316 is what the general consensus is.  What I am looking for is stainless steel wire, I'd like to do my next setup with the same config in the pics I put up prior.  Sheet stainless wouldn't be bad either, would require a design change but doable.  Science is great isn't it?  Makes me feel like I'm in hs again.  I can probably work with any type of scrap and make something happen, but its hard to tell.  The main issue was when the h2o split, the oxy coroded the hell out of the galvanized I was using.  This happend in a matter of five minutes.  Looks like it had been out in the rain for about 2 years.  Interesting stuff nontheless. 

Its got to be 316 due to the harsh environment.  I could definately work with the sheet those sizes are def doable.  Wouldn't even need that much maybe two or three sheets of the 8 by 40.  Is that bendable?  I'm not to familiar with the gauges of sheet metal.  How much to ship to Twentynine Palms Ca?  I would pay for it.  Its gotta be cheaper than buying, sheet metal prices are throught the roof down here.

Its what forms the electrode.  When you pass electricity through it, it splits the water into a hydrogen/oxygen gas.  This causes an extreme enviroment, I can show you pics of what happens after about 5 mins.  Its instant corrosion, looks like its been sitting in the rain for years.  Stainless will stand up to it for an a period of time but will eventually break down.  Copper is useless it corrodes to easy, galvanized alum is a waste of time as I found out.  The stainless is the most cost effective material I can find to test with.  Thats the short answer.  But I can use it.  Its a neat project though.  We have alot of time on our hands up here in the desert.

In my reading and understanding of what goes on, two things might have caused this.  1.  Due to an excessive enrichment of the fuel/air mix, the timing was not retarded enough to allow for proper ignition.  For example, if you were set at 8 deg before top dead center, and the plug fired, the resultant explosion what be faster, actually trying to drive the piston down on the up stroke, thereby causing a bent or broken rod.  2. You possibly didnt run a leaner amount of fuel, which would do the same thing.  Thats sort of the point of this, if your running leaner, but getting the same results, viola, better fuel economy.  So let the experimentation continue!

Or #3). I washed the engine and standing water on the intake leaked thu a bad intake gasket and filled up 2 & 4, turned the key and produced pretzels!