Blazer Forum - Chevy Blazer Forums

Quote:

ORIGINAL: LoLoS10Blazer87
Fuel delivery with the Vortec is more conventional, with 6 fuel injectors instead of one.

This sentance is only correct for the '96-'03 4.3L vortec CSFI motors.

Found on another website:

Quote:

VIN W, RPO L35:
Central Port Injection (CPI/CMPI). Manufactured from 1992-1995. It has central injection assembly mounted in the intake manifold which uses a single batch-fired injector feeding 6 poppet nozzels located at the intake ports. It has a dual-plenum manifold (upper and lower) with variable tuning with a manifold tuning valve to equalize pressure. The manifold looks much like that of an LT1, the throttle body is at the front of the manifold and goes to an intake tube with a filter box behind the left headlight. Vortec is written in orange on top of the plenum, which is black or aluminum colored.
190 to 195hp, 260ft/lbs

VIN W, RPO L35:
Central Sequential Fuel Injection (CSFI), Sequential Fuel Injection (SFI). Manufactured from 1996 to 2003. CSFI uses six individual injectors and a fuel pressure regulator that pulses fuel through six orifices through flexible nylon tubes. These tubes run to poppet valves at the intake ports. Manifold setup is similar to TBI, except it has one bore and one throttle blade. Air filter box is located behind driver?s side headlight.
180hp, 245ft/lbs (2wd pickups), 190hp, 250ft/lbs (Blazers and 4x4s).

In 2004, GM changed the configuration of the CSFI spyder to include 6 injectors at the ports and called it SMPI, but used the same spyder body. This removed the poppet valves used in the CSFI and the SMPI is, as I understand it, compatible with the earlier CSFI engines.

More to the point of the last post here. The only way to tell if they would work would be to match up the head gaskets, measure deck heights, bolt them up to a test motor, etc. All of which needs to be done way before thinking of running a motor with them. Things to look for are the correct alignment of coolant passages, piston to valve clearances, alignment of the intake manifold runners and coolant passages, etc. There are too many items to list, but if you had a good set of tools and some time, you could go to a junk yard and do most of the comparison yourself on engines in the yard.