The new Chevy Corvette ZR1X is pretty exciting for a lot of reasons. A twin-turbo hybrid powertrain delivering sub-two-second 0-60 times? Awesome! But the price… After taxes and titling, we’re looking at a quarter-million-dollar hypercar here. Forget a “working person’s” budget, there are wealthy heirs and heiresses who will see that price tag and settle on a C4, instead.
But at least you get a whole car for that price, right? You could be spending up to half a million bucks and walk away with an engine on a trailer that you have to wheel back to the garage and install yourself, like the Fuhrmann Engine, a flat-four hemi that powered legendary Porsches like the 550 Spyder and the 904 Carrera GTS to victory at Le Mans and the Carrera Panamericana. Some have called this the greatest engine ever made, and, truthfully, that’s hard to contest. Here’s what makes this powerplant such a treasure.
A Look At The Fuhrmann Engine
547 Porsche flat-four hemi engineBring a Trailer
The Fuhrmann Engine goes by the internal name of the Type 547. It’s also called simply the “Porsche flat-four hemi.”
Porsche Type 547/1 Engine Specs
Displacement
1,498 cc NA 4-Cylinder
Bore
3.3 Inches
Stroke
2.6 Inches
Power
110 hp @ 6,200 rpm
Torque
96 lb-ft @ 6,200 rpm
Compression Ratio
9.0:1
0-62 mph (550 Spyder)
10 Seconds
Just listing the numbers… that doesn’t really do this engine any justice. The engine, built in the early 1950s for Formula One racing, was developed by Ernst Fuhrmann, the honorary Vienna University of Technology professor who would eventually serve as chairman of the board at Porsche through the 1970s.
The engine was an air-cooled four-cylinder, and was set apart from similar Porsche engines at the time by its miniature ring-and-pinion gear sets, consisting of eight differentials, and a pair of overhead camshafts on both of its Volkswagen-style two-pot cylinder banks. Sounds complicated, right? That’s why you only see this engine packed into the most exotic of dream cars.
“High-Maintenance” Doesn’t Begin To Cover It
547 Porsche flat-four hemi engineBring a Trailer
The 547 has more in common with grandfather clocks and Rolex watches than it does with a typical flat-four engine. Just working on one of these things demands a ten-year apprenticeship, according to Bryan Lagas of Speedsport Tuning.
Porsche only made 1,703 of these engines from 1953 to 1964, produced mainly for professional racing, and occasionally finding their way into the hands of wealthy collectors and enthusiasts. The supply is dwindling, and original parts are hard to come by. As Lagas told Auto Evolution, “they still have some inventory, and sometimes we can convince them to reproduce a part, but that can take years.”
In other words, it’s not just the scarcity or the fact that you’re buying a piece of German automotive history. Buying a 547 is like hiring Frank Lloyd Wright to design your coffee table. In order to even touch one of these things, you need to take part in a decades-long lineage of engineering passed down from generation to generation.
According to Speedsport Tuning’s Jeff Adams, who studied under Porsche engines master Gerry McCarthy, cutting his teeth on 911s, the timing alone can be an excruciating process of trial and error. If the original etchings, Adams says that the job might take six hours, but without them, “you have a one-in-31 chance of getting it close enough to turn over without bending something. It’s not in the shop manual. My mentor never explained it. I had to figure it out the first time I replaced a gear set.”
Put it one way: if you’re thinking of grabbing one of these to while away the hours as a weekend project, you might as well build yourself a quantum harmonic oscillator while you’re at it, you know, just for fun.
Records And Wins With The 547
1958 Porsche 550 Spyder racingBonhams Cars Online
The Type 547’s first official win was in 1954, when a 547-equipped 550 Spyder was driven to class victory by Hans Hermann in the Carrera Panamericana race in Mexico. Hans Herrman also scored a class win and sixth overall at the 1954 Mille Miglia. Another 550 Spyder, driven by Umberto Maglioli, carried Porsche to its first overall victory at the Targa Florio in 1956, and the 1953 24 Hours of Le Mans legendary “double victory” was another 550 Spyder win.
Like many of Porsche’s finest engines, the 547 wasn’t the fastest or most powerful engine of its day, rather, it was simply a marvel of engineering, producing more power than you’d expect of a 1.5-liter flat-four.
What Exactly Will One Of These Engines Cost You?
547 Porsche flat-four hemi engineBring a Trailer
When we say that a 547 engine will cost you “more than a Corvette ZR1X,” that’s a conservative estimate, but we do have the market data to back it up. In late 2024, a Porsche Fuhrmann Engine sold on Bring a Trailer for a whopping $230,000. The engine had a single owner from the 1980s to the early 2020s, and another after a 2021 sale. Another Bring a Trailer listing for a 1955 engine closed at $220,000 in mid-2019. So the starting point for a complete engine is in the low $200,000 range.
Even An Incomplete Engine Costs An Arm And A Leg
547 Porsche flat-four hemi engineBring a Trailer
Bring a Trailer also has a listing for a Porsche Fuhrmann “engine project,” which sold in early 2025 for $128,000. Now, by “engine project” they mean that it’s not a complete, assembled engine, but basically a box of parts that they shipped to the winning bidder. And, as mentioned, building one of these things is beyond the abilities of even the most experienced at-home mechanics. To say it’s not a beginner-friendly project would be the understatement of the century. Without a ten-year apprenticeship, it’s just a box of bolts.
There was also an eBay listing, lost to time by now, for a 547 that was actually rebuilt and pickled in bean oil for more than 12 years. Pickling is a method more common with boat engines, intended to keep the motor free from moisture and corrosion in the off-season, typically for a year at a time, maybe two years at most. Soaking an engine in oil does help to keep it in ship shape when it’s not in use, but it’s not ideal for long-term storage.
547 Porsche flat-four hemi engineBring a Trailer
A professionally rebuilt Fuhrmann Engine, like the ones they put together at Speedsport Tuning, can easily rack up a $425,000 bill. The question of whether or not the engine is actually worth the asking price, well, we’re talking about a piece of art, here. Ultimately, it’s worth what you’re willing to pay for it. If the Jay Lenos and Jerry Seinfelds and Mr Beans of the world think this engine is worth a bare minimum of $200,000, then that’s what it’s worth.
Would we pay a quarter million bucks for a Fuhrmann Engine of our own? How about this: you buy one and let us borrow it. We’ll put you on the front page of the website and everything. A complete 550 Spyder can cost millions of dollars. A 1958 model sold on Bonhams back in 2018 for $5,170,000, which is enough to buy you a small mansion in the Hollywood hills, so it’s no wonder people are paying six figures for 547s that are totally disassembled or soaking in bean juice.
Sources: Porsche, Bring a Trailer, Auto Evolution.
