Due to the exhaust ports being located on the right side of the engine, the throttle body will be located far back in the engine compartment. This is inefficient seen from a temperature point of view, since the airfilter is an open type. The intake manifold, shown in the picture, is made of cast aluminium, and the "plan" is to move the throttle body to the other side of the manifold, such that the there will be a short direct path towards the front of the car (and thus fresh air).
The MIG was loaded with a bottle of Argon and roll of aluminum weld wire, pictures shown below.
Preliminary results shows reduced intake temperatures especially when idling. The increase in distance from the air filter to the cabin, has also reduced some of the unpleasant noise.
The problems are simple:
- Can it be done?
- What is needed to weld cast aluminium?
- Will such a welding be reliable, or can I expect to loose the throttle body some day(!)?
To ensure that the flow is the same as before it must be best to cut of both ends of the manifold plenum just outside the uniform mid shape. Switching the end parts shuld do the trick. If this is not possible it is no problem to make a new plenum from a thich walled pice of aluminium pipe and weld the old throttle body atatchment on the correct end.
Cast aluminium can be welded if it is of good quality, that is if it dosent resemble swish cheese in ist structure.
The correct tool for welding aluminium is a TIG welder able to provide AC current at about 200 - 350 amps.
An alternative is to use a CO2 welder with a special welding wire and gas. But it ursurly gives a poor result compared with TIG weldings.
Any way it is very importent that the welding area is 100% clean before a weld is atempted. Sand blasting is recomended.
If done correctly, a weld is any bit as strong as the base material. But often forgot is the design resulting i cracks from overloaded spots.