Comparing the 109 to the F4U falls right into my sweet spot as they are the two I'm most familiar with, particularly the 1a and the G2. As everyone else has said keep the fight in the verticle. A hog coming into a fight at 300mph with a competent F4U pilot can pull a full immelman twice and after that is done in the verticle as they are now at about 100mph. The G2 coming in at the same speed can pull the same move and come out at about 125mph. Now here's where the big diference comes in. The G2 can drastically out accelerate a 1A from these low speeds. Either plane can get back into a verticle turn around 150mph, but the G2 gets to this point from that low speed quicker. The F4U has to either flat turn back towards the G2 or give up it's 6 until it has enough speed to vertically turn back into the G2. In either case the Hog has gone from a nuetral fight to defensive as it either has the G2 above it and behind with the F4U slight speed advantage, but positionally in a bad spot, or below the G2 co-E. This is basically 3 merges and a G2 advantage. This is my text book me flying a G2 or later 109 vs a F4U. The key to ending this fight with the G2 is to not get suckered into a rolling scissors with the 1a, you won't win it with a good hog stick at the wheel. He wants you into a rolling scissors to reverse the fight. Once you see the fight going that direction, vertically seperate and re-engage.
With the pony your options are a bit less since the turn performance difference at lower speeds are quite significant. Best advice there is come into the fight with a ton of smash, use that top speed to your advantage. On the second merge out verticle the F4U and get yourself a high perch in which to fight from. use the F4U as your hard deck and turn it into a BnZ fight from there. Done correctly your pony will be in little danger, but beware of the hog acting like it's low on E but secretely building it up. I often sit low on an attacker circle climbing above me, trying to bleed all my E out. All the meanwhile I've sucked almost all my flaps in and keeping enough E that I can pull into and come over the top of him as he pulls down on me. Kinda like a Barrel roll defence but from a head on opponent. As I roll over the top of him as he comes down, I'll get position behind his 3/9 line, as I'm slower and have a smaller turn radius, he'll have a lot more speed on me but he'll have to trade that in order to get position again. the trick for me is to roll on them quick enough that they go defensive and try to dive away, which puts the ball firmly in my court.

BigRat