On Oct 12, 10:21 pm, The Amaurotean Capitalist
wrote:
On Wed, 3 Oct 2007 15:34:25 -0600, "Daryl Hunt"

wrote:
Keeping it in the whatif department. What if they had installed decent
Turbos and Supers on the Allisons.

The turbo required a large amount of plumbing that was accomodated in
the tail booms of the P-38 and the enormous fuselage of the P-47.
There wasn't room for it in the P-39 or P-40.

Improving the supercharger efficiency of the Allison would have been
the feasable alternative, as the better supercharger largely explained
the contemporary single-stage Merlin's advantage over the Allison.
It totally explained it. The basic Allison block was superior and
smaller.

The solution Allison came up with was turbo compounding; far superior
to
either supercharging on its own or turbo-supercharging.