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8 Biggest V8 Engines Detroit Ever Sold in a Car And 5 They Didn’t!

What Was The Biggest V8 Engine To Roll Out Of Detroit?

Cadillac 500 Biggest Car Engine

When in doubt, bore it out. There’s no replacement for displacement. There’s no substitute for cubic inches. Here are 5 motors where Detroit did just that.

What’s interesting is that many of these largest engine lumps weren’t intended for muscle cars – they were intended to go under the hoods of full-sized luxury cars. They’ve since become a source of cheap horsepower for drag racers and street rodders alike. So which one of these was the biggest engine in the world to come from Detroit?

The Biggest V8 Engines From Detroit!

Number Eight: Chrysler 440

The 440 CID engine was produced from 1965 until 1978, making it the last version of the Chrysler RB big block. From 1967 to 1970, the high-performance version was rated at 375 hp with a single four-barrel carburetor, and from 1969 to 1971, but with three two-barrel carburetors (“440 Six Pack” for Dodge, “440 6 Barrel” for Plymouth) the motor produced 390 hp.

For 1972 all engines, including the expensive new 440,  featured lowered compression, more conservative cam timing, and other changes to comply with tighter emissions regulations. The 1972 440 produced only 335 hp gross, and  225 hp under the new SAE net rating system.

Engine power dropped a bit each year until 1978, when it was rated at 255 hp (in police specification) and limited to large sedans and police packages.

Number Five (tie): Pontiac 455, Oldsmobile 455, Buick 455

While these are three completely different engines, it’s difficult to discuss one without referencing the others.

The first to enter service was the Pontiac, dating back to 1955 (same year as the small block Chevy). The Pontiac engine maintained the same externally dimensions through its entire life (with the exception of deck height), the last Pontiac engines were produced in 1981. The only identifier used to differentiate the smaller displacement engines from the larger ones was by crankshaft journal size. The Pontiac 455 engine featured the larger 3.25″ journals. With a longer stroke than bore width, the naturally aspirated engine was geared more to the production of low-speed torque than top end horsepower. The 1970 H.O. version of the 455 produced 370 hp but with a diesel-like 500 lb-ft of torque. To final installations were in 1976 when emissions hardware and unleaded fuel requirements sucked power down to a net of 200 hp.

Oldsmobile Generation II V8 was introduced in 1964. The “big block” version, was brought out in 1965, which shared the same dimensions as the “small block”, except for an increased deck height to accommodate a longer stroke. The ultimate version of the engine was installed in the 1968 – 1970 full-sized front wheel drive Toronado GT coupe, in its W34 form, and produced 400 hp gross. Production continued through 1976, which produced 275 hp net in its final form.

In 1967 Buick introduced a new “big block” design to replace the infamous “Nailhead” V8. In regards to bore:stroke ratio, it was the opposite of the Pontiac engine, an oversquare (large bore than stroke) design, which should be better suited to high revs and higher horsepower, usually the the expense of torque.. Oddly though, it generated 10 ft-lbs more than the comparable Pontiac and was the highest torque output of any engine in the first muscle car era. Horsepower seems strangely out wack as well, with the high-performance GSX Stage 1 package rated at just 360 hp for 1970. The last Buick 455s were manufactured in 1976, again the victim of ever-tightening regulations.

Number Four: Lincoln 460

Designed as a replacement for the older MEL 462 V8, the 460 version of the Ford “385” family of motors was designed for smooth, quiet driving (unlike its “385” brother the Ford 429) as installed in the Lincoln Continental. The engine produced 365 hp (gross), limited by its relatively small carburetor. The 460 was phased out for use in passenger cars in the late 70s, but continued to be produced with minimal modifications in trucks, RVs, and boats until production ceased in 1997.

Number Three: Lincoln 462

Despite near identical engine displacements, the Lincoln 460 and Lincoln 462 are completely different engines. The Lincoln 462 was based on the MEL engine block architecture (Mercury-Edsel-Lincoln), first produced in 1958. The 462 engine produced 340 hp and was used only in Lincoln Continentals, from 1966 until mid-year in 1968 when it was replaced by the 385-series 460.

Number Two: Vortec 8100

If you’ve been wondering where on our list the Big Block Chevy has been hiding, here it is. And since SUVs carry passenger car plates, the Vortec 8100  qualifies under our rules. Where Ford and Dodge turned to V10 designs to create gasoline-powered engines for their larger pickups, GM dusted off the 454 big block and almost completely redesigned it for Chevy and GMC trucks, vans, and Suburbans.

Chevy  retained the same bore diameter as the old 454 , but the stroke was upped by 0.37 in to reach 496 CID (8.1L). Power output was 340 hp, which compares favorably to the 1972 LS5 454 output of 270 hp (both SAE net, with the Vortec meeting even stricter emissions regulations than the LS5).

Number One: Cadillac 500

The 1960s were a horsepower war not just among muscle cars, but luxury cars as well. Cadillac had its V8, but its design limited its displacement to 429 CID, less than Lincoln and Chrysler.  As a result Cadillac developed an all-new engine for 1968, a 375 hp V8 with a displacement of 472 CID. In 1970 Cadillac raised the displacement again by stroking the motor to 500 CID. It was rated at 400 hp with a truck-sized 550 lb·ft of torque.

As emissions and mileage regulations came into effect, each passing year took a toll on the engine’s output For 1971 compression was reduced from 10:1 to 8.5:1, which dropped power to 365 hp, or 235 horsepower under the new SAE net ratings. By 1976, its final year, power had fallen to 190 hp. There was a brief reprieve with the introduction of an option fuel injection system where power rose back up to 215 hp net, however the big motor’s days were numbered and it was dropped after the 1975 model year. As one of the biggest engines of the time, and the biggest engine on the list, this one is well worth remembering.

Note: Ford did produce a Super Duty V8 (not to be confused with the Ford Super Duty model of truck) from 1958 to 1981 for medium- to heavy-duty trucks in three displacements:  401, 477. and 534 cubic inches. These were heavy, slow-revving motors designed for buses, concrete mixers, and garbage truck applications. There’s no evidence these engines were installed in any passenger vehicles at the Ford factory.

5 Detroit Engines That Weren’t For Public Consumption!

You’ve seen the biggest, but how about something more obscure like these 5 mystery muscle motors of the 1960s that Detroit never sold in a car? Overhead camshaft engines are commonplace today, but Detroit has been tinkering with OHC V8s since the ’60s. While some of the most iconic engines of all time were those that made their way into production cars of the ’60s, it’s highly likely that you’ve never heard of any of these high-horsepower beasts.

From experimental designs to beefed-up takes on existing motors, this group will surely make you wish some of these engines actually evolved into a real production engine, as each is more impressive than the last! Let’s take a look at 5 monsters never sold to the public.

1968 Ford 289 SOHC V8

Ford built three experimental 289s with a unique single overhead camshaft design that features a cam located in each of the cast aluminum valve covers (instead of on top of the cylinder heads). The lobes of each cam activate the cast iron rocker arms that open each valve. In the original camshaft position within the engine is smooth shaft whose role is to drive the distributor as well as the two overhead cams. The purpose of this project was to raise the maximum engine speed and with it peak power. The OHC 289 produced 300 HP at 6500 rpm.

Ford considered offering the SOHC conversion as a kit. But as the stock HiPo 289 already made 271 hp, and Shelby was getting 306 hp with bolt-on parts, it was deemed that this internal combustion engine was not worth pursuing.

Oldsmobile W43 DOHC V-8

As part of the development of the Oldsmobile 455, Olds engineers wanted to take the design of the engine as far as possible. The ultimate version added a set of dual overhead camshaft cylinder heads to the mighty engine. A gear drive supported by roller bearings in an aluminum gear case at the front of the motor spun the cams, while a driveshaft was used in the standard camshaft position to transmit motion to the oil pump and distributor.

Toward the end of 1969 engineers dyno tested the DOHC W43, built with a very racy12.2:1 compression ratio, and recorded a very flat (and fat) torque curve. Peak power Olds engineers recorded was 700 horsepower at close to 7000 rpm. This was achieved using the standard cam profiles for the W43, ground onto separate intake and exhaust camshafts. At that point, no development had been done to optimize cam specifications to match the breathing of the heads.

But on January 1970, General Motors President Edward N. Cole  announced that all GM divisions would lower the compression of their motors so 91 octane unleaded fuel could be used, and development stopped on the DOHC Olds.

1964 Pontiac SOHC V8

Most likely prompted by its development of the Pontiac OHC six, the GM division built three different experimental SOHC 421 CID V8  engines in the early 1960s. According to the engineers who worked on the project, the SOHC 421 engines produced around 625 hp and were capable of turning 7,000 rpm.

One version of the engine featured camshafts driven off the front of the engine, another design had the cams driven by gears off the back of the engine.  Apparently at least one of these engines survives under the hood of an engineer’s personal Pontiac.

1967 Cadillac Eldorado V12

As part of the General Motors V-Future cars program, Cadillac developed an overhead cam V12 slated for production in the late 1960s. The V12 engine was to make its debut in the new FWD Eldorado in 1967.

Six prototypes engines were built in 1963 and 1964, all with a 60-degree architecture, chain driven overhead camshafts and hydraulic finger followers. The initial displacement was 7.4 L, but an 8.2 L was also tested. A number of different induction systems were tested, including a single four-barrel, dual four-barrel, and triple two-barrel carburetors, as well as mechanical fuel injection. Output ranged from 295 to 394 horsepower.

Based on the power output listed above you can see why the Cadillac V12 program was killed. Not only was horsepower disappointing, but GM was also concerned about the engine’s ability to meet upcoming mandated emissions controls. Another tragic tale of concept cars and engines not living up to the hype.

1969 Plymouth Weslake DOHC V8

It’s unknown whether this project was purely for racing, or Plymouth had the intent to offer the motor in a street car at some point. Keep in mind that the entire Chrysler group witnessed the excitement and positive impact on the brand when the previously race-only 426 Hemi was offered in production cars.

Following the 1968 season, Richard Petty announced he was leaving Chrysler and going to Ford for the 1969 NASCAR season. The money allocated for Petty was used to develop the Plymouth Indy DOHC V8. Design work began in February 1969 and running engines were provide to Andy Granatelli’s STP race team less than 90 days later.

The designer of the special cylinder heads was Harry Weslake, a British engineer best known for his expertise in gas flow through internal combustion engines. If you recognize the name, it may either be for his V12 engine in Dan Gurney’s 1967 Belgian GP winning Eagle, or the Gurney-Weslake cylinder heads used on GT40 Fords.

The engine lacked top-end horsepower necessary to compete and produce a potent enough top speed at the high speed oval tracks, it had plenty of bottom-end torque which made it quite competitive on the short oval. In fact, Art Pollard drove the Plymouth-Westlake engine to victory at the 200-mile Indy car race at Dover, Delaware on August 24, 1969. This would turn out to be the only victory for Plymouth in the history of Indy Car racing.

Bonus: 5 Of The Best 60s Muscle Car Motors!

So you’ve seen the biggest and some of the more obscure engine models out there, but which power plants were actually the greatest muscle car engines of the Swinging Sixties?

In only the last few year have engineers been able to leapfrog the performance of engines built 50 years ago, engines that have long since become legend, their presence in a restored muscle car not only bringing extra dollars on the auction block but plenty of oohs and aahs from onlookers poking their heads under the hood at auto shows and in car reviews.

There have been rumors over the years that these engines have been severally underrated for a variety of reasons. In reality, when freshly rebuilt versions using 100% stock components have been run on a dynamometer, their output is consistent with what the factory stated.

Recall that the engineers of the 1960s could predict airflow through CFD (computational fluid dynamics), deliver fuel via a direct injection system that pulsed the output to assure the best possible mixture, computers that consistently monitored all engine functions that allowed maximum performance under the available condition, or any of the other tools and gizmos available to engines today.

The most these pioneers of performance had at their disposal was a flow bench, a dyno, but mostly their own experience and skill, yet they still created some of the most memorable motors in the brief history of the automobile.

1965 Ford 427 FE Side Oiler

The famous side-oiler configuration of the FE (Ford-Edsel) block was developed for the Shelby Cobras as they moved up a class in international sports car racing. The engine was quickly adopted as the block of choice among all competitors because of the path of oil through the engine allowed it to rev above. 6500 rpm. Very few 427s made it into production cars and most of the those were intended for racing, particularly stock-based drag racing classes. Rated at 425 hp in Gross trim, output was consistent with its competitors. Ford even experimented with a SOHC version of the engine, but it was never installed in a production car. While the 427 designed as a race engine (and a very successful one winning the 24 Hours of Le Mans 24 fitted to the GT40 and the Daytona 500 with a Fairlane)  it was a little too finicky to be a street motor, so the 428 was created to meet that need.

1966 Chrysler 426 Hemi

Chrysler had been playing cat and mouse with NASCAR for a number of years regarding the legality of the Hemi engine, which had as of yet not actually been delivered to a paying customer in a passenger car. By 1966 Chrysler had no choice and offered the Hemi in a number of different models, and not just performance cars. There were several plain-jane Coronet four-door sedans ordered with the “eleplant motor.” Displacing 7.0 L (426 CID), the engines were both massive and expensive to build, so only 11,000 were installed in passenger cars between 1966 – 1971. The engine produced 425 hp in “gross” form and 350 hp in “net” trim.

1969 Chevrolet ZL-1

To bypass corporate rules that limited engine sizes, racers used the special-order (COPO) system to get the cars they wanted. When ordering COPO 9560  you received  a Camaro with an all-aluminum 427 CID ZL-1 big block.  Unfortunately for us, just 69 ZL-1 Chevrolet Camaros were produced, but not surprisingly as each engine was hand-built and  cost over $4,00, more than the cost of a base V-8 coupe. Though rated at 430 hp gross, the ZL-1 made 376 hp in its net configuration, not inconsistent with the output Chrysler was pulling from the Hemi.

1969 Ford Boss 429

Perhaps the best muscle car street engine of the era was the Ford Boss 429. Completely unrelated to either the 427 and 428, both which were based on the Ford FE block, the 429 was developed around the new 385 block (the name comes from its original crank stroke, not its displacement). It used four bolt mains, a forged steel crank and  rods, and aluminum cylinder heads, which had a modified Hemi type combustion chamber topped by a used a single Holley four barrel carburetor mounted on an aluminum intake manifold. The engine wouldn’t fit in a stock Mustangs so the body shells were shipped to a subcontractor to modify. Little wonder only 859 were made.

1969 Ford Boss 302

The Ford Boss 302 was built  for one purpose – to win the Trans-Am Championship against Camaro, Challenger, Barracuda, and Javelin. The  small block V8 motor was created by mating the heads from the yet-to-be-introduced Ford Cleveland V8 to the a 4 bolt heavy duty block of the Ford Windsor. The heads are “tunnel-port” where the pushrod runs a straight path through brass tunnel in the intake runner allowing for better airflow, a design adopted from the  427 FE. Atop a taller, higher manifold was fixed a four-barrel carb. In stock form it produced 290 HP in “net” trim, only 60 hp less than the Hemi that 30% larger.


About Chris Riley

I have been wrecking cars for as long as I've been driving them, but I keep coming back for more. Two wheels or four, I'm all in. I founded GearHeads.org and then built and ran AutoWise.com until selling it to Lola Digital Media in 2020. I look forward to watching AutoWise grow as part of the AllGear group.