A 6th gear would be nice in my 59 1.5 at times. But I think it would run out of puff at times.Last week I was driving a Toyota diesel with a 6th gear box. As a hired car is was great as it indicated when I need to change up or down. This would be a little annoying if it was on my car as I don't need it telling me how to drive
My 59 reg. 1.4 seems geared as a van or pick-up rather than a car. ("Here he goes again ...") It revs about 15% higher than my old Skoda Favorits did. I heard that Nissan changed the final drive ratio after the early models, but I have no figures.