P-63 (?) Airacobra/Kingcobra power question

In article ,
Ron Wanttaja wrote:

Ricky wrote:
A question for the physics-minded among us, or for anyone who just has
the answer.

I have heard the Airacobra was underpowered and that got me to
thinking;
Does having an engine at the middle of the fuselage (in any plane for
that matter, like the XP-58) and connected by a long shaft contribute
to a loss of power delivered to the propeller? In other words; would
there be more power delivered the closer the engine is to the prop?
Does the shaft "eat up" power in any way? I am a mechanic and pilot
and fairly knowlegable about a/c physics & aerodynamics but this has
me stumped.

[snip]

Whether it was enough to matter, in the case of the P-39, is another
thing. ISTR the P-39's problem was the lack of a turbocharger rather
than overall low power... the Airacobra started losing oommmmph above
12,000 feet, and it turned out that most of the combat was higher than that.

Combat in the ETO tended to be higher than other theaters, which, since
the USAAC pulled the turbocharger from the P-39, hamstrung it in that
arena. The Airacobra was also a small aircraft, with limited fuel, as it
was designed as a point defense fighter, and lack of range hurt it, too.

That said, the Russians liked it pretty well, since air combat on the
eastern front tended to remain below 15,000', and it performed well down
there against the Luftwaffe. (In spite of the 37mm cannon, the P-39 was
used much more in the anti-air role, and not against German armor; the
Il-2 was much better down in the mud.)

The P-39/P-400 didn't exactly shine, not that it embarrassed itself, in
the Pacific, partly due to the long distances that were common there.