is a computerized fuel metering system designed to deliver fuel more effeciently
than a carburator system.
The 454SS (And Chevy trucks alike) use the EFI. The EFI System uses a throttle body
to deliver the fuel in precise, metered amounts. The throttle body recieves input
from the Electronic Engine Contols and delivers the precise amount of fuel required
into the intake manifold.
in contrast, a carburator mechanically delivers fuel in relation to the load and speed
of the engine. It is more difficult for a carburator to adjust quickly and effeciantly
ti different variables, so perfect carburation is difficult to maintain.
7.4 liter (V8) w/EFI
This engine was installed in the 91 454SS and also 3500 and selected 2500 series
Chevrolet trucks with single rear wheels. New to this engine in 91 were new intake
valves and new transmission cooler line brackets for improved reliability.
Engine ordering Code L19
Bore and stroke (in.) 4.0 x 4.25
Compression Ratio 7.9 to 1 SAE Net Horsepower at RPM 230 @ 3600
SAE Net Torque (lb-ft) at RPM 385 @ 1600
7.4 Liter 255HP @ 4,000 rpm 405 Lb of torque @ 2400 rpm
400 and 4L80E transmission