Far as I know Super Tiger do not make 4s, maybe you mean Thunder Tiger.. Any way, like others said the counter rotating is not necessary, a little out thrust as stated is best. Now I must say the P 38 is a snapper on an engine out. If it is the Nitroplanes one you have, it is not as bad as the Wing Manufacturing but it will snap if you make a wrong move on an engine out. I fly the Wing Manufacturing A26 which is not as bad as the P38. My buddy had the P38, his first engine out went fine and he got laxed on the second and guess what happen? Yep the duck spiral. There is a video on Youtube of a Nitroplanes 38 in a spin when one engine quit. So I know they do. All the 38s do. Just some are worse that others. I had the Nitro 38. Sold it because I hated the way they have the wing set up, makes for a carriage so you don`t mess up the horizontal stab when transporting and I did not like it enough to mod the wing. Too much work.
Now the engines will fly it, but depends on how your weight comes out, you might be in a struggle if an engine goes out. Hope your left thumbs are tuned very well because it will be busy.