1988 - 4.3 L Vortec 4300 V6, TBI, 150 hp (112 kW)/230 ft.lbf (312 Nm) (VIN Z)
1989-1992 - 4.3 L Vortec 4300 V6, TBI, 160 hp (119 kW)/230 ft.lbf (312 Nm) (VIN Z)
1990-1993 - 2.5 L Tech IV I4, TBI, 105 hp (78 kW)/135 ft.lbf (183 Nm) (VIN A)
1992-1993 - 4.3 L Vortec 4300 V6, CPFI, 195 hp (145 kW)/260 ft.lbf (353 Nm) (VIN Z)
1994 - 2.2 L L43 I4, MPFI, 118 hp (88 kW)/130 ft.lbf (176 Nm) (VIN 4)
1994 - 4.3 L Vortec 4300 V6, CMFI, 195 hp (145 kW)/260 ft.lbf (353 Nm) (VIN W/Z)

They have had different versions of the 4.3 since 1988. I had a 1994 Blazer with one and they were in alot of older S-10's.

L8r,

Kevin