Looking good... Awesome looking welds as usual! If you wouldn't of forgot them at home, i could of been looking at the actual headers instead of a picture!! Oh well you'll just have to make another set.
Here is a study on individual cylinders. Again this is just a computer flow study. (This is my interpration of the flow study)
Fist set is the elbow primarys. It appears to have less circulation (or dead flow) that he straight primarys, and higher exit velocity. I'm sure that the overlapping of...
Here are a few screen shots of the flow simulation I did of the header.
The first show the primary made out of a elbow into the collector, the second show straight pipes going into the collector.
The first model(which is how it was built) shows higher exhaust velocity at the exit of the...