't perform well, but were the only ones that fit on the sweet looking BMW rims.

People were getting hurt from blown tires because they were forcing 15" tire on to the metric rims that were too big for a 15" tire.

I also remember those groovy curved 3 spoke aluminum TRX rims on the first year of the Fox bodied Mustang GT....was it '82 or '81?

Anyhow, ford also hosed its customers with this sweetheart deal with michelin.

I changed the power steering hose on my chev truck a month ago. The fitting on the pump side of the hose was imperial and on the box side it was metric. Gotta own metric and imperial tools to work on these babies. My buddy just rebuilt an LS1. Every single nut and bolt on that was metric. I'm not sure why gm would make the changeover.

 

[CapriRacer]

"I'm not sure why gm would make the changeover."

GM made a deliberate decision to use the metric system FOR PRACTICALLY EVERTHING quite a few years ago. That means that not only are the nuts and bolts metric, but all their specs are metric as well. This simplifies all the parts specifications so anyone can produce the parts anywhere. Also avaoids the exact problem you mentioned with adaptors, etc.

Probably the only thing they didn't change over was the size of their paper - A4 is kind of hard to get in the US.