THE EXPERIMENTAL GENERAL MOTORS V8 SO POWERFUL IT WAS NICKNAMED "THE KILLER"

From the very early 1960s, the American muscle car competition was extremely fierce. Each automaker was hard at work trying to out-do one another at every turn. Even General Motors subsidiaries, such as Buick, Chevrolet, and Pontiac were fiercely competing with one another in a quest for ultimate muscle dominance. Very few things were off the table in terms of rules of engagement.

Another automaker involved in the muscle wars was Oldsmobile. Their entry, the 442, was regarded as one of the top contenders. In its most powerful iteration, the 442 W-30 received a 455-CID Oldsmobile "Rocket" V8 producing 370 horsepower and 500 lb-ft of torque, not a slouch by any stretch and one of the most torque-laden engines GM ever produced. However, in the late 1960s, Oldsmobile engineers were hard at work creating an engine that would come to be known as "The Killer."

The Killer And The Reason For Its Birth

Olds Experimental "Killer" V8 Quick Facts

• Based on the existing 455-CID V8
• Only two examples were produced
• Carried the codename "W-43"
• One example is currently installed in a 1970 Oldsmobile 442 W-30

The muscle car development race in the 1960s and early 1970s made for one of the most competitive eras in American automotive history. Oldsmobile, whose 442 was an impressive car, was still relatively obscure compared to iconic muscle cars such as Pontiac with its GTO and the Chevrolet with the Chevelle. Oldsmobile saw an opportunity to blow the competition away and tried to make that dream a reality.

The thing was, back in the muscle car days, General Motors had an edict that banned the use of multi-carbureted engines in anything but the Corvette. This was done to prevent other brands under the GM umbrella from making a car faster or more potent than the most powerful Corvette on sale at the time.

So, Oldsmobile took the edict literally. The resulting idea was to be called the W-43, an experimental engine design based on the existing Olds 455-CID Rocket big-block V8. Of course, it didn't have a multi-carbed design (there was reportedly a multi-carbureted design prototype, but it was never used). Instead, Oldsmobile engineers decided to get creative with the 455 CID's cylinder heads, making more power without resorting to gigantic carburetors, or multiple ones.

The answer Oldsmobile engineers came upon was to create cylinder heads with four valves per cylinder, something that wasn't really heard of outside of motorsport at the time.

How Oldsmobile Did It

As you may have guessed, specs regarding the extremely rare W-43 V8 aren't easy to come by. However, we do know that it made 440 horses in, reportedly, a very conservative state of tune, although there were whispers the motor could create up to 560 horsepower, but these claims have not been backed up by actual facts or legitimate testing. However, even making 440 horses was impressive for the time, as very few muscle cars could compete with that figure.

In essence, Oldsmobile borrowed a tried-and-true cylinder head design from diesel engines of the time, as the four-valve cylinder head used by Oldsmobile closely resembled those found in Cummins and Detroit Diesel engines. Increasing the amount of air-fuel mixture you can force into a combustion chamber by adding valves can increase power, which is why more valves typically equal more power. That's an oversimplification, as there's more to making power than the number of valves, but it is one way manufacturers can increase output.

On top of the revolutionary heads, Oldsmobile also tweaked the engine block. A new, four-bolt main cap was installed, and the spark plugs were located smack-dab in the middle of the valve covers. This spark plug location is what sparked rumors that the Olds W-43 was actually a Hemi, but it wasn't.

Because of the altered dimensions of the W-43's new cylinder heads and the stock configuration of the W-43's block which was taken directly from the existing 455 CID Rocket V8, engineers found a problem with the W-43's pushrod angle, which was too drastic when the pushrods went to open the lifters. The resulting solution was to cast new, slightly raised camshafts to offset the high angle. The pushrods themselves - also borrowed from the 455 CID engine - were thickened from 5/16 of an inch to 3/8 of an inch to better cope with the W-43's increase in power over the standard 455 CID Rocket V8.

Reportedly, an all-aluminum version of the W-43 was in the works codenamed "OW-43". However, this engine never came to be produced and remained on the drawing board. A hugely experimental 32-valve, quad-cam version was also discussed, but it, too, never made it past the design phase.

Why We Never Got To See A Production W-43

In 1971, the US government released the first of many restrictive emissions laws that would end up choking out the American horsepower wars for a few decades. Because the W-43 engine was still squarely in development, any hopes of actually putting the experimental engine into production were snuffed out almost overnight. Of course, big blocks were still produced, but the days of 300 or 400-horsepower big-block V8s were, largely, over.

The W-43's story doesn't end there, though. As of this year, two guys named James and John Kryta from Romeo, Michigan got their hands on one of the two unfinished W-43 engines and finished its construction. Once completed, the pair took the motor and dropped it into a 1970 Oldsmobile 442 W-30, effectively creating a factory W-43-code 442. As for the other W-43 block, its whereabouts are still unknown. Who knows, maybe the lost engine will also get fixed and be placed in another Oldsmobile. We can only hope, right?

Sources: Hagerty.com, MacsMotorCityGarage.com, StreetMuscleMag.com, Hemmings.com

2024-11-27T06:22:52Z