1955 Pontiac Chieftain 4-door Sedan

"Here's Pontiac's 'challenge' line for 1955 – the exciting Chieftain 860, loaded with all-new looks, luxury and power – and priced to challenge the entire field. For how very few of your dollars it takes to step up to big-car quality like this! And look what they buy: Important extra wheelbase – 122 steadying inches of it. Fine-car length and breadth and sweep and style – Silver Streak style! The surge and might of 180 Strato-Streak V-8 horsepower! The warm, friendly feeling of confidence you'll develop for the day-in, day-out dependability of your car – for it's a Pontiac! And that means the little extra you invest will come back – with interest – next time you trade. It's almost sure to be for another Pontiac. For driving this proud beauty is good economy . . . and pure pleasure, too!"

1955 was a good year for General Motors: the newly introduced Chevrolets hit the market like a bomb, counting for almost 20 percent of all car sales in the U.S. at year's end, and all GM divisions could report record production numbers. Pontiac had introduced a completely new lineup, too, and the cars looked genuinely good. But the real changes happened under the hood and in GMs offices, as two long-established rules were broken in that year.

First, Pontiac's tried-and-trusted inline Eight cylinder engines were replaced with a modern V-8 in 1955. Assistant engineer Clayton Leach had developed a new "Ball-Pivot Valve Train" for this engine, that was much lighter than the conventional overhead valve gear with push rods. While it had been a common practice at GM that the divisions were granted exclusive rights of their inventions for the first year in production, this new layout was so convincing, that it was decided that Chevrolet's new V-8 would receive Pontiac's new technology, too.

Second, since the 20s, the GM-divisions had been positioned to seamlessly cover all levels of customer wealth, with no competition between the brands. The idea of "a car for every purse and purpose", as chairman Alfred P. Sloan had declared it in 1924, was simple, but clever: customers should be able to climb a "ladder of success" and buy cars from differently priced GM brands as their aspirations and wealth changed with their age, and this without ever leaving the GM "family". In this hierarchy, Oldsmobile played the role of the sporting innovative brand, being placed between Pontiac and Buick.

But now, Pontiac started to step into Oldsmobile's territory, and the powerful 1955 models were the first proof for that. Suddenly, GM had two sporty brands in its portfolio. When Pontiac's new boss Semon "Bunkie" Knudsen was appointed in 1956, this momentum should pickup speed. Being a real petrol-head, he was determined to change Pontiac's traditionally stodgy image towards much more sportiness. The 1957 Pontiacs should show first results of his idea: the traditional "Silver-Streak" chrome stripes disappeared, being replaced by jet-age side decoration. Still, Pontiac shared GMs "A-body" with Chevrolet, but already 1958 would bring distinctive looks to Pontiac's sporty lineup.