Some months after buying my '89NA in 1996, took the car for a highway trip from central Alberta to Tulsa OK. Lost the A/C somewhere in Kansas, and it was really hot down there. This also qualifies for "fastest highway speed" though I don't trust the speedometer that far, the tach did get to 6,500 in 5th. (Stock tires, W58, 4.300:1 differential. You can do the math.) This was while there were "no speed limits" in Montana, on the I-15. (Yeah, I know, "Prudent and reasonable" -- I was being prudent, I didn't overrev my engine.
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Trip was 3 days there, 4 days back (Took a longer route for return, and didn't push much over 75mph for most of it.)