Milestone Engines: Chevy 265-cid V-8
In 1974, Special-Interest Autos magazine asked Cole if there was any major breakthrough in the 265's design. Possibly, Cole said, it was "when we decided to make the precision cylinder blocks - the heart of the engine - by using an entirely different casting technique. We used the green-sand core for the valley between the bore. That is, for the 45-degree angle center, 90 degree total, we used a green-sand core to eliminate the dry-sand core, so that we could turn the block upside down. We cast it upside down, so the plate that holds the bore cores could be accurately located. This way, we could cast down to 5/32nds jacketed walls."
In the same SIA article, Harry Barr pointed out certain advantages of the Chevy 265 over the '55 Pontiac V-8:"...their design was heavier than ours. But they developed a sheetmetal rocker arm that we thought had possibilities. It hadn't been decide yet, but we jumped into that, and gave it to our manufacturing group. They determined that they could make stamped rocker arms with no machining whatever - just a metal stamping.
"We also lubricated it differently from Pontiac...with the oil coming up through the tappet, up through the hollow pushrod into the rocker arms, then over to lubricate both the ball and the pallet of the rocker arm...These were all new ideas, and very good as far as automation was concerned. You never had to screw anything - just press these studs in."
Actually, the 265 was Chevy's second V-8, the first being the disastrous 1917 design. But this one was near-perfect. Overhead valves, high compression, light weight, and oversquare dimensions (3.75 x 3.00) made it efficient and powerful. Some 43 percent of 1955 Chevy's were equipped with it - amazing for a make which hadn't offered a V-8 within recent memory. Horsepower was 162, or 180 with "Power Pack" (four-barrel Rochester carburetor and dual exhausts, available on all models except wagons). In basic form, the 265 was both more potent and more economical than the rival Ford 262 or the Plymouth 260, and outsold them easily. It had plenty of development room, too. For 1956, Chevrolet offered 205 - and 225 - bhp versions using four barrel and dual four-barrel carbs, respectively.