welding up engine bay

Welding with a Mig without gas is like cutting steak with a spoon compared to a gas mig. I highly recommend a Miller Matic welder, they are the most consistant and most reliable on the planet. You should look into the 175 or 185 model. The 175 is good up to 3/16" plate but the 185 is good up through 1/4" especially when you know what your doing it can even tackle 1/2". The 185 series is the biggest 110 volt welder you can buy, and works flawlessly. If you bay looks decent without gas, wait until you finally have it you will be amazed. Just make sure your welds penetrate the metal, If not they will chip and flake off like a bad paint job. This is the most common mistake by a novice welder, even more so when using non gas, is the lack of heat and a good penetrating weld that will hold.