Rev Limit

[Tom W]

What’s the factory rev limit for the 6cyl engines? My tacho (1970 S2, originally US spec) red lines at 5000rpm. I’d always assumed all 4.2s went to 5000, and it was the 3.8s that went to 5500. Browsing through some cars for sale, I’ve seen some earlier cars than mine (still 4.2) have a 5500 rev limit. Was the limit reduced at some point, or is it the difference due to SU vs Stromberg carbs?

[malcolm]

As far as I know, all 3.8s were 5500, and 4.2s 5000. That was the start of the red line mind you, and the 4.2 reaches max BHP at 5400 rpm. Not an SU vs Stromberg issue as far as I know, although that may effect the ability of the car to reach those levels.

Also, to hit the 150mph, those special cars had to reach the end of the red line in top! Wouldn't recommend it though