Is the experimental slant six with four rings an urban legend - or did I get the real story?

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garyyouree

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I was talking to a guy about a 63 pontiac I had bought with a transaxle. After I finished about the broken 1" tube torque drive shaft, the stupid design of a separate parking lever on the dash - and how easy it was to put the car into drive while in park - breaking the shaft ... then a quick recent story about a Dodge ... he returned with a Dodge slant six motor story. It is an excellent story and I had no reason to believe this guy would lie - but I did not really know him and I know how people will pass on urban legends as their own stories. Let me know if you have any information - legend, truth, or lie?

This was 25 - 30 years ago. I was trading car stories with this guy and started with the one above - about the pontiac transaxle. Then I told him about an incident a week earlier where i had purchased a 25.00 Dodge Dart slant six with a rod slapping around. I had taken it as a driver - planning to eventually walk from somewhere - steel was worthless back then.
I was on the highway, the knock got louder and louder, I was about 10 miles from home, and the piston shot out the side of the block. I watched it bouncing down the highway in my rearview.
I pulled over, the car was still running, and opened the hood. There was a piston head sized hole right in that exposed side of the slant six block - and it was shooting fire out of it.
I got back in the car and believe it or not - it made it the 10 miles home. I shut it off and it was locked up the next day. Tough motor.

Anyway - THE STORY: He says, "speaking of the slant six - have you ever heard of an experimental motor, a slant six, with four rings that was built extra heavy duty?
I said "N0" and he told me: I bought this 67 Dart with a slant six from my dad who had bought it used. His dad had told him the car had at least 200k miles on it according to the guy he bought it from.
His dad drove the car from 1974 to 1983. He never had a motor problem and put 300k miles on it - then gave it to his son (the guy telling me the story). So Rob gets the car and it has at least 500k on it. Brakes had been done a few times. Seven sets of tires. Etc. But nothing with the motor.
He drove it for 4 - 5 years putting another 125k on it. Now we are up to at least 625k miles. More brakes and tires.
The car has a hard time starting. It is popping and missing. He figures it is the timing belt. He figures he will pull the motor and rebuild it.
Then he finds a double timing chain. The head have more bolts than the manual says it should. He has bought a rebuild kit and not everything is right. His motor has 4 piston rings. He goes to a salvage yard and looks at another tore down slant six. His looks like it came our of a tank compared to the one in the yard.
He takes the kit back to the store and says he must have got the wrong one. The guy says there is only one for what he is talking about. He gives them a six digit number and the guy says it is too short. It ends with an EX.
The guy knows slant sixes and says I have no idea.
So he calls dealers, hemmings, etc. and finds out nothing. He looks at the ID plate and calls the plant it was made at.
He gets passed from person to person, until he gets on who is real interested and wants to know his address. He gives it hoping they are going to help him.
They come out with a wrecker and just take it from him. He cant get an answer from either driver - but they give him a check for 500.00.
He tells them he would rather keep the car. Neither chain is broke, just loose, and he can buy two factory chains and they will fit. It does not use any oil.
They tell him to keep the check. The car is "illegal" and should never have been on the road. " They gave us paper work to show it is stolen and told us, to tell you, we dont have to pay you anything - if you have a title it goes to another car. If you cause trouble you wont get the check. Take the check - because we Have to take the car.
They loosen up a little and tell him all they know. There were told to go get this car. It was never supposed to have left the factory but an employee who was allowed to use the car for a year in a practical demo never returned it - and had quit the job. There had been a lot of scuttle butt ever since he had called them and one old employee, before he was told to keep quite, said it was an experimental slant six they called the million mile motor. Extra heavy block, two oil rings, two timing chains, double geared, and a few other things I don't remember (something about the piston pins, heads, and valves - hardened gears). They had only made 6. Put one one on the road with an employee and a couple ran on stands for a few months. They were all eventually scrapped. The military application was the tow drivers guess. Only one motor made it into a car, the 67 Dart, out the door and into a possibly answered history.

Their guess was that it was an experimental engine - possibly for military applications and never intended for the general public - but that was their personal speculation.

My friend with the story thought it was an experimental motor designed by some engineer who had the pull to get it built. His guess is that a motor that would out last the car would make for unsafe cars on the road. His speculation.

My usual paranoid explanation is that they can always design motors like this - but don't because there is no profit making something that does not need replaced. Some high level engineer got the funds to build the design for this million mile motor - with the intention of scraping it.

I remember my grandad, born in 1887, showing me a light bulb he was still using and had used for 50 years. He said when I got it from a friend he threw it to me from across the warehouse where he worked (and they made light bulbs) and it bounced up to him. It had a rubber like coating with a filament that would never burn out. He never saw it on the market. I wish I knew what happened to that bulb. That was 55 years ago.

So - tell me, " the first time I heard that one...." or, more fulfilling, "yeah, we had some of those in the army"
 
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Some engines (not specifically) do use 4 rings. The problem is there is a trade off. They create more friction, so are not a high rev engine. Mostly torque, low speed, industrial/ truck stuff
 
The four ring slanties were usually stationary, or pump engines. The ran at low RPMs 24/7 365 days a year, I bought one to replace the 225 in my 63 Dart, a friend of the family installed it for me. I went to pick it up after installation, It ran better than it had ever run in the past. I finally ran the numbers at my local Mopar dealer. Low & behold, it came back as an industrial pump engine.
 
An arborist was at my property and saw my Barracuda, and mentioned they used to have a wood chipper powered by a slant six. So there's another application.
 
So the men in black showed up in a black tow truck and just took it from him? Sounds like the GM EV1 when they were all hunted down and crushed. Good story, maybe a little drama added for effect. I didnt think the industrial slants had more head bolts....?
 
Yeah, I think there was a little icing on this cake...
 
well they did put a 6 in a tank, actually it was 5 6's bolted into a radial pattern!
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So the men in black showed up in a black tow truck and just took it from him? Sounds like the GM EV1 when they were all hunted down and crushed. Good story, maybe a little drama added for effect. I didnt think the industrial slants had more head bolts....?

It is starting to sound like he might have embellished the story - which probably means it was never his story. Thank you all for the feedback. I have wondered about this, now and then, for years
 
Ever tried to call Chrysler?
I used to work at a Mopar dealership. We had direct contact phone numbers.
Trying to call Chrysler and actually getting thru is a feat.
Finding someone who knows anything about a car thats more than 10 years old is impossible.
 
was chatting with buddy yesterday and /6's came up he telling me bout farm equipment combines and stuff that came with /6 power out in iowa, thought that was cool
 
was chatting with buddy yesterday and /6's came up he telling me bout farm equipment combines and stuff that came with /6 power out in iowa, thought that was cool
Yes. Oliver used slant 6's where as Deere used 292 Chevy 6's in the early self propelled combines.
 
Yep. I worked on a diary/ hay farm in the 80's. They had a combine with an industrial slant six in it.

Were there ever any marine slant sixes?
 
Yes there were marine slant sixes. IIRC the first 2bbl intake was a marine intake. SS Dan would know reams of info. They put a "flat" six in a boat under the seat, it was a slant that was on its side to keep its profile low. Had a strange oil pan that was about as you would think with it laying on its side.
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Wow. Thanks for the pic - very cool>1125ci. Wonder how they connected all those cranks? Probably 5 distributers?
i had my own business i started back in 83 when i was nearly 30. Started with the proverbial one pickup (IHC one tone). We recycled pallets at first, expanded into cardboard, traded odd sized pallets for native stone, started making colored mulch from the final scrap (after using machines to dismantle odd sized pallets for repair lumber and lumber to build new pallets from used lumber), and then finally trucking - as this became a big cost.
Since for the first 10-15 years the deliveries were in the three state corners area (AR, MO, OK) (I was in NW AR) I stuck with all used equipment since I had my own wreckers (I would tow the load to the customer before taking the broke down truck home).
Started with old two ton IHC trucks; B210's from farm auctions. I had more than 20. Then got smart and went to tractors. Stuck with R190 and R200 IHC's. They would have these huge 501 and 450 straight 6's. I had several wreckers. Accumulated hundreds of trailer vans 40' to 53'. It was a way to avoid taxes and for what I paid I could always sell them for the same or more as storage vans down the road-which i did (but glutted the local market so bad I had to sell nearly a hundred for scrap).
The point was the GMC V12 built off the V6 design. I had a huge truck salvage yard I visited on a regular basis. It was 40 acres of trucks from 55 - 69. I was looking around and found a whole fleet of truck tire delivery trucks with these V12's. It was its own motor but interchanged parts with the V6. used one distributer, one gear, but two caps. Two manifolds with two one barrel carbs that looked like coffee cans.
I looked it up the other day and found pics where it had been adapted for racing - all chromed out - it was something.
I once put a 62 V6 GMC with a Clark 5sp into a 2002 Silverado when the 454 went down. It had a problem of rolling off in gear due to the gear ratios of the rear end and the trans.
If I had took the final step on changing out the rear end with the two speed, and the front axle, suspension, so i could run on 20" truck wheels I might have had a conversion production project. There were a flood of one ton GM trucks to be had with bad diesel 6.2 and 6.5 motors laying around.
Thanks again. Did receive a reply that the four ring two timing chain was a slant six used in industrial machines. It was a second hand story which was probably borrowed - which means it was probably embellished. I do believe a high ranking employee put an industrial slant 6 into a new car on the production floor - and possibly kept it illegally... and it could have been towed for that.
 
Yeah, I think there was a little icing on this cake...

LOL - I suppose i could have said they came out with an industrial portable crusher and left him a cube in the driveway - while 4 black helicopters hovered overhead.
Looks like it started with a kernal of fact - the motor exists. Most likely a car executive got one off the floor with an industrial motor and never intended to be resold.... or a guy just got a used car that some one had put an industrial 6 in it and when he went to get parts they didnt have any info on the industrial 6's... from there it went like a game of creative telephone. All I added, from what I had been told, was additional head bolts (felt guilty stupid right after I hit post)
 
Looks like flat head 4 or 6s? I wonder how the sumps work? Common sump? Definitely interesting.
Gears. Each crank had a gear on it which drove one central gear. And yes it had five distributors.
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I have a 6600 New Holland haybine with a /6 industrial and a hydro drive. Runs like a Swiss watch.
 
well they did put a 6 in a tank, actually it was 5 6's bolted into a radial pattern!
View attachment 1715056579
Found this
Chrysler A57 Multibank Tank Engine
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By William Pearce

When the United States entered World War II, there was a desperate need for a medium tank engine. Chrysler responded with a very unique idea. Chrysler had its 251 cu in (4.1 L) straight six-cylinder, L-head engine available in large numbers. Under the direction of Executive Engineer Harry Woolson, the Engine Design department, headed by Mel Carpentier, designed a new powerplant that utilized the 251 cu in (4.1 L) engine. The basic idea was to combine five of these six-cylinder engines into a five-bank, 30-cylinder, single engine for medium tanks. This new engine, referred to as the Multibank, was given the designation A57.

chrysler-a57-multibank-front.jpg

Chrysler A57 engine as displayed at the Walter P. Chrysler Museum. Note the central water pump feeding the five engine banks, the individual distributors for each engine bank, and the row of carburetors at top: three on the left and two on the right.

The Multibank A57 engine had a large cast iron crankcase that formed the central structure of the powerplant. Five Chrysler 251 cu in (4.1 L) six-cylinder engines were bolted to this central crankcase. Two of the engines were bolted to the lower portion of the crankcase, one on each side, with their cylinders angled 7-1/2 degrees above horizontal. Two addition engines were bolted to the crankcase above the first two, with their cylinders 27 degrees above horizontal. The fifth engine was bolted vertically at the top of the crankcase. The five six-cylinder engines made up the banks of the A57.

The A57 engine was mounted in the rear of the tank, and the crankshaft output flanges faced the front of the tank. The A57 retained the five crankshafts of the five six-cylinder engines. A drive gear was coupled to the crankshaft of each engine bank. These five drive gears meshed with a single, central gear (all gears had herringbone teeth). The central gear drove the output shaft of the power plant. The output shaft went through the radiator and drove the cooling fan and clutch, which was attached to a drive shaft and then transmission.

chrysler-a57-multibank-gears.jpg

A view of the gear case revealing the central drive gear that is driven by five outer gears, each coupled to their respective engine bank’s crankshaft. (Adrian Barrell image)

The A57 was originally equipped with five belt-driven water pumps. However, the belts would often break because of the alternating loads on the crankshaft pulleys. The design was changed to a single water pump with five outlets (one for each engine bank). This single water pump was driven by an accessory shaft from the central drive gear located on the opposite end of the central crankcase. Also at the rear of the tank, each engine bank had its own ignition coil and distributor that was gear-driven from the camshaft.

The first production engines had a single-barrel carburetor mounted directly on the intake manifold for each of the five engine sections. The different pipe lengths and contours leading from the air cleaner to the carburetors resulted in unequal fuel distribution. Metal vanes were added to direct airflow, and ultimately the five carburetors (each connected to its respective engine with a downpipe) were relocated in the same plane above the engine. This change simplified throttle linkages, the air cleaner arrangement, and maintenance.

The A57 Multibank had two oil pumps located in the central crankcase. One oil pump was a scavenge pump to transfer oil to a remote reservoir. The second pump was pressure pump that took oil from the reservoir and delivered high-pressure oil to all five engine sections.

chrysler-a57-multibank-installation.jpg

The 5,244 lb (2,379 kg) Chrysler A57 engine package being installed in a M4A4 Sherman tank. Note the engine’s size in comparison to the installers.

The A57 engine had a 3.4375 in bore and 4.50 in stroke, giving a total displacement of 1,253 cu in (20.5 L) from its 30 cylinders. The engine produced 445 hp (332 kW) and 1,060 lb ft (1,437 N m) of torque at 2,400 rpm. Given the arrangement of the engine sections, the Multibank was a relatively short but heavy engine, weighing 5,244 lb (2,379 kg) including radiator, cooling fan and clutch. Construction of the A57 utilized existing tooling from the 251 cu in (4.1 L) Chrysler six-cylinder engine, and the engines shared cylinder blocks, cylinder heads, pistons, connecting rods, and crankshafts.

On 3 June 1942, nine months after the initial engine discussion, the first of 109 M3A4 tanks were built with the A57 engine. However, the M3A4 tank was quickly replaced by the M4A4 Sherman tank, the first being produced on 30 June 1942. From April 1942 to September 1943, 9,965 Chrysler Multibank engines were built; 7,500 engines were installed in production tanks, and the remainder were built as spare engines. The A57 engine proved to be a very durable, reliable, and efficient power plant for medium tanks. Reportedly, the engine would still run with two of the five engine banks disabled from combat damage.

A number of Chrysler A57 Multibank engines survive, and some are still in working order in restored tanks.

chrysler-a57-multibank-side.jpg

Side view showing the relatively short length of the of the A57 engine at the Walter P. Chrysler Museum.

While similar engine concepts, no direct relation has been found between the Chrysler Multibank and the Perrier-Cadillac 41-75.

Sources:
Chrysler Engines 1922-1988 by Willem Weertman (2007)
 
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