The block is designed for the Echo 23.6cc engine. I doubt it would fit other brands. One would have to have one in hand and check all sizes, clearances, etc. to see if it could be modified to work with something else.

For one thing, a lot of the other engines have a cantilevered crank that would be tough to join with another crank. The Echo engines have a crankshaft with a shaft and bearing on both ends of the crank.

AV8TOR