No 318 LA was externally balanced. That's mis-information that's been floating around for some time. I don't know who started it but they were WRONG. Even if a 318 was externally balanced it probably wouldn't require the same amount of balance weight a 360 does to balance it. Some 440's were externally balanced yet you just can't swap 440 and 360 externally balanced converters. There's only 20 grams of difference in the balance but it's enough to cause damage to the engine bearings.