The Ten Craziest Engines You Can't Buy Today

Crazy? I'll show you crazy!
Crazy? I'll show you crazy!

Wednesday, over on Jalopnik, they ran an article about the Five Craziest Engines You Can Buy Today.  We liked it, and we liked it quite a lot, actually. Nevertheless, we can’t help but think there’s a slight flaw in their logic — besides the huge, glaring omission of the Volkswagen Group’s series of W-engines, of course. Many of these engines are very nice, it’s true; but they’re hardly what we of the Hooniverse would call “crazy”. Most of them are pretty tame, if you ask us. So while we think Jalopnik did a great job on their selection of engines you can buy today, the entire Hooniversal Brain Trust sat down last night and discussed this. Let’s have a look at what “crazy” really is.
10. The British Racing Motors H-16 Suggested by Tomsk
The BRM H16.
The BRM H16.

In concept, the H-16 makes perfect sense. It’s essentially a pair of flat-eight engines connected to a common drive gear. As such, it gives you all the benefits of a large, powerful 16-cylinder engine with the cost-savings of being able to use parts from a common V8 engine. Unfortunately, in the case of the BRM H16, classic British attention to detail appears to have been its downfall. The designers claim that their engine specifications were never followed correctly, and as a result the castings ended up far thicker than they needed to be. As a result, the engine was a huge, appallingly heavy thing that the legendary Jackie Stewart described as being “better used as a ship’s anchor than as a power plant”.
9. Rootes TS3 “Commer Knocker” Suggested by Han_Solex
The Rootes TS3.
The Rootes TS3.

See if you can follow me here. The Rootes TS3 is a high-speed, two-stroke, three-cylinder, six-piston diesel engine. Wait, what? Yeah, that’s right. I expect I’ve made my case right there, but let’s continue on. It uses two horizontally opposed pistons to generate compression and ignition in each cylinder. The cylinders are on rockers, like a standard pushrod engine uses for their valves, but much, much bigger. The rockers then connect to the crankshaft. You know what, just go here. They explain it better than I can. The 3.5L engine produced a respectable 135hp and 335 lb-ft of torque. Those are respectable numbers… but hardly groundbreaking, so the engine is stuck here at position nine.
8. Cizeta V16T Suggested by Graverobber
Hey look, the actual engine! Thanks Braff, and Ray, and mom, and the Academy, and all the little people...
Hey look, the actual engine! Thanks Braff, and Ray, and mom, and the Academy, and all the little people…

I spent forever looking for a photo of this engine. Some guys named Ray Wert and Jeff Glucker found photos in like a minute. That’s a little irritating, but it should indicate just how rare these cars are. In fact, they’re quite the amazing vehicles, with a ton of trivia — but we’re only interested in the engine for now. Now, the name V16T is meant to imply a V16 engine, Transversely mounted. In fairness, however, it is not. In fact, in the interests of accuracy, it is two 90° V8 engines, mounted back-to-back and driving a central gearbox. Read that again. A central gearbox, with a V8 on either side of it, all in a common block. So it’s not two separate V8s, it is one engine, comprised of two V8s. Jeebus, my head hurts just trying to understand it. I need pictures. However, for all its mind-blowing awesomeness, it produced performance that was still around the same as any other supercar. If the only other car with specs that rival yours is the Veyron, in fairness, you should be able to run with the Veyron. It can’t, so it’s stuck down here at number eight.
7. JRL Choppers’ Rotec R2800 Suggested by Graverobber
The Rotec R2800. Think of it as 3½ V-twins. Kind of.
The Rotec R2800. Think of it as 3½ V-twins. Kind of.

The engine, by itself, isn’t all that amazing. It’s admirable, to be sure; it’s a very small Rotary engine intended as a replacement for the (generally quite poor) gasoline engines that are usually found in small two- and four-seat aircraft. JRL Choppers decided to take one and put it in a motorcycle. For sheer inappropriateness balanced against mind-blowing awesome, it gets the number seven spot, even if, strictly speaking, it probably doesn’t belong here. Let’s face it, we’re hoons, we like anything that’s a little bit batshit insane.
6. GMC Twin-Six Suggested by Mad_Science
The 702cid GMC Twin-Six.
The 702cid GMC Twin-Six.

Due to its nickname, the “Twin-Six” is often mistaken as being two commercial GMC V6 engines somehow welded together. And in fairness, at a casual glance, it sure as hell looks like it. In the interests of interchangeability, it uses two V6 exhaust manifolds for each cylinder bank, and two V6 valve-covers, two distributors, and so on. Many of the parts for this massive 702-cid V12 were interchangeable along the entire line of GMC’s V6 engines, which kept not only production costs but costs of ownership remarkably low. For that huge level of consideration, and its resulting cool, we’re bumping this engine — which is largely just a big production truck engine — all the way up to  position six.
5. Anything Used by Blastolene Suggested by Braff, indirectly.
Blastolene says, "It'll fit."
Blastolene says, "It'll fit."

Braff suggested a few different engines, such as the Lincoln Flathead V12 or the pre-war Cadillac V16 engines; any one of these really does deserve to be on the list just for the sheer number of cylinders; the problem is, however, they just weren’t that awesome. Low horsepower ratings, poor reliability, and heavy weights served as limiting factors until they were heavily re-worked by the aftermarket. It’s only today, with our newer technologies, that some hot-rodders are managing to accomplish some really wild things with them. Does that make them awesome? Well… in the hands of a company like Blastolene, yes. Just go look at what they do. They’re building hot-rods around tank engines, aircraft engines, old Peterbilt engines… frankly, I wouldn’t be surprised to see a diesel engine from an old naval destroyer showing up in a future rod. Batshit insanity, and the usage of engines wholly inappropriate for road-going vehicles gets them an automatic spot at number five.
4. Bugatti U16 Suggested by Deartháir
The King-Bugatti U16.
The King-Bugatti U16.

Similar in concept to the H16 engine above, instead of using two flat-eights mounted horizontally, the Bugatti engine uses two straight-eights mounted side-by-side and vertically, all in a common block. When this engine came out, the straight-eight was seen as the epitome of power, style and all-around awesomeness. Bugatti capitalized on this hype by using two of them! Simple, effective, elegant, and over-the-top insane, just as all proper Bugattis always have been. Unfortunately for us, this engine, a 24L behemoth, never really found a proper application. It was attempted as a tank motor, an aircraft motor, and after WWI, as a concept-car motor. It was even attempted briefly as a “quadremoteur” version, which featured a 48L displacement and four banks of straight-eight engines. But it never went anywhere, and never really got used for anything other than a few conceptual tests, so while it would be fighting for the number one spot, it’s relegated down here to number four.
3. Ford 427 SOHC “Cammer” Suggested by Mad_Science
The "Cammer".
The "Cammer".

Wait, what? What’s so crazy about this? It’s just a big V8! Well, yes, but we’re granting a bit of leeway here; it’s not the engine itself, it’s the mentality that went into developing it. Essentially, Ford just wasn’t quite doing as well as they would have liked in some obscure racing series called “NasCar”. I know, I’ve never heard of it either, but apparently it was popular back in the 1960s. It seems people thought it was fun to drive in circles around a banked track; presumably you go as fast as you can until you get dizzy and vomit, and the last person to vomit wins. Sounds like fun! Regardless, it was terribly popular back then, and it gets a nod from us because of the Ford engineers’ mentality when designing it. They started with the best engine they had, the FE 427 side-oiler, and set to work improving it however they could. They looked at every high-performance engine available, whether it was from Chrysler or Ferrari, and adapted its best piece of technology to be added to the Cammer. Single overhead cams, exotic high-temperature valves, factory porting and polishing, hemispherical combustion chambers, tunnelport high-rise intakes, and a complex series of idler pullies to idealize the valve timing; all the tricks your average backyard mechanic would use to get more power out of an engine were already employed at the factory. In addition, Ford told the Cammer owners tricks they had learned of how to get more power. The engines were conservatively rated at around 650 horsepower from the factory; as each engine was hand-built, that was considered to be the “minimum” rating. Most had significantly more. Yeah, it’s just a big V8, but it’s kinda awesome.
2. The Rolls-Royce Merlin Suggested by Deartháir
The legendary Merlin. All. Hail. Merlin.
The legendary Merlin. All. Hail. Merlin.

Let’s face it, the Merlin is one of the greatest engines of the 20th Century, and anyone who says differently is clearly a terrorist and hates freedom and love and puppy dogs and all that is awesome. It’s been used for absolutely everything; marine, aircraft, tank, commercial truck and hot-rod applications. Didn’t know that? Sure. The Merlin engine was actually only the original, supercharged V12 engine, but it was used in many different forms under many different names. Simply removing the superchargers, or changing the crank, or swapping out the heads, or using different pistons, each resulted in a different name designation, but for all intents and purposes, it was still the original Merlin engine. Merlin was intended to be one in a rather large series of engines from Rolls-Royce, ranging in displacements from about 10L all the way up to almost 50L. As it turned out, the Merlin hit that sweet-spot between all of them, with the small footprint they needed for the smaller engines and the high horsepower they needed from the larger engines. It is versatile, powerful, and (for an aircraft engine) relatively lightweight. It’s little wonder that for over 60 years, when thinking of an over-the-top engine for an automotive project, the Merlin is one of the first ideas that comes to mind. Got a favourite Merlin-powered hot-rod? Post it in the comments, let us all drool about it. Let’s face it, if it weren’t for the engine that trumps it, this would rightfully be the number one engine. At 27L displacement and anywhere from 1300 to 3000 horsepower, it’s a hard engine to beat.
1. The Chrysler A57 Multibank Suggested by Murilee the Saucy Minx
Sweet Leaping Jeebus, it's the Multibank.
Sweet Leaping Jeebus, it's the Multibank.

Yes, the Merlin is a hard engine to beat, but if anyone is going to do it, it’s gotta be this one. Five banks. Thirty cylinders. 1,005-cid displacement. Constructed out of five of the Plymouth flathead sixes, it was designed to be adaptable and durable, and available in the shortest time possible. Simply put, America was going to war (finally), and they needed engines to power their Sherman tanks. Chrysler’s solution was simple to create, used existing parts, maximized flexibility, shifted paradigms, and utilized dynamic synergies. I have no idea what most of that means, but I’ve been talking to Braff again. Chrysler claimed that the Multibank would still be able to power the Sherman even if two full banks out of the five were disabled and not functioning. Good to know that even back then, Chrysler was planning their products around poor reliability. Oooooooh. Let’s face it, this is pretty frickin’ awesome. Go check Murilee’s article over on Jalopnik for some video deliciousness.
So, dear readers, what did we miss? What horrendous errors have we made? Fire away in the comments, maybe we can do a followup post. Or, someone else can, that was a lot of bloody work.

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  1. joshuman Avatar

    The image search results for "destroyer engine" are not what I was expecting. There is a lot more Star Wars than Arleigh Burke. I did eventually find the USS Slater, a Cannon-class destroyer escort that served in the mid to late 1940s in the United States Navy. There are a number of photos of its V16 diesel available here:… A compact unit it is not.

  2. JeepyJayhawk Avatar

    The 427 Cammer makes me um… unable to go to lunch.

  3. PowerTryp Avatar

    Holy damn you have no idea how bad I want one of those 427 "Cammer" engine. Nothing screams awesome like a 7 foot timing chain.

    1. Smells_Homeless Avatar

      Actually, you can get a new 427 SOHC. The aftermarket makes every piece necessary. I can't find any crate versions though, so you're going to have to track it all down.

      1. PowerTryp Avatar

        So I've noticed while doing research here again. I'm getting that excited feeling lower down.

      2. Tim Odell Avatar
        Tim Odell

        You might want to talk to these guys:

    2. Jerome Avatar

      Why a Chevy engine didn't make the list ?

      1. Brian Borell Avatar
        Brian Borell

        Because all Chevy engines are as common as bellybuttons. Booorrring!

  4. discontinuuity Avatar

    One thing about that Rolls-Royce: airplanes got 70 hp and 10 mph just by angling the exhaust ports backwards, because the exhaust gasses were exiting at 1,300 mph.

    1. Han_Solex Avatar

      I love this fact with every fiber of my being. That is awesome.

    2. Boo Avatar

      Rolls-Royce made aeroplane engines not airplane engines.

  5. engineerd Avatar

    Oooohhh…the Merlin. Only to be followed by the most insane engine of all time. My favorite Merlin-powered hot rod was the Supermarine Spitfire. Oh, you meant cars. Well, how about some useless knowledge about the Merlin? The first prototype Merlins were designed to use evaporative cooling. What's this you ask? Generally, in a water cooled system you don't want the heat transfer fluid to boil. However, there was a thought that if you let the fluid boil it could remove even more heat and become superheated. Unfortunately, this meant you needed condensers in place of the radiators on a traditional water-cooled arrangement, and the the condensers needed to be much larger than the radiators. On high speed aircraft, this adds a lot of drag so it was abandoned.
    For crazy engine you can't get today, I would say the ZAZ air-cooled V-4 engine used in the Zaporozhets. For nothing else than it is the antithesis of the Merlin.

    1. Standpipe Avatar

      The Napier Sabre engine beats it hands down on complication, ingenuity, and power. It's an H 24, ie two flat 12 motors one on top of the other, sleeve valves, gear drive to the propellor, two stage super charging. A far mor advanced motor than the Merlin, with a reputation for unreliability, but LOTS more power

      1. HarryMann Avatar

        Ultimately Napier Sabres became nicely reliable and powered two awesome aircraft.
        It was the first aero-engine to achieve 100 hour certification at 2,000 HP going on to produce up to 5000 HP on the test bench it’s said and 3000 in service.
        The Hawker Typhoon featuring as a cannon and rocket ground attack aircraft becoming feared by German armoured battalions during and after D-Day was the first to use it in service.
        Subsequently the Hawker Tempest (a thinner winged development of the Typhoon and forerunber of the ultimate Sea Fury) became a superb all round air superiority fighter, feared even by ME 262 jet pilots for its awesome acceleration.
        14’6″ propellors were required to absorb thus sort if power making it a bit if a handful on take off.
        The Sabre was about 37 litres and revved higher than any contemporary aero engine (circa 4000 rpm). Its Power/weight ratio and compactness were remarkable.
        No Sabre runs today unfortunately… but it should definitely be at the top of this list.. a sleeve-valve stunnee.. designer by Sir Frank Halford, a good mate of Sir Frank Whittle and Harry Ricardo (IC engine wizard)

    2. Harrymann Avatar

      It wasn’t drag that was the problem with evaporative cooling. In fact that’s why it was used in the first place.. to reduce drag. It was the high surface area required, the complexity of pipework and making it efficient enough… after all when a normal system overheats it boils over but an evap system is already effectively boiling 🙂
      and of course it wasn’t the Spitfire either that Mitchell tried it on… it was the Schneider Trophy winning seaplane racers back in the mid 30’s.

    3. zardoz337 Avatar

      I love me some merlin, always have, always will The mere sound of a merlin firing up is enough to set my heart racing. To be completely honest though as much as I love the merlin, I am FANATICAL about the merlin’s successor, the griffon. As much as the merlin spitfire was a hotrod (and actually saved the P51 from the scrapheap) the Griffon Spit was a full on rocketship. The vaunted MKXIV starts out with a savage growl that intensives to the wail of 10,000 screaming banshees that will cause any gearhead to freeze in place and stare in wide wonder. The Rolls-Royce Griffon, in some variants, doubled the power output of the mighty merlin. ‘Nuff’ said.

    4. Boo Avatar

      The ZAZ is very much like a VW Beetle engine, but bent into a 60 degree V.

    5. Jim Young Avatar
      Jim Young

      Actually, some Unlimited Air Racers do use boil off systems for the oil coolers, allowing more efficient engine coolant radiators, lower profiles, with relocated cooling system components. In a few cases mentioned at the link, boil off systems were used for both for oil and engine coolant). See

  6. BGW, Capt (Ret.) Avatar

    <img src="; width=500 height=333>
    Life W12. Perhaps the worst F1 engine ever produced, but what it lacked in power, torque and reliability, it made up for in fuel savings due to never actually making it out of pre-qualifying crazitude.

    1. PowerTryp Avatar

      Any body got a spare titanic laying around?

    2. Deartháir Avatar

      I'm thinkin' a rat-rod with straight-pipe exhausts.

    3. Tanshanomi Avatar

      Get rid of the little moped engine Jesse James put in his trike.
      <img src=""&gt;

    4. Impalamino Avatar

      "Hey man, check out my new chrome valve covers! Pretty sweet, right?"
      "Not bad."
      "What are you running?"

      1. FЯeeMan Avatar

        I lol'd. Thanks.
        I was thinking you could move large apartment buildings with that.

        1. Red Five Avatar
          Red Five

          Or small planets.

    5. towie Avatar

      Imagine how many rattle-cans of HTP that would take.

  7. Tanshanomi Avatar

    I feel obligated to bring up the Evinrude 300 V8 2-stroke (220 HP rear wheel HP). I know I've posted this video over at The Redacted Blog at least twice, but man-oh-man, does this one ever get my combustion chamber all oily…
    [youtube lRKeuHyI0lw youtube]

    1. Alff Avatar

      To say nothing of the effect it has on my lower unit.

    2. J.C. Avatar

      Anybody want one? Here's one for sale….

      1. Tanshanomi Avatar


    3. CptSevere Avatar

      The sound of that screaming banshee sent cold chills up my spine. WANT.

    4. FЯeeMan Avatar

      What was up with the dyno read out? The numbers looked like they were all over the place. The graph looked like an Etch-a-sketch with a spastic 2 year old at the controls.

  8. Alff Avatar

    Jalop just linked this, referring to Hooniverse as a "Jalopnik fan site". I think y'all need to return the favor.

  9. aaronx Avatar

    More Merlin Trivia:
    It should probably re referenced as a Rolls-Royce/Packard Merlin. Rolls-Royce didn’t have the manufacturing capacity to build as many Merlins as the RAF wanted, so they asked Packard if they could build some. Packard re-designed the Merlin to allow for mass production (‘FTFY’ as it were), something that freaked out the Roller folks at first. When they finally got some of the Packard Merlins into the shop, they found them to be superior to the hand-built ones and apologized (and switched their own tooling to Packard’s design).
    You can still get parts for them pretty easily, thanks to air racing and ‘classic’ powerboat freaks.

    1. HarryMann Avatar

      Pretty well all of that is total rubbish!
      RR were already producing over 4,000/annum before the British Govt. gave Packard the contract.
      They didn’t re-design the Merlin, they re-drew the 2500 drawings to US standards (3rd angle projection).
      Changed some of the ancillaries such as carb and magneto and pumps to suit local US supplies. Some of the thread forms were adapted and Packard used an epicyclic drive for the supercharger in place of the Farman drive.
      All engines were hand built there were no robots on those days…
      And RR did not change their production methods other than consistent improvements throughout the war as would be expected.
      Packard did find time to do some development work and occasionally changes would be incorporated at RR plants here. Likewise RR engineers were ever present at Detroit feeding back updates mods and engineering know how from Derby.
      The first major batch received in the UK were all rebuilt at the RR Glasgow facility…due to faulty bottom ends. Glasgow Hillington itself a major plant built from scratch in 1940 to mass produce Merlins and rebuild in-service engines.
      There was no appreciable performance ir reliability differences between British and US built Merlins.
      I suggest you read the book…
      “Hives and the Merlin”

      1. JFowler Avatar

        Interesting point of view you have there. Might I suggest that reading a few books on the topic you expound upon would leave you more informed. Perhaps some of the wonderful books published by the Rolls Royce Heritage Trust. Derby was not allowed to try every change they wanted – the British government needed a solid supply of Known-Good engines – so Derby had many larger changes put into production in Detroit.

  10. Tanshanomi Avatar

    Sing along!
    "Break me off a piece of that Merlin mill…"
    <img src=""&gt;

    1. rennsport964 Avatar

      And look, it's got NAAAAAAWWSS.
      God help you if you get your pantsleg caught on the chains. Thwapthwapthwap!

    2. joshuman Avatar

      I had to look really hard to find the foot peg and then I recoiled in terror at the swing arm construction.

      1. Tanshanomi Avatar

        Not to mention those spindly fork tubes. They look to be late GS850/1100G forks, which would be all of 37 mm in diameter. Egads!

  11. P161911 Avatar

    I'd like to add the Allison V3420 an X-24! engine to the list. Two Allison V-12s run on a common crank case for 2100HP from 3,421 cubic inches!

  12. P161911 Avatar

    I had to do a little research on the BRM H-16. A few years before they built the H-16 they built a 1.5 liter V-16, yes a 1500cc V-16. I remember this from Nick Mason's book At the Limit. It was the only car out of all his cars reviewed for the book that they couldn't get to run long enough to do the tests.

    1. Matt Dupuy Avatar
      Matt Dupuy

      It was a SUPERCHARGED 1.5 litre V16, no less. It allegedly generated 600hp at full chat, although it was rarely running for long enough for anyone to test.
      For other engines, how about the Lotus 59, which was powered by a Pratt & Whitney gas turbine and nearly won the Indy 500. And if that isn't road vehicle enough, how about this?:

  13. Racin_G73 Avatar

    The NASCAR-hate is strong in this one!

  14. scroggzilla Avatar

    WHAT?!?! NO NOVI V8?!?!?!

    1. Deartháir Avatar

      Tell me more…

      1. scroggzilla Avatar

        Used extensively at the Indianapolis 500 for 3 decades, designed by Bud Winfiled and Leo Goosen and built by Offenhauser. First introduced for the 1941 Indy 500, the Novi was a quad cam V8 displacing 3.0 liters (to my knowledge the Novi was one of the 1st quad cam V8's) With it's trademark Paxton centrifugal supercharger (producing 30 psi of boost) and a triple carb set up, the original Novi cranked out 450 hp at 8000 rpms. Over the next 3 decades, the engine was continually developed earning a celebrity reputation with fans for it's unique engine note while simultaneously earning a widowmaker/car breaker reputation with drivers. Power delivery was unpredictible, with a surge of power coming on suddenly at high rpms….not a good characteristic at a track like Indy. The engine was so powerful and highly stressed that it frequently broke itself (usually connecting rods or pistons) or the car around it (driveshafts, differentials and tires). These factors lead to many crashes over the years with 2 fatalities.

        1. scroggzilla Avatar

          The final incarnation of the Novi appeared at Indy in 1966, in a 4wd rear engined chassis developed by Ferguson and Andy Granatelli and driven by Bobby Unser. That version of the Novi displaced 2.7 liters and, with a 2 stage Paxton supercharger, produced a whopping 837hp at 8200 rpms. While the car showed promise, being far more stable than it's FWD or RWD Novi powered predecessors, it crashed in practice. While the Novi never won at Indy, it did set speed records at Bonneville and at Monza during the Race of Two Worlds. Karl Ludvigsen wrote the definative tome of Novi powered race cars and, as with anything he writes, it's worth a read.

  15. […] Wednesday, over on Jalopnik, they ran an article about the Five Craziest Engines You Can Buy Today.  We liked it, and we liked it quite a lot, actually. Nevertheless, we can’t help but think there’s a slight flaw in their logic — besides the huge, glaring omission of the Volkswagen Group’s series of W-engines, of course. Many of these engines are very nice, it’s true; but they’re hardly what we of the Hooniverse would call “crazy”. Most of them are pretty tame, if you ask us. So while we think Jalopnik did a great job on their selection of engines you can buy today, the entire Hooniversal Brain Trust sat down last night and discussed this. Let’s have a look at what “crazy” really is …  Details […]

  16. mike h Avatar
    mike h

    enjoyed browsing through the coloum great photo,s mikemike h

    1. Kim Armand Nielsen Avatar
      Kim Armand Nielsen

      Anyhow, that one was a major flop for Honda: Intended to be the revival of fourstroke engines in roadracing Honda didn’t manage to get the weight of the 500cc down in competetive scale, even several expensive inventions was added (ex. The carbón fibre outer-Shell monocoque frame). In endurance did the engine as a 750cc have hard time compleating races and after the first and only victory it was withdrawn by Honda, seemingly long awaiting any positive experience to follow the concept into the grave.
      Even as a limited edition street-legal 750cc had the productionto be cancelled at only half of the planned numbers (IIRC: planned to be 500 pcs built yearly in only 3 years)!
      But the tech is amazing stuff to see!

  17. P Smith Avatar
    P Smith

    Where’s Mazda’s quad-rotary from the 797B that won at Le Mans in 1991? The FIA banned rotary engines for 15 years because of it, to allow piston engines to catch up in reliability. They never did catch up.
    And why the hell won’t Mazda allow the public to by the RX-8 with the triple rotary engine, at 450bhp? The Porsche 911 can’t keep up with it.

  18. zuma Avatar

    Ford built a huge aluminium V8 that was fitted into tanks designated GAA. It's pretty impressive.

  19. Connie Leibe Avatar

    Wow, gives thanks a bunch m8

  20. louis vuitton Avatar

    Greetings, I enjoy your blog. This is a great site and I wanted to post a comment to let you know, great job! Thanks Louis
    Louis Vuitton

  21. Rob Avatar

    Napier Nomad for extreme complexity and taking supercharging to its logical conclusion…

  22. […] since I did an article last year about the Ten Craziest Old Engines over on Hooniverse, this particular one has stuck in my head. It’s called the “Commer […]

  23. chris harris Avatar
    chris harris

    There are two great engines that you've missed. The first is the Napier Deltic diesel engine. In vertical section, the engine forms an inverted equal sided triangle. The three crankshafts are located at the corners and the engine is an opposed piston design. The engine was supercharged, most castings were aluminium and the world had seen nothing like it! Output was prodigious. It powered various types or large, high speed boats (for which it was originally designed) and Britains high speed main line deisel electric locomotives in the 1960's to 1970's. The second engine worth mentioning was also a Napier design this being the Napier Sabre aircraft engine. Designed in the early 1940's the Sabre was an alternative to Rolls Royce Merlin and later Griffon engines. Due to its mechanical complication, it was initially unreliable but improved over time: it was far an away the most powerful piston aero engine of its day with around 4000hp when fully developed but required rebuilding after approx. 85hrs flying. It was a sleeve valve design and the cylinders were H layout. A magnificent effort by Napier design engineers. Anyone wanting truly serious horsepower would need one of these…….if you can find one.

    1. RWM Avatar

      That is ridiculously unfair lol, I read all the way to the bottom marvelling that no-one had put a Deltic in the list and feeling very proud of what I was about to post.
      The really beautiful thing about deltics is that with one crankshaft rotating the opposite direction to the other two they self-cancel all the primary out of balance forces in the dynamic part of the system, thus removing the need for crankshaft counterweights and reducing weight and internal inertia. The Deltic Rail Fleet that ran on the East Coast Mainline was 'guaranteed' for a fleet mileage of 4.5 million miles per year for their first 5 years of existence, as long as none of the 22 locomotives exceeded 220000miles a year individually, at the time they were truly revolutionary, and at around 100 tons for 3300 hp were a considerable advance on the class 40 1-Co-Co-1 s which had about 2000hp in a 130+ to unit.
      The engines need to be scavenge blown (forced induction) since they don't have any proper induction stroke per se, and some variants were turbo-charged, including the 9-cylinder version used in the EE type 2 'bably deltic' locomotive. The 9 cylinder deltic Engines were used mainly as auxiliary power units on naval ships, I believe that some of these units are still in use, but I'm not sure so if someone can back that up it would be great.
      There was a prototype variant of the 18 cylinder deltic with a gas turbine down the middle of the three banks running off unburnt fuel in the exhaust…according to wiki, this prototype produced 5600bhp on test before throwing a rod.
      I noticed that the article also links to something caled a Zvezda M503 which apparently was the equivilent powerboat engine from the other side of the cold war…nowhere near as elegant, or as nuts but worth a look all the same.

      1. RWM Avatar

        sorry, I didn't spot koivis' link to the Zvezda

    2. Kim Armand Nielsen Avatar
      Kim Armand Nielsen

      The Deltic wasn’t supercharged, but like any other two-stroke engine without scavenging cranckshaft-housing, it had a blower to secure the scavenging of fresh air when the inlet-port was exposed.
      Anyhow, it’s an amazing engine and one of My favourites. Actually it is developed out of a German flat six aviation Diesel engine 😮

    3. Kim Armand Nielsen Avatar
      Kim Armand Nielsen

      I’ve heard the Merlin-engine to have a span of IIRC only 48 hours between major overhauling – But since that exceeded the average lifetime of a pilot it wasn’t a major problem.
      The Sabre would fit in under same ‘rule’ and rebuilding wouldn’t actual be done in many situations :-/

  24. John Grady Cole Avatar
    John Grady Cole

    What no mention of Harry Miller's Blown four cam V16s from 1931? 1100 cubic inches turning 6,000 rpm and making 1800 horse power. Two of them (total production) were commissioned by Gar Woods for his record attempt mahogany racer.
    hear one started….

  25. gary Avatar

    hope you guys discover the napier delta engine 18 cyl 2 cranks

    1. Kim Armand Nielsen Avatar
      Kim Armand Nielsen

      3 cranks! And 36 pistons 😮

  26. Oren Avatar

    I think I remember a design from Bill Lear: Delta configuration formed by three cylinders, three cranks (one at each apex of the delta, each crank connected to two pistons), and six pistons, two in each of the sides of the delta. Ignition at the center of a cylinder, pushing outward on the two pistons and driving two cranks. Can anybody confirm?

    1. Ozz Avatar

      It was called a Napier Deltic.
      The "Deltic" Engine was developed in the 1940s by Napier & Sons of Manchester, England to address the needs for high speed naval vehicles. The resultant engine had an excellent power-to-weight ratio, was compact by marine standards and was used in a variety of marine vessels. Two units were fitted in the famous "Deltic" type V locomotives (later class 55) used on Britain's railways between 1961 and 1981.
      Absolutly mental 2 stroke diesel engine

      1. Kim Armand Nielsen Avatar
        Kim Armand Nielsen

        As a stolen German design it’s post-war!

    2. jeremy fine Avatar
      jeremy fine

      Sounds like a Deltic diesel as used in the English Bush Locomotives of the 60's

  27. Steve Avatar

    For sheer mechanical lunacy, the rotary radial (stationary crankshaft, engine rotates) aircraft engines of World War I have to be the champions. The Zvezda's craziness credentials are much improved if you know that it started out as an intended aircraft engine, for Tupolev's B-36 equivalent.

  28. bigbill Avatar

    good old detroit 71 series 2 stroke diesels

  29. Randy Avatar

    you forgot all the big one cylinder engines like the hot bulb and hit and miss. here is an example in application

  30. jez Avatar

    laid hands on the Napier Nomad at the Smithsonian. one of two in existence. pretty exclusive cannot buy at any price hardware. bit of corrosion here and there but diesel power and an axial supercharger. Best of everything.

  31. Chippy Avatar

    How come you haven't included the Napier Deltic engine?

  32. Transexl Avatar

    As they are no longer built, barrel/wobble/swash plate engines do count, right?
    A quick search brought up this :

  33. Ruvy Avatar

    What about the Lancia TriFlux enigine

    1. cap'n fast Avatar
      cap'n fast


  34. cap'n fast Avatar
    cap'n fast

    I just saw tow of the strangest engines. the maritime world is full of strange things. they made engines very compact when designing for submarines. case in point: the agss albacore. diesel/electric research sub. main engines made by GM.16 cylinders per cyl in and X configuration, vertical crankshaft with the generator mounted below it. about 1000hp per engine(x2) main use is to recharge the batteries. main propulsion is two 7500 hp concentric dc motors driving counter rotating propellers.what a machine!
    you can lay hands and eyes on this beastie in Portsmouth NH, that's a real hybrid drive.

  35. D Davies Avatar
    D Davies

    Being English, I'm quite proud that a lot of interesting engines were designed & manufactured in the UK, some of which feature here; however, presuming this is a mainly US site, I'm surprised nobody has mentioned the Nordberg radial 2-stroke diesels. Also there were a number of other US makers of radial diesels for aircraft, tanks & submarines.
    I worked for Foden's in the 60s when they were making a 12 cyl. 2-stroke turbocharged diesel: 9.6 litres, 440 bhp @ 2200 rpm & 1200 lbf-ft torque @ about 1300 rpm. It was for boats, & was two 6-cyl. lorry (truck) engines on a common crankcase with contra-rotating crankshafts geared to an output shaft – I suppose you would call it a U12 engine.
    Apparently Napier designed a square version of the Deltic, with rows of 4 cylinders. Also Rootes made a 4-cyl. version of the TS3, developing 200 bhp, but it was axed by the new owners, Chrysler, after only 14 were made.

  36. John Avatar

    You can still buy a 427 SOHC engine. I know, we make them.

  37. V24 Asti Spumante Avatar
    V24 Asti Spumante

    How could you miss the V24 Allison V3420? It makes some pretty hefty HP, Is very cool looking and rare, only 150 were made. I'd love to see a V24 in a car of some type.

  38. KingofGnar Avatar

    The Blastolene Peterbilt truck has a Detroit Diesel V12. They were manufactured by GM, not Peterbilt. A lot of non-GM trucks were equipped with Detroit diesel engines from the factory.

  39. Allan Avatar

    How about the General Motors 4-51 valveless two cycle diesel. Not much power (87hp) but very light and the absolute best engine for making diesel fuel into noise because you couldn't put a muffler on them. Built from 1951-59. It made the Detroit 12V71's sound quiet. I've got one in a 1957 Adams 220 road grader and I bought a used marine 4-51 for parts. Not many of the original 9800 built that are still running. Anybody got any parts kicking around? Very unique as the exhaust manifold bolts to the block directly above the supercharger and the camshaft only operates the injectors as there are no valves. Ten intake ports and three exhaust ports in each dry sleeve.

  40. Jim Avatar

    Pratt and Whitney 70 liter R-4360 Wasp Major Radial Piston Engine that was used in the B-36 bomber.
    As a kid growing up in the 1950's I used to hear the drumming hum of this engine long before it passed overhead at 30k feet. Awesome

  41. joshua Avatar

    480hp twincharged (super and turbo) 1.4L 1982 Lancia Delta S4 engine

  42. Joshua Black Avatar
    Joshua Black

    I’m just going to throw a few engines out there and let you all research them. Guaranteed to make your nether region tingle. Ford gaa and gac, Detroit diesel 12v-71 and 24v-71, fiat giant i4 (26litre I think), and the christler turbine

  43. Jim Caiella Avatar
    Jim Caiella

    About #7: rotary or radial? I’d love to see the yahoo with the rotary on a bike try and ride it.

    1. Kim Armand Nielsen Avatar
      Kim Armand Nielsen

      Isn’t the rotary the othervise called Wankel -engines?
      The radial-engine have been put into some bikes by costum-builders – In transverse as well as longitudinal position 😮

      1. Jim Caiella Avatar
        Jim Caiella

        Kim: Yes, the Wankel is a rotary and I know that both Wankels and radials have been put into bikes. But not traditional rotaries. #7 was called a rotary. It is not. It is a radial. Do not confuse radial and rotary, they are entirely different animals. The difference between rotaries and radials is that in the rotary, the crankcase, cylinders, induction and exhaust systems, and valves and actuators (among other pieces) all rotate about a fixed, non-rotating crankshaft. Virtually everything rotates. Hence you can understand my comment about putting one of those things on a bike. The torque is phenomenal. Not to mention having all that stuff spinning around between your legs. You’ve heard of the Sopwith Camel? And how dangerous it was for neophyte flyers? This is because of the massive torque of the plane’s rotary engine with the fully on-fully off throttles of the time (no shades of gray with measured application of throttle here) on a short-coupled wing span and lightweight airframe. Check out Clerget and Rhone to see real rotaries.

        1. Kim Armand Nielsen Avatar
          Kim Armand Nielsen

          OK, I understand: a Gnome Rhone would be complicated and quite dangerous on a motorbike =:-o
          However, is the Gnome Rhone as well as the Wankel called rotary’s?

          1. Jim Caiella Avatar
            Jim Caiella

            Yes, both are rotaries, although the Wankel is nothing like the originals. The Wankel is a rotary in the sense that its “cylinders” rotate. They are two completely different engines sharing the same name. Technically all the old rotaries are radial as well in that their cylinders/pistons are arranged radially around its center. That only describes their external appearance. It is their operation, which makes one a rotary and the other a radial.

        2. Kim Armand Nielsen Avatar
          Kim Armand Nielsen

          I’ve got this piece of eyecandy for You:

  44. uncle buster Avatar
    uncle buster

    Why not the Deltec Diesel? 36 pistons 18 cylinders delta configuration. Tough as the hubs of hell. The only blew up when pushed to 5000 shaft HP.


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  46. mcpotd Avatar

    The Kawasaki H2 750 2 stroke.

    1. Kim Armand Nielsen Avatar
      Kim Armand Nielsen

      The H2 was actual quite straight forward except from the electronic ignition and the amazing(?) power was done by the Aprilia 250 only 20 years later. Reed-valves at the intake and moveable top of the exhaust-port made it less hysterical than the 750cc H2 😮

  47. OmoBob Avatar

    You want crazy? Try the Rotorvic 1.5L V12: six air-cooled Ariel Arrow 250cc two-strokes nailed together into a single engine and inserted into a poor unsuspecting Lotus 23.

  48. Kim Armand Nielsen Avatar
    Kim Armand Nielsen

    The 4300 HP Pratt&Whitney R-4360 Wasp Major could have been mentioned too!
    Like the Napier Sabre H-engine is the design by four rows of 7-cylindered radials the last shot before jets took over!
    Additional it have an impressive appearence – Called ‘corncob among aficionados 🙂

  49. Chris Christie Avatar

    The engine, by itself, isn’t all that amazing. It’s admirable, to be sure; it’s a very small Rotary engine intended as a replacement.but the Merlin is a hard engine to beat, but if anyone is going to do it, it’s gotta be this one.nice sharing.

  50. Burnerjack Avatar

    If you’re a fan of the sohc 427, then, respectfully, I suggest you check out the 1971 Moser’Crower dohc chevy v8. FOUR! COUNT ‘EM! FOUR overhead belt driven heads! Don’t know the specs but must rev pretty high and breath like a dragon.

  51. Louren Ryan Avatar
    Louren Ryan

    I have plans of taking the Merlin and building a bike around it, and not one of those silly trike things, 2 wheels, thing will weigh half a ton but I can work it so it stands on its own without the need of a kick stand. damn I can’t wait to finish.

  52. zaborsky Avatar

    Awesome pace of engineering.

  53. Boo Avatar

    Napier-Deltic worth a mention too… Like the offspring of six Commer TS3 ‘Knockers’ and a giant Toblerone.

  54. Tom W. Avatar
    Tom W.

    Ten?!? Why limit it to ten? Have some fun with it, and throw these onto the list, just for grins: the Napier Deltic, Doxford marine engines, the Fairbanks Morse OP, (opposed piston engines were pretty common, really), the Pratt & Whitney R-4360 corncob radial, the Le Rhone rotary engine, the Nordberg stationary radial, the Nordberg Supairthermal, the EMD 16-184 X engine (really weird), the Moto Guzzi four cam 500cc V8 grand prix engine… What about insane applications? Here. I’m thinking of the EMD DDA40X locomotive, with two 16 cylinder engines under the long hood, that displaced 645 CI per cylinder. And, even though they’re still “available” (just not to the average person), modern two stroke marine diesels are seriously weird, construction wise. Look around, they’re out there! They can make that Ford 427 look pretty pedestrian. 🙂