Both of these planes will out turn a K4. Both are nearly as fast. The La7 is faster. The KIa4 can keep up and climb with a K4.
Set up the merge or reversal so that you can get closer even if you have no shot. Just get close. Close on the merge pass, close on any turn.
Once you get close try to turn into them and roll over the top then wep on and try to get a shot. Try to create a scissor type shot. You want them crossing your guns as much as possible.
Avoid any sustained flat turns. Often the LA and KI will make large arcing turns at high speed and slightly climb in the turn. Then they will reverse and keep the speed. You lag out on the turn and keep your speed and when they reverse the turn you go strait up to stall and come back down. If your off and they follow you up just go level some, use flaps and avoid the guns, and dive into verticle scissors down and work for an overshoot. Then escape out the opposite way, get some speed and turn back as fast as you can. Re engage.
Try to keep your turn circle and their turn circle crossing at 45 degree angles...or crossing obliquely as much as possible. If the circles begin to cross more horizontal or verticle with no seperation you will get out turned quickly especially if they are fast. If you keep the turns to them off angle at 45 degrees you are essentially in a scissor situation which is what you want because you will get good snapshots as they pass under or over you.
Oh and try to keep your nose UP on every turn.....unless you need to dive out and escape. If you start turning nose down to cut the turn you will get too fast and overshoot allowing them to simply roll over and shoot you.
Good Luck