What I was talking about doesn't have anything to do with a torque converter. It happens in any type of gearing.
Think about it this way, if you have a small wrench on a bolt and your trying to move it at 100 ft/lbs torque, it will be hard to do. If you go with a bigger wrench, it will be easier to tighten the bolt to the same torque. Same thing with gearing. If you change the gears, it will take a lot less energy to move the car depending on the gearing.
Torque is force x distance.
Lets say you have 210 ft/lbs of torque and use a 3:1 gear ratio, it will multiply the torque by 3, giving you 630 ft/lbs of torque.
Not to offer any more insight, but in this example you did increase size of the output of torque,(longer handle) similar to bigger motor, which would produce more torque.