What Engine Came In The 1978 Pontiac Grand Prix & How Much Is One Worth Today?

The Pontiac Grand Prix made its first appearance in the American automaker's lineup in the early 1960s. In its earliest years of production, it was considered one of the manufacturer's more underrated muscle car builds, boasting sleek lines and proper V8 Pontiac power under the hood. The Grand Prix continued to rank among Pontiac's more under-the-radar muscled-up builds for most of the decade, and even into the 1970s. Throughout the '70s, however, the Grand Prix began a wild transition from sleek coupe to the boat-sized behemoths that were hitting the road in the latter part of the decade.

Though almost absurdly large, the stock V8 engines ensured those early-to-mid-'70s beasts were still pushing proper muscle car power. However, the Grand Prix received a dramatic facelift in 1978, with Pontiac finally reigning in the comically oversized approach to the vehicle, trimming more than a foot from its length and over 600 lbs. from its overall weight. Perhaps not surprisingly, the downsizing of the Grand Prix did not stop with the build's body size, with Pontiac also making an under-the-hood change by nixing the V8 engine as a standard option.

Pontiac's engineering team instead opted to make its 231ci (3.8 L) V6 engine standard in base models of the Grand Prix build. Drivers could still upgrade to Pontiac's 301ci V8 engine for an additional cost, with the vehicle's base V6 reportedly capable of delivering around 105 hp and the V8 upgrade pushing the ponies to between 140 hp and 150 hp.  

Despite the major downgrade in muscle, the 1978 Pontiac Grand Prix was still pretty powerful for a coupe in its class. Of course, those horsepower numbers are a far cry from the 300 to 400 hp that some of the early 1960s Grand Prix builds were pushing, and even shy of the 185 hp of the massive mid-70s models. One can, of course, posit that Pontiac's hands were a little tied in the mid-to-late '70s due to the decade's devastating energy crisis, and you can likely chart the Grand Prix's general decline in power to the onset of higher gas prices and fuel shortages.

Whatever the case, the boxier, powered-down versions of the Grand Prix builds that showed up in '78 are arguably less revered than many models that came before and after. It should come as no surprise then that the vehicles aren't quite as sought after on the resale market as some of their predecessors.

For point of reference, Hagerty claims that a base model 1962 Pontiac Grand Prix in good condition could net you around $37,000, with Classic.com noting the average value at just over $30,000. Per Classic.com, the resale numbers for the '78 Grand Prix are significantly lower, with the site noting the average value at just over $13,000. Classic.com claims $22,000 as the top resale number for a '78 in the past few years, though it's worth pointing out that the $22,000 sale was a Grand Prix with the more desirable 301ci V8 engine. Nonetheless, those resale values are good enough rank the '78 era vehicles well above several other generations of the Pontiac Grand Prix.