Which torpedoes sank Blanco Encalada?

Were the torpedoes used against Blanco Encalada the earlier flywheel type?

No. The attack used later 14-inch Whitehead torpedoes, carried by Condell and Lynch.

The weapons were 14-inch Whitehead torpedoes carried by the torpedo boats Condell and Lynch, not the earlier flywheel type. Each boat had several tubes and carried weapons representative of the 1890 generation. The attackers still needed a merchant steamer to help them reach the target area, which underlines their limited independent endurance. Blanco Encalada's small watch and late detection at about 500 yards turned those limitations into a successful harbour attack.