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43l vortec engineThe 4.3 Liter Vortec engine is built by General Motors. This is a V6 engine that has had a long history, although much has changed along the way. The 4.3L Vortec built today is certainly significantly different from the original Vortec first offered in the mid-1980s.

The list of cars that have used the 4.3L Vortec is a long one. This engine has been in offered and most of the truck and van applications from the mid-80s to present day.

It was also offered in a line of cars in the mid to late 80s, including the Impala, Caprice, El Camino, and Monte Carlo, just to name a few.

4.3L Vortec V6 Engine Specs LU3 EcoTec3 LV3
Displacement (cu in / cc): 262 / 4300 262 / 4300
Horsepower: 195 hp @ 4600 RPM 285 hp @ 5300 RPM
Torque: 260 lb.-ft. @ 2800 RPM 305 lb.-ft. @ 3900 RPM
Bore and Stroke (in / mm): 4 x 3.48 / 101.6 x 88.4 3.92 x 3.62 / 99.6 x 92
Compression Ratio: 9.2:1 11.0:1
Fuel Delivery: Sequential Fuel Injection Direct Fuel Injection with Active Fuel Management
Ignition System: Direct Composite Distributor, Platinum-Tipped Spark Plugs, Low-Resistance Spark Plug Wires Coil Near Plug, Platinum-Tipped Spark Plugs, Low-Resistance Spark Plug Wires
Valvetrain: OHV OHV, 2 valves per cylinder, variable valve timing
Block Material: Cast Iron Cast Aluminum
Cylinder Head Material: Cast Iron Cast Aluminum
Emission Controls: Three-Way Catalytic Converter, Exhaust Gas Recirculation, Positive Crankcase Ventilation, Evaporative Collection System Close-Coupled Catalytic Converter, Quick Sync 58X Ignition, Returnless Fuel Rail, Fast-Response O2 Sensor
Engine Oil (qt / L): 4.5 / 4.3 6 / 5.7

The original 4.3L Vortec from the mid-80s, first offered in 1985, until the mid-90s was available in Chevrolet and GMC full-size trucks, G-series vans, Chevrolet Astro vans, GMC Safari vans, Oldsmobile Bravada, GMC Jimmy, Chevrolet Blazer, Chevrolet S-10, and GMC Sonoma for truck applications.

During this time range it was offered in cars in Chevrolet Impala, Caprice, El Camino, and Monte Carlo. It was also offered in Pontiac Parisienne and Grand Prix, with an additional application in the GMC Caballero.

After a major change to air flow performance in the mid-90s, the newly designed V6 Vortec went into many of the same truck and van applications as the previous 4.3L Vortec but was then also added to the Chevrolet Silverado and GMC Sierra.

The early 2000s saw another major modification to this engine, with multipoint fuel injection being added. This resulted in 6 fuel injectors on the engine, one for each intake port. This engine also replaced the previous generation engine in the aforementioned truck and van applications.

The most recent change to the 4.3L Vortec came in 2014, called the Gen V of the V6 engines, and this is now available as the base model for Chevrolet Silverado and GMC Sierra trucks.

The 4.3L is a good compromise between power and fuel economy, especially in smaller truck applications. It also has the added advantage of costing less than the V8 option.

4.3L Vortec Performance Specs

When talking about engine design, power and displacement, this engine must be broken into 2 separate groups, the engine from 1985-2009, and the latest offering introduced in 2014. The initial launch of the engine came with a horsepower rating of 155 at 4000 RPM and peak torque of 230 lb-ft at 2400 RPM, achieved with an engine designed with a bore of 4.00 inches and a stroke of 3.48 inches.

By the time this version of the engine was phased out, it was able to achieve 195 horsepower at 4600 RPM and 260 lb-ft of torque at 2800 RPM. This is not an overwhelming amount of power, but is in line for a 4.3 liter, 262 cubic inch engine.

The newly introduced 4.3L Vortec, also 262 cubic inches, has a different layout with a bore of 3.92 inches and a stroke of 3.6 inches. The engine has a peak horsepower of 285 at 5300 RPM and peak torque of 305 lb-ft at 3900 RPM.

Head and Block Construction

The original 4.3L is constructed of cast iron block and head. The valve train for this engine is conventional pushrod overhead valve (OHV) with 2 valves per cylinder. Many of the other materials used varied considerably during this long span.

The recently released 4.3L is made of aluminum alloy head and block, although it continues to use the conventional OHV design with 2 cylinders per head.


The 4.3 L Vortec is a traditional engine that General Motors has been producing since the mid-1980s. Much of the same base design was kept until the late 2000s. Anytime this type of base design and family can be carried on for more than 20 years, it is certainly impressive.

The latest version of the re-designed 4.3 engine certainly offers more power than the traditional 4.3L, and may be more enticing now that it has more power to do various jobs, but still offers fuel economy improvements in comparison with its V8 counterpart.