The year 1971 saw only subtle differences in the Chevelle body, but in previous years, the SS396 and SS454 options were performance-oriented and included either a 396ci engine or a 454ci engine. Unfortunately, Chevrolet dropped the RPO Z25 SS396 option and changed the 1970 RPO Z15 SS454 option to the Z15 SS Equipment Option.

What this meant for the 1971 Chevelle is it became more of a dress-up option than a performance option. The SS option was available on only the two-door Malibu sport coupe, convertible, and El Camino bodies.

This year GM informed all divisions that all engines sold must run on unleaded fuel. This edict was in regards to tightening CAFE standards and caused a serious detuning of all the engines found in 1971 Chevelles. Buyers could get their 1971 Chevelle with either the only available six-cylinder–the 250ci inline engine with 145 horsepower, or the standard V8, which was the 307ci engine that delivered a sleep-inducing 140 horsepower.

That’s right, the V8 had five horsepower less than the six cylinder engine. By upgrading the small-block V8 engine options, this allowed buyers to order either the 245 horsepower L65 350ci engine with a two-barrel carburetor or the 270 horsepower L48 350ci engine with a four-barrel carburetor.

The “entry-level” big block was the LS3 402ci engine with a four barrel. This big block was actually a 402ci engine, but was listed as a Turbo Jet 400. Finally, the LS5 454ci engine with a four barrel carburetor was the only 454ci engine available. Unfortunately, the LS6 was gone. Any of these engines could be ordered with the buyer’s choice of any four-speed manual or three-speed automatic transmission. Just as an aside, the 307ci engine could not be ordered with the SS option.

We also need to help alleviate any confusion by letting you know that in 1970, Chevrolet introduced the 400ci Turbo-Fire small-block engine. The Turbo-Fire 400 (LF6) was not available in the Chevelle. The small-block 400 was only available in full-size Chevrolet cars and the Monte Carlo.

Although both engines were occasionally referred to as a 400, the Turbo-Jet actually displaced 402 cubic inches, and the Turbo-Fire displaced 400 cubic inches. Needless to say this caused some confusion at the time, as many people didn’t understand the Turbo-Jet (Mark IV big-block) and the Turbo-Fire (small-block) designations.