Dave Anders has written a number of article on his R-4 speed and efficiency mods in Kitplanes Magazine - you can search for his name on the web site and find them.
Paul F. Dye
Editor at Large - KITPLANES Magazine
RV-8 - N188PD
RV-6 (By Marriage) - N164MS - "Mikey"
RV-3B - N13PL - "Tsamsiyu"
A&P, EAA Tech Counselor/Flight Advisor
Dayton Valley Airpark (A34)