P-38? I missed the twin-tail devil! Designed by Kelly Johnson (the guy who also was responsible to the F-104, U-2, and SR-71) the Lightning had twin Allison engines, four .50 cals and a 20MM cannon. It was bad to the bone, just ask Yamamoto. Oh wait, you can't, he's dead! Got smoked by a P-38 Lightning!
"Glacier Gal" was the P-38 dug out of a glacier in Greenland. It was restored in about 10 years and was at an air show in 2004 at Langley AFB. It sounded like the baddest hot rod ever. The P-51 with the Rolls Royce Merlin (also built by Packard) engine had a very unique, very classic sound. The P-38 just sounded bad ass!
If memory serves the port engine rotated in reverse to counter the torque roll. Those are the engines they ran in land speed cars and dragsters.
Yes they packed a deadly punch. A few were equipped with a cannon (yes a real cannon) for anti ship duty.