Resistance Seam Welding is a resistance welding process that produces a weld at the faying surfaces of overlapped parts along a length of a joint. The weld may be made by overlapping weld nuggets, a continuous weld nugget or by forging the joint as it is heated to the welding temperature by resistance to the flow of welding current.
Tig Tungsten-Inert-Gas used for welding metals such as aluminium and magnesium
Mig: Gas Metal-Arc Welding (GMAW). A welding process in which fusion is produced by heating with an electric arc between a metal electrode and the work. Shielding is obtained from an inert gas such as helium or argon. Pressure and/or filler metal may or may not be used.
All these are different types ow welds which are used for different metals and differen purposes. But the main common purpose is to provide a lighter and strogner weld
As for rally cars they do use busing but of different materials like polyurethane and others which are stiffer and do stop the movement of the engine during acceleration and hence transfering that power to the wheels. But the car vibrates with the engine and is felt immensely in the cabin.