P-38 Exhaust

Time to do my share to improve the S/N ratio here at r.a.m,
or at least make a try at it!

It's easy to overlook. No exhaust pipes visible protruding
from the sheet metal around the Allison engines on the P-38.

Given that Lookheed, and Kelly Johnson in particular, paid
a lot of detailed attention in the design and execution of
the aircraft, I'm wondering why they never made an effort
to use exhaust thrust to squeeze a few extra hp/mph out of
the engines for this aircraft.

The Spitfire in particular, but I believe the P-51 as well,
all made use of exhaust thrust to gain a bit more speed. Given
the P-38 was designed in 1937-ish and didn't appear in person
until about 1939, perhaps the advantage of using thrust to
boost speed a little wasn't really thought of? Perhaps the
Allison at the time of design just didn't have the oomph for it?

Also, exactly where does the P-38 engine exhaust exit the
engine? Seems to be a big, upward facing pipe in the vicinity
of the turbocharger, but never really knew if that was turbo
intake or an exhaust of some sort.

Upward directed exhaust doesn't seem a good choice.


SMH