There weren’t many changes to the body of the 1972 Chevelle from the previous year. Up front, the front parking/marker light on the fenders saw the divider bar removed, making it one large lens. Even so, the 1972 Chevelle still had great appeal to buyers and was available as a convertible, hardtop, sedan, and station wagon.
Under the hood, several drivetrain combinations were available for a 1972 Chevelle customer. The base engine power could be delivered by either the one available 250ci six-cylinder engine with a tire smoldering 145 horsepower, or the even more anemic 307ci V8 engine with a measly 130 horsepower. It was apparent that the muscle car wars had ended. If you needed more than the base engines could offer, you could upgrade to optional engines including the 160 horsepower 350ci engine with a two-barrel carburetor, or the 175 horsepower 350ci V8 with a four-barrel carburetor. Eclipsing that was the 240 horsepower 402ci (still called a 396). This would be the last year that a 454ci engine would be available in the Chevelle, where that engine managed to put out 270 horsepower. Any 1972 Chevelles that were sold in California could not get the 307ci V8, so a 350ci engine was the base engine instead.
All horsepower ratings were changed to the “net” way of measuring as opposed to the “gross” unit of measurement. Before 1972, most engines were rated by SAE standards J245 and J1995. This calculated the output of a bare engine on a test stand with no accessories, free-flowing exhaust headers, and optimal ignition timing. In 1971, manufacturers were building engines with lower compression ratios and were detuning their engines in preparation for the advent of unleaded gasoline.
For this reason, U.S. manufacturers felt that it was time to discontinue the use of the gross rating system. In its place, they began using the SAE “net” rating system J1349. While net horsepower ratings are still made on a test stand, the test is done with stock ignition timing, carburetion, exhaust, and all accessories in use. In short, the engine is run like it is installed in the car. The result of the new net rating system advertised a dramatic drop in advertised power.
When it came to transmissions, all models were available with either e three or four-speed manual transmission, and the automatic choices were a Powerglide or one of the two Turbohydro three-speed automatic transmissions.
This was the last year for the cowl induction hood option for the Chevelle, and it wasn’t even mentioned in sales brochures.