All is not necessarly lost. Without knowing for certian you probably have bent a valve or two when the cam stopped moving when the timing chain broke. On almost any motor when a valve is fully open it will contact a piston if the cam is not moving and the piston is moving. With the factory forged pistons they should not get too damaged, and stock valves are pretty cheap.
Finding out why the chain broke may be more tricky, just broke?? Stuck valve, lifter or spun cam bearing? I would pull the heads and inspect the valves and pistons, check for bent pushrods or damaged rocker arms. Try to spin the cam and look for signs of trouble, if no problems seen, just replace the bent valves and new timing chain and front cover.
If the cam does not turn freely simply going to a new short or long block may be easier than fixing the problem since something is obstructing the cam and sending metal through the motor etc.
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Frank W
90 5.0 LX coupe Daily driver. Silencer removed, K&N filter. Flexalite fan, 3 core radiator. FMS flywheel and Clutch, FMS blue wires Energy Suspension end links
88 Notch 2.3L 5 speed Parts/beater car
My two Notchbacks
74 Chevy Laguna Type S-3 305 Finally fixed getting a 454 to put in garage
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