[Shawn D.]

Originally Posted by Daox

According to this: http://www.spdexhaust.com/pdfs/02-11...Collectors.pdf

The best angle is a 12-15 degree convergent angle with a 3 degree divergent angle. Interesting that those are different.

That style of collector is for use with an open exhaust, i.e. no exhaust system past the collector/transition. You will see these collectors on drag cars frequently, but I've never seen a street car with these AND an exhaust system.