The Carburetor Version

• The carburetor version of the 4.3-liter engine, the LB1, used a two-barrel carburetor for induction. Chevy used the engine as its base engine in its C/k line of pickups from 1985 to 1986. Chevy rated the 4.3-liter engine at 155 horsepower with 230 pound-feet of torque. The first Vortec engine, the LB4, with fuel injection received the same output rating in 1985 as the LB1.
  
  

The Syclone Turbo

• GMC introduced the 1991 Syclone as the fastest truck ever with a horsepower rating of 280 at 4,400 rpm with 360 pound-feet of torque at 3,600 rpm. GMC achieved this output rating by turbocharging the engine. It made these trucks as limited editions.
  
  

The Fuel Injected S-10

• In 2004, the last year of the Chevy S-10, the 4.3-liter V-6 peaked with sequential fuel injection. Chevy rated the engine at 190 horsepower at 4,400 rpm with 250 pound-fet of torque at 2,800 rpm.