Didn't meant it that way :oops:
Normally I can find which things to edit if I want some things changed, but this time I just couldn't find it (happens quite often - if you need something, it's always gone)
When editing Tiberian Sun (English, no Firestorm), RULES.INI>General>Subterrainean vehicle, there's something called TunnelSpeed, right? What does it do? When I change the value nothing happens in the game...