in between them fighting words

in Aviation Historian 23 . My lack of a formal education gets me lost immediately . This coefficient of drag thing is multiplied with something obviously : When the value for a P-47 is the same with a PR 19 brand of Spitfire at a given speed and the Thunderbolt is twice the weight of the latter that means it needs twice the horsepower ? It gets even hazier and ı learn there is something with the design of the after end of the central structure of the P-38 that causes massive drag and Lockheed insists on keeping the design . Now that nobody has ever heard of r16 the chief designer let's try to solve the riddle ...

yeah , exactly ... What if ... One was to inject some airflow to the equation ? Now that ı also know nothing about turbosuperchargers , would it be possible to divert the "exhaust" from the booms to the central pod so that they would sort of provide an "extension" of the kind required ? P-61 of the same formula extends the rear gunner's station well aft , doesn't it ? Driving hot pipes through the wing , next to fuel tanks , really smart and every brilliant aircraft designer must fancy that ? Well , am not one . And apparently Russians fed exhaust gases right into fuel tanks of radial engined Lavochkin fighters as a safety measure in the same timeframe ? Assuming that worked , any lack of the same would immediately cause drag ? Now that ı have read it somewhere that RAF once wanted a divebrake on the Mosquito and no successful design was possible . Also read it somewhere that the P-38 had some intermediate flap setting for air combat . Even if it would be 10 years ahead of things , in case this exhaust was somehow fed to to those inner flaps between the fuselage pod and engines and the flaps out of engines supported the ailerons for increased roll authority at high speed ? If turbos do not work , you won't be at high speed anyhow ? Err , uhm , er , strategic dive bomber . Modellers will need those British rocket rails under the fuselage , though longer and sturdier . Easiest way to tell an Atlanta from a Lightning ...

Dear r16,
Wow!
You covered so many different topics in one paragraph!
May I suggest breaking each question into a single paragraph?

As for drag created by the Lockheed P-38 Lightning's short center cockpit pod …. That may have looked good in the wind-tunnel, but real life/aerodynamics are far more complex. Yes, a longer aft pod would have improved airflow to reduce drag. The simple answer is another sheet metal cone with shallower slope.
Your suggestion is waaaaay more complex ...more like the base-bleed artillery shells introduced circa 1970.

Yes, you do have to be careful not to route hot exhaust/supercharger pipes too close to fuel tanks.
Lavovchin - and some later jets - routed exhaust gases into fuel tanks to reduce the risk of accidental fires. The primary ingredient is non-flammable carbon monoxide. Pumping cooled carbon monoxide into fuel tanks reduces the amount of ullage. Ullage is the fuel fumes - mixed with air that fill the top part of a half-empty fuel tank. When the fuel-air mixture approaches 1:7, it becomes as flammable as carburetor output. Ullage is far more flammable than liquid fuel.

The primary motivation for testing dive brakes on Mosquitos was to prevent Mossie night-fighters from over-running their targets. They needed rapid closing speeds to catch targets, but reduced the number of seconds to fire. They hoped that deploying speed brakes would allow more gun-time. Unfortunately, they only tested radial speed brakes on a single Mossie and they proved too crude. Radial speed brakes vaguely resembled an umbrella deployed just behind the wing. I suspect that it created too much turbulent airflow over the tail. No body has used radial speed brakes since then.
Later jets perfected speed brakes on aft fuselages and now the standard is a single speed brake on top of the fuselage. Jets primary use speed brakes to allow them to carry some power into the landing flare. This because jet engines are slow to accelerate in the event of a missed landing approach. Slow acceleration becomes twice the problem when "bolting" (missing the arrestor wires) from aircraft carriers.

Some airplanes do link ailerons to flaps. This linkage is most popular on short take-off and landing airplanes like those designed by deHavilland of Canada. STOL DHC bushplanes like Beaver, Otter, Cariboo, Buffalo and Twin Otter "droop" ailerons when flaps are fully extended. Ailerons don't droop quite as far down as flaps, but they still help improve lift at lower airspeeds.
Going in the other direction: linking flaps to ailerons- to improve roll rates - is more complex. First, because they are farther inboard, flaps contribute a lot less to roll. Secondly, matching aileron deflection to flap deflection to airspeed is a complex process best done by electronic fly-by-wire systems.

As for your suggestion about routing engine exhaust or turbo-charger exhaust through flaps … sure. It was standard on some Century-series fighters with very high wing-loadings (Lockheed F-104 Starfighter and the Bristol Buccaneer). Starfighters had such tiny wings that they needed blown flaps to allow them to land on regular runways. Buccaneers needed small wings for high-speed flight through low-altitude turbulence, but still needed plenty of lift to operate from short British aircraft carriers.

We will also see blown control surfaces on the next generation of stealthy drones. Blowing air over one side of a control surface is almost as effective as deflecting/turning a control surface. Blown control surfaces only need hundreds of tiny holes, which are much easier to conceal than large hinge gaps.