Probably the most popular pickups ever produced are the '73-'87 Chevrolets. Classic styling and solid drivetrains are found in most of these rigs, and parts interchangeability is among the best of any vehicle line. Of course, these pickups do suffer from more than a few common maladies, but some years are better than others. In this story, we'll clue you in to what you should look for when buying one of these examples of honest American truck-building.
The wide range of engines used is second only to the variations in compression and horsepower figures. In addition, not all engines were available in all of the weight ratings during all years. We've compiled a fairly comprehensive list of engines, but strange variations exist in the real world. As the EPA mandated better economy ratings and phased out leaded gasoline and California threw its regulations into the mix, compression ratios and power figures generally dropped, then started to rise as the technology improved to make these motors work almost as well as they used to. For instance, the lowly 305 of 1978 had a lame 8.4:1 compression ratio and is generally regarded as a poor performer. But by 1987, the little mill featured a 9.2:1 ratio, a 20hp gain, equally improved torque figures, and much better fuel economy.
The small-block 350 powered...
The small-block 350 powered most Chevys and is a popular motor for modifications and buildups.
The 305ci and 350ci small-blocks appear identical to the untrained eye, but the two or three stamped letters on the block in front of the passenger-side head above the water pump mounting can identify the displacement, but you may need a book that translates the code. If the motor is an '80-or-newer, the displacement is cast into the back of the block near the bellhousing mounting flange. The 350 is the 5.7L and the 305 is the 5.0L.
The "standard" pickup is somewhat of a misnomer; so many options and styles were produced that the standard two-door cab with a Stepside bed is simply one of many styles. Two basic body designs were available: the '73-'80 with square hoods and fenders, and the '81-'87 sloped-nose style. Spotting weight ratings was simple back then: ½-tons were K10s, ¾-tons were K20s, and the ¾-tons were K30s. The exception was in 1987 when they changed the K to a V, a prelude to the massive body and mechanical changes of the '88 model year. Beds came in long and short with either the Fleetside or Stepside design, though shortbeds were used only on K10s. The "Big Doolie" with dual rear wheels was introduced on the '77 K30 truck. In addition, the Crew Cab and Bonus Cab was offered on the K30--the Crew Cab had rear seats and the Bonus Cab had only an open storage area. A factory extended cab was never available with the '73-'83 trucks.
Trim levels started with the Custom and ended with the Silverado package with all the options and goodies, but the basic mechanicals stayed the same. However, the weight ratings were more of a factor in model availability, as K10 models never received a dualie or Crew Cab configuration. And all of the styles had little relation to the two-wheel-drive options, as C30 pickups with 454 power were available long before the big-block K30 made the scene in 1977.