Large Image 1931 QCF-2 Waco, NX11241 sn 3453
According to Joseph Jupter's book,U.S. Civil Aircraft Series vol 5, there were 31 QCF-2 built. They were powered by the 1928 170 hp Continental A-70, (ATC 32), 544 in3. Which evolved into the R-670, (ATC 80). This aircraft, which was the first QCF, was used to test the first R-670 which had forward-facing exhausts. The first flight of the R-670 was in this aircraft on Dec 14, 1931. The R-670-B and R-670-F, (ATC 80), had forward-facing exhausts, while the R-670-D and R-670-H, (ATC 120), had aft-facing exhausts.
At some point in the mid 30s, the R-670 was redesignated as the W670, (ATC 162) This was when the roller bearings on the crankshaft mains were replaced with the troublesome ball bearings.
More about the Continental Radials at enginehistory.org
Reno 2019
