Historic Chevy Performance Engines

Here's another look inside the Museum of American Speed treasure chest. This time, we've picked a few significant Chevy engines, from stock to highly modified.

Here’s where it all began for the legendary Chevy small block. After working on the Cadillac V8 project in 1949, GM engineer Ed Cole was made Chevrolet’s chief engineer and was tasked with replacing the decrepit “Stovebolt” 6. The resulting short stroke 265-incher seen here was wildly successful, and we all know the rest of the story. The Corvette became a legit sports car almost overnight. The engine was a big part of what made the ’55 Chevy car an instant classic, and its compact size and huge power potential made for a desirable swap into hot rods of all makes. If the flathead Ford V8 really launched the performance aftermarket, then the small block Chevy carried it for the next fifty years or so. Legendary models like the Rochester Fuelie, L76, and LT-1 would propel Chevy through the muscle car era and beyond. And it all started here.

One factor that made the SBC such an enduring favorite is the relative consistency from one year to the next. In general, a 70’s or 80’s small block will bolt right in where an earlier engine was. Speed parts like intakes and cams fit almost all of them. But there are little idiosyncrasies, and the early engines were full of them. The 265’s cam had a unique flat on at the rear to oil the top of the engine. Early engines didn’t have side motor mount provisions, and until sometime in ’59 the valve covers featured staggered holes instead of the symmetrical ones that most of us are familiar with. But the real giveaway on a ’55 265 like the one pictured is the lack of an oil filter. An intake-mounted accessory was the only way to add an oil filter in ’55. Apparently, the American public was just expected to change their oil a whole bunch.

Ok this is seriously cool. To celebrate their new V8, Chevy produced these beautiful cutaways for the ’55 Motorama. GM started throwing this little party for itself in 1949 as a way to show off to the public the fantastic concept cars being cranked out by Harley Earl’s Styling Section along with the newest production models. In ’53, the party hit the road and officially became the Motorama. By ’55 when these cutaways appeared, there was a Motorama in New York, Boston, Miami, Los Angeles, and San Francisco.

Special projects and show displays like this tend to have a short life. Once the engine and transmission display had been seen by a few million people, the General no longer required its services. Through some set of random circumstances, the group was kept together and discovered decades later in Utah, still housed in the original shipping crates. It was then meticulously restored by Chevrolet Creative Services before being acquired by the Museum of American Speed.

With the 265 Chevy proving itself as a legit hot rod powerplant, Chevy decided to punch the bore out 1/8” for more cubes and more power. Beyond the increase in displacement, Ed Cole and Co. had another trick up their sleeve. Fuel injection was an exotic and rare technology in the 50’s, but work on the Rochester Fuelie was underway almost before the ink was dry on the blueprints for the Chevy V8. In fact, the Museum of American Speed houses a Corvette that dates to late ‘56 that was used to test the viability of this high-tech induction on the racetrack before it hit the streets. When it debuted in ’57, Fuelie 283’s were only the second American engine to achieve the magical one horsepower per cubic inch mark.

You almost can’t stop yourself from singing the song when you hear that magic displacement figure. The Beach Boys were singing about the first big block Chevy, which offered more displacement to power Chevy cars through the trenches of the developing muscle car wars. Introduced as the 348 in 1958, the Mark I “W” engine grew to 409 cubic inches in ’62 with dual-quad versions available all the way up to 409 hp. In ’63, the double-nasty 425-horse 409 appeared still wearing those dual AFB’s, but also carrying a solid lifter cam and 11:1 compression. It became the stuff of story and song in the Biscaynes, Bel Airs, and Impalas that were tearing up the high banked ovals and dragstrips of the country. Real fine, indeed.

The ultimate “W” engine appeared in ’63. RPO Z11 got you an Impala with aluminum body panels (!) and a 409 stroked to 425 inches with an insane 13.5:1 compression ratio. Z11 Impalas also had a cool cowl induction setup just waiting to swallow up that superspeedway air. We offer these monsters up as proof that the muscle car wars were already well underway by the time the first ’64 GTO rolled off the line.

This engine made the list for several reasons. First, no list of hot rod Chevy engines should be considered complete without a big block. Second, this shows the next evolution as Chevy was seeking more cubes. Work on the "Mystery Motor" had already begun when the Beach Boys were writing about its predecessor, and it arrived in production cars in '65. We all know the rest of this story too, as legends like the L88 and LS6 have filled up the history books.

Finally, this one made the list so we could shout out Smokey Yunick. Not only was he the man when it came to putting together a rulebook bending racecar, his shop was also used as a backdoor into racing for GM engineers during the infamous racing ban. This 366 is not the tall deck school bus lump that many of us may think of, but instead a destroked 396 with 12:1 compression.

Part of the small block Chevy’s greatness comes from its near infinite capacity to be hopped up by aftermarket speed goodies. And there have been some good ones over the years. This 327 features a wild Latham supercharger.

Norman Latham started making his axial-flow superchargers in the mid-fifties. Once you get past the side draft Webers, they don’t look all that different from a Roots-style blower, but inside they’re completely different. Internal drums with sheet metal veins welded to them act like tiny turbines and spin at approximately 1 bajillion rpm. As you might imagine, they sound like a siren.

Boy if this engine could talk. The name Jim Travis is familiar to anyone who knows Bonneville and land speed racing. And the SoCal coupe will be familiar to those folks too. What do these characters have to do with this Potvin-blown small block? Well, at one time they were all together and went a blistering 236 mph at Bonneville!

Before it was restored and leading a pampered retirement, the SoCal coupe was a warrior of the dry lakes and drag strips. Once Alex Xydias and crew were done with it, Jim Travis took over and kept pushing the envelope with the ultra-chopped coupe. He went over 140 mph with a flathead before going nuts with the 300-inch Chevy pictured here.