its a turbonetics stage III turbine wheel, which is 65mm/56.6mm inducer/exducer. a gt3076 turbine is even smaller than that, more like factory size

 

Umm yeah. This is awesome!

 

Everything is better when it's radioactive. Though truthfully, I have never been able to get a measurement off of thoriated tungsten. It's primarily an alpha emitter (with some beta and gamma from daughter products) but I don't have anything that will measure alpha directly.

The 3076R should behave much like a hybrid stock turbo except I went with even a smaller turbine housing.

We shall see what the result is. There just isn't much real world info on running small turbos on 13Bs. One can look at all the compressor/turbine maps in the world but that doesn't take into account a lot of real world factors (manifold, wastegate, downpipe, temperature, etc).

 

You should build a manifold with external wastegate and explain wastegate placement.

 

I had heard that some arc welding rods were radioactive. Perhaps the same or similar material?

 

On this setup I didn't want to go to an external wasetegate primarily for packaging concerns. I was worried I wouldn't have enough space. Seems that I could have used one though, even if the runner placement wouldn't have been ideal.

External wastegate runners aren't much more difficult than the main runners. Positioning is important so they should merge with the main runners at the area of highest pressure (typically just before the turbine). Otherwise they should merge at a shallow angle, or at an outside bend. They should be equal if possible however packaging makes this difficult. Packaging is often the issue with most manifold fabrication. It's quite difficult to equalize everything. I have equal length main and manifold runners on my RX-7 manifold and it's a bloody spaghetti factory. So the Cosmo runners aren't really equal but I doubt with such a small turbine side it will matter.

I don't know of any arc welding rods/electrodes that are radioactive but it stands to reason any of them which contain doping agents or have a flux that contains elements which have naturally occurring radioactive isotopes could be radioactive. Thorium, uranium, radium, potassium and strontium are common ones and may either be in use purposely or simply as a contaminate. However I doubt you'd ever be able to separate that measurement from background radiation unless you went to great lengths. People are likely a lot more radioactive.

 

how big is the internal wastegate?

 

Interesting. I've been using 1.5% lathanated, even though I asked the shop for 2%... Don't get me started on the counter guys at the LWS, I didn't have the best experience when I went to get a dual outlet regulator for backpurging.

One thing worth mention is that PVC pipe is the same dimensions as SS pipe, and a hell of a lot easier and faster to mock up, not to mention it's dirt cheap. I like to use the 45* bends too, as they'll hold the straights and SS 90*'s rather snug.

 

Looks like just a little smaller than 35MM. I don't know the exact size as I've not mentioned.

E3s are basically lanthanated with a few other additions so I suspect they behave very similar. Strangely my EconoTIG came with a single ceriated tungsten but the machine seems to hate ceriated.