I'd like to know more about these "semi-sanctioned" tweaks that were done on P-47s. For years I've heard stories about crew chiefs "souping up" their pilot's aircraft, keep in mind that as a maintainer then and now, there's a limited about of things you can do legally to an aircraft to enhance performance. I've heard of waxing and limited use of body filler, but both process are time consuming and if there's a big push to support an operation, I don't see any Tech Sgts wasting the time and energy, especially if they and their "troops" are assigned to 3 or 4 aircraft, which from what I understand was very common during the mid/ late 1944 period in the ETO.
Now, mentioned Robert Johnson, here's a quote from him concerning his crew chief Pappy Gould
"R.Johnson--Sure. My second Jug, a D-5 was the best P-47 that I ever flew, and I flew them all, including the P-47M which the 56th got near the end of the war.
CCJ: What made this one Thunderbolt so fast?
RSJ: Several things. My crew sanded every joint smooth, and waxed it to a high gloss. Factory technical reps showed my crew chief, Pappy Gould, how to adjust the wastegates to keep the boost pressure higher than normal. My D-5, which I named Lucky, had water injection. I never used the water injection in combat. I didn't need it. From time to time I'd switch it on, push the throttle up to 72" of manifold pressure and the head rest would smack me from behind. I would let her run for a few minutes just for the fun of it."
Notice how the "tweaks" came at the direction of factory reps (and probably had a squadron maintenance officer's approval).
P-47 engine performance was discussed in this earlier thread;
http://www.ww2aircraft.net/forum/av...s-engines-need-some-clarifications-34328.html