How to best shift gears on a manual gearbox

[meridivs]

What is the best speed (in Km/h) for changing into the 2nd, 3rd and 4th gear on a 4 speed manual gearbox Mercedes W123 with a 3005cmc diesel engine (617.912)?

I'm asking because I find the speedometer markings totally unhelpful (I rarely drive past 70Km/h in the 3rd gear for example). Does anyone have any recommandations based on his experience about this issue?

 

[Dieselman]

use the rev band of max torque -500 Rpm and +1000Rpm. In other words keep the engine operating close to the maximum torque as torque equals accelleration.

 

[meridivs]

I don't have a turometer so I don't know the number of rpm's my engine has at a given time. Actual speed is the only indication I have right now. Can you tell me, instead, the speed I should shift up into the 2nd, 3rd and 4th gear?

 

[pint6x]

Presumably the markings on the speedo are the maximum speeds in which you can safely use each gear.

In practice most people would change up long before getting anywhere near this figure.

Trust your instinct - if it feels right and accelerates as you would expect, you're probably doing it right.

 

[reme2493]

its best to change into 2nd gear at around the red limit on the rev counter same again with 3rd and 4th gears. it all depends realy an the engin and gearbox in a car

 

[Shude]

I don't have a turometer so I don't know the number of rpm's my engine has at a given time. Actual speed is the only indication I have right now. Can you tell me, instead, the speed I should shift up into the 2nd, 3rd and 4th gear?

Erm?

its best to change into 2nd gear at around the red limit on the rev counter same again with 3rd and 4th gears. it all depends realy an the engin and gearbox in a car

There is no RPM gauge in his car.

It's also not true that the best place to shift for performance is in the red part of the RPM gauge, a lot of cars are out of the "power-band" and into the "noise-band" by that point!