The speed is in the .sim files. ../data/submarine/NSS_Uboat*.*
Use SH3 MiniTweaker to change them
In order to do this for travelling only, I would also change the "gears".
I would keep speeds 1,2,4 and 5 for playing and 3 only for travelling:
There is a code somewhere (anyone can help?) that can adjust the "gears" i.e the percentage of the max speed. So if you set max speed 35 kms (double of an average sub) then your tweaked gear configuration would be something like that:
Speeds: 1=15%, 2=25%,
3=100%, 4=40%, 5=50%.
This way you'll get what you want (cruising with 3) and be within the limits of a challenging experience. Don't know what will happen with your fuel consumption...
I guess you'll have to tweak this too to compensate. It's also in the .sim files. Look for surface range.
