This post was spurred by a current posting in the Midget Classifieds for a USAC D2 car. As we have commented on repeatedly, cost of engines is a major contributor to declining car counts. That said, the rise of spec engine and/or limited modification series is a welcome development.
This link, for those who have not already seen it, is recommended. It is a good overview by people who do know (with the exception of a couple of engine power figures!!).
https://www.google.com/url?sa=t&sour...sqxPqR-2DG9uqH