Why are Radial Engines so Hard to Start.
Hmmm, I never thought they were so hard to start, and I've started plenty of 'em over the years.
R3350's both turbocompound, and otherwise.
A few R4360's (Boeing Stratocruiser)
Many R2800's (DC-6B's)
R1830's (DC-3's)
Of course, I didnt start them in -40C, either.