I've actually had mine right up against the limiter; it is a few miles an hour faster in 4th (auto) than 5th, like 133 in 4th versus 127 in 5th. (MPH)

Looking at the raw code I had a chance to see, I'll bet the limits are different for 2.5 and 3, and slushbox/stick.

 

Hi: My friend Patterson is referring to me I believe in recent post. I had my 02 2.5 5spd to 115 mph in 5th at an altitude of around 5500' above sea level in late winter outside Albuquerque NM. I would have to look at the pictures I took of my instruments (with on hand on the wheel and the other hand on my camera) to provide the tach rpms but I was no where near orange much less red line. At such high altitude, there would be a marked difference in available air I would think compared with standard temp and pressure. Yet I had no trouble getting the thing to go like this. There is something captivating, enervating, energizing and exciting about going this fast even if only for a moment. On the same road a couple years before, I had my 83 XJ-S 5.3 V12 at about the same velocity. I can tell you it felt VERY different!

 

I hadn't given much thought to elevation or ambient temp. I've been up to 110 mph using cruise control in my X quite a few times across the desert. I’ve held that for 30 minutes or so, then I hit the clutch and throw it in neutral, killing the cruise ctrl, and let it coast until 70 mph, then slip into 5th gear.

I think the rpms are around 5500 at 110 mph, I’ll have to confirm and then push past that, Ha ha.


Hey Tom, how was your XJ experience at high speed different than the X?