Tires, Speedometer Errors and other thoughts:
The funniest thing about all of this is that I researched potential tire choice, type, and size on this forum already. I felt confident that given the marginal discrepancy in speedometer reading, the ease of procurement, that a decent 195/75/R14 was the way to go. This information is what biased my choice in the first place.
Michael, you of the gorgeous red ’69 280 SL. Regarding speedometer accuracy, it used to be a factor in the road tests done by Road and Track magazine when your car was first built. It was part of their road test data sheet. I read Road and Track and Car and Driver like bibles when I was a kid, as I loved cars. As I remember, speedometer error tended to range from the optimistic, to the wildly optimistic. A ten per cent variance at an indicated 100-MPH was not uncommon. Meaning the car was actually travelling at 90-MPH when it indicated 100-MPH. These were factory original discrepancies, only altered by radar accuracy. I do not know the discrepancy of the 280 SL, but I'm sure you could research it. The Germans were pretty good at these things, but it was terribly rare that anyone got anything right. You might find such a search an interesting read. It might also allow to you blast further into your speedometer reading without fear of retribution.
I am not pissed at anyone for wanting to talk about tires. I do not want to stem the flow of information, and I am aware how information changes forms.
But Barn Find is for anyone who dreams of taking a shot at the improbable.
Tires are just round rubber donuts that get the job done.