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1951 Plymouth Hemi V6

Discussion in 'All other classic cars' started by Star Car, Dec 21, 2019.

  1. Star Car

    Star Car Member

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    On the subject of the unbuilt 1951 Plymouth Hemi V6, to what extent was it based on the 1st Gen Hemi V8 and do any output figures exist for this DOHC Hemi V6? - The 1951 Chrysler 3.6 Liter V6 Hemi (at https://www.allpar.com/mopar/V6/classic-v6.html )

    Additionally despite developing both the Slant-6 and Hemi-6 engines, could Chrysler have opted for another approach via earlier V6 versions of the Chrysler A / LA V8 engines or even developing a lower-capacity V8 akin to the Hemi-headed Daimler V8 (that some claim to be a near direct copy of the 392 1st gen Hemi V8 aside from the alloy-heads and smaller displacement - albeit with scope up to 5-litres)?
     
  2. 68RT

    68RT Well-Known Member

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    Other than hemi head, it is totally different head design that would not breathe as well based on intake/exhaust angles. Would only need one shaft per side though. Would need odd angle boring as valve plane is not in line with perpendicular axis.

    /6 was developed as a low-cost 6 with a lot of design that could be made inexpensively. Tilting of the engine came from need to fit into Valiant low hood design. Reaped benefit from extra room allowing intake design to be moved out and runners more even.
     
  3. Star Car

    Star Car Member

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    Understand, seems a shame nothing became of it given the potential value of a shorter Hemi V6.

    While the Slant-6 had a lot of untapped potential (including smaller Slant-4 and diesel/turbodiesel variants) as mentioned in the Allpar article (along with hypothetical scope for a more compact Slant-4 based all-alloy V8 composite analogue to both the Daimler V8 and 215 Buick V8), a case could have also been made for an earlier more compact Chrysler LA V8-based V6 that would have been more widely utilized by Chrysler's then domestic and international branches (providing the LA V8's displacement was capable of being reduced from 273 cubic inches to something closer to 244 cubic inches or under equating to a ~181 cubic inch LA V8-based V8 akin to the 181 Buick V6).

    A number of Chrysler's existing engines were either too long and large for wider applications across its sub-divisions making them unviable or requiring models being lengthened to properly accommodate the existing engines, the likes of the Sunbeam Tiger, an experimental four-barrel 238 hp Humber Sceptre V8 (mentioned in Jensen V8 by Mark Dollery) and Chrysler Centura being a few that come to mind. Whereas a more compact production V6 would have been an asset to Chrysler for greater usage across its domestic and international branches once it realises it needs to downsize its models (and a LA V8-based V6 could in theory serve as a stop-gap precursor to the 3.3/3.8 V6 for the V6-engined K platform models beyond the belated 239 V6).
     
  4. voiceofstl

    voiceofstl Well-Known Member

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    isn't the 273 roughly the same size as all other LA emgines? To make a physically smaller v8 would have taken a whole new engine desig.
     
  5. Star Car

    Star Car Member

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    Meant to say "~181 cubic inch LA V8-based V6 akin to the 181 Buick V6".

    Cannot say merely querying whether there was scope to reduce the displacement of the LA V8 below 273 cubic inches as was the case on rival small-block V8 engines that reached capacities as low as 215-265 cubic inches.

    The allpar page on the LA V8 makes mention of an alloy block version displacing around 270 cubic inches and was to power a stillborn A-body DeSoto (with suggestion the 273 was originally intended to feature an alloy-block as opposed to an actual reduction in size) though nothing else.

    If it was possible to reduce the displacement of the LA V8 below 273 (say 244 at minimum), it would have also allowed for more reasonable sized LA V8-based V6s with wider applications throughout Chrysler's subdivisions.
     
  6. voiceofstl

    voiceofstl Well-Known Member

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    a v6 was made from the 318 for the Dakota
     
  7. GLHS60

    GLHS60 Well-Known Member

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    Looking back on Chrysler Engine design and production, its obvious they concentrated on OHV V8's.

    It appears they put their eggs in the "Hemi" basket with 3 versions, Chrysler, DeSoto and Dodge.

    All were totally different with no parts interchangeability, rather bizarre when one thinks about it.

    Not to forget the 1950 100+ day strike that is reported to have cost Chrysler over a Billion Dollars.

    I would guess Chrysler was trying to cover all bases with the 3 totally different Engine's offered.

    Displacement also varied greatly starting at 241 for Dodge, 276-7 for DeSoto and 331 for Chrysler.

    Dodge increased to 270-315 and 325: DeSoto to 291-330-341 and 345: Chrysler to 354 and 392.

    All told a very diverse lineup when using today's lingo, many sizes and types, for many applications.

    Included in this giant lineup were Chrysler and Dodge Polyspherical Engines based on their Hemi's

    DeSoto got left out of the Poly lineup and used Dodge versions when needed.

    Plymouth only got a V8 in 1955 and it also was a Dodge Poly at first until its new Engine appeared.

    You guessed it, the Plymouth A series was yet another Engine, different from the other Polys!

    By 1960 the A series was the last Poly standing and used when 318 CID was adequate till 66-67.

    1958 began another Engine family the B and RB with 350-361-383-400-413-426 and 440

    B/RB featured conventional wedge heads so only the Plymouth retained an exotic spherical design.

    And then the Aluminum and Cast iron slant 6's came along !!

    I think Chrysler resources were probably strained designing, casting, machining, building the above.

    Personally I would have preferred improvements the A series head rather than replaced by the LA.

    While the LA was a fine Engine their wedge heads were a conventional compromise.

    The Poly head design evolved into the Chevy 396 and Ford 351C and 429.

    The Chrysler Poly had great valve angles but ports that were just adequate for small Engines.

    Chevy and Ford capitalized on the excellent design and went all out on port volume.

    Ironically, the only Engine the aftermarket forgot to build a high flowing AL head for was the Poly.!!

    Its easy to look back and lament what could have been but so many factors are involved.

    When Chrysler introduced Firepower for 1951 Ford was still selling Flathead V8's!!

    Chevy and Pontiac didn't get OHV V8's until 1955, Buick 1954 and Cad and Olds 1949.

    As good as the V6 might have been, 1950 wasn't ready for it, even though it was a 60 deg Engine.

    1962 wasn't ready for the Buick V6 either so it got sold to Jeep then bought back around 1976.

    By 1986 in evolved into a pretty good Engine, proving enough time and money can polish a turd .

    Thanks
    Randy
     
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  8. dana44

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    We are mostly debating a traditional car ownership and the individual brand names, the different Hemi engines were a shared design between them in comparison to the difference overall of each brand and clientele. The first generation Hemi was an expensive monster because of their mass and castings, and the materials used were overall higher quality and more expensive metallurgy to make them work. I am not sure what the actual numbers of these Hemis were produced, but they are probably equivalent to the Hellcat numbers in relation to the other assembly line numbers, which does turn them into those rare engines we all love but could only dream about.
    Can you imagine a slant 6 with a Hemi head on it? The engine would have to practically sit flat and have both motor mounts on one side of the block to do what the slant six does in order to clear the hood. Would be cool, but would have been difficult.
     
  9. GLHS60

    GLHS60 Well-Known Member

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    The factory Chrysler non slant Hemi Six canted valve design seems similar to the side view of 1951 V6

    Apparently it was a well loved pushrod OHV Engine used for many years, approx 1970-81

    Somehow it fit Valiant sized cars,

    Thanks
    Randy
    [​IMG]
     
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  10. Star Car

    Star Car Member

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    Am aware of the LA-based V6 in the Dakota, of the view however such an engine could have appeared earlier.

    If Chrysler became that over stretched in the post-war era putting resources in various projects as well as dealing with strikes, how could they have better approached rationalizing things while at the same time developing engines with much wider applications even across the Atlantic and in other non-US markets as was the case with both Ford and GM?

    While conceding the Hemi V6 was likely too sophisticated for the 50s era, Chrysler could have developed a more conventional OHV version of the 60-degree V6 (with scope for Aussie Hemi-6 like developments), an early-60s LA V8-based V6, a more compact V8 inspired by the Daimler V8 or via a more expanded modular-like Slant-Six range perhaps even a 90-degree V6 derived from a hypothetical production Slant-Four based V8 (if not a 60-degree V6 that carries over much of Slant-Six's architecture or related V6 with Aussie Hemi-6 elements).
     
  11. GLHS60

    GLHS60 Well-Known Member

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    All valid points for discussion but its easy to second guess prior decisions made decades earlier.

    Studebaker introduced a fine 232 CID V8 in 1951 but the market wasn't impressed.

    Chevrolet introduced the Pancake Corvair six in 1960 but the market wasn't impressed.

    Pontiac offered a slant four four in 1961 but the market wasn't impressed.

    IHC also offered a slant 4 in 1961 but the market wasn't impressed.

    Chevrolet offered an inline 153 CID in line four in 1962 but the market wasn't impressed.

    Jeep offered an OHC inline six in 1962 but the market wasn't impressed.

    Buick and Olds offered aluminum 215 CID V8 Engines in 1961 but the market wasn't impressed.

    Buick offered a V6 in 1962 but the market wasn't impressed.

    Pontiac offered an OHC inline six in 1966 but the market wasn't impressed.

    Chevrolet, Olds and IHC offered Turbocharging in the early 1960's but the market wasn't impressed.

    What impressed the market was cast iron OHV pushrod V8's in assorted sizes.

    What I think Chrysler was doing during this time period was trying to figure out what to do.

    Chrysler finally settled on A and B series V8's and converted the flathead 6 into Slant 6's.

    Slant 6's were converted into the Trans 4 family of 2.2/2.5 and eventually 2.0 and 2.4.

    A far better Engine than the 1/2 V8's from IHC, Pontiac and even the Iron Duke, 1/2 of a 301 V8.

    No need to even mention the Vega 2300 or the Olds Quad Four, the market wasn't impressed.

    Ford did better than GM with the OHC 2.3 and even the OHV 2.3 derived from their inline 6.

    Fords Cologne V6 proved to be a window into the future enjoying all the benefits of a 60 deg V6.

    There was even a V4 versions but the 2.8 and 4.0 were the most common in N/A

    However, Ford didn't even know the future was in 60 deg V6 Engines.

    Ford also built a 90 deg V6, (3.8, 3.9, 4.2) not a cut down Ford V8 but a direct copy of the Buick 3.8!!

    For sure, I'm not picking on the domestics, it's just that I followed along.

    The others made plenty of poor designs as well!!

    Thanks
    Randy
     
  12. 85lebaront2

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    Randy, I am going to correct you on one and add some Buick's first V8 was the 322 nailhead installed in the Roadmasters, Supers and Centurys from 1953-56 and in Specials in 1956 in 1954 they brought out a 264 for the Specials for 1954-55. Packard, the last of the luxury independents didn't have a V8 until 1955 when they introduced the Patrician and Clipper V8s, 352 for the Patrician and 320 for the Clipper, somewhere in 1955 the 320 Clipper engine was replaced by a 2 barrel version of the 352 which was sold to AMC for The Hudson and Nash senior models and their sister Studebaker for the Golden Hawks 1956 Packard enlarged their Senior V8 to 374 and put 4 barrels on the 352 for the junior series and continued to sell engines to AMC and Studebaker.

    In 1957, after Packard's demise, AMC was left with no V8 so developed their own, a 327, preceding Chevrolet's 327 by 5 years, It was installed in the Rambler Rebel. An interesting fact, the head castings had a joined HN cast inside the valve area.
     
  13. GLHS60

    GLHS60 Well-Known Member

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    Great!!

    I wasn't sure if anyone even read my posts and I don't mind any corrections.

    I'm generally interested in the history and how things happened to happen.

    Thanks
    Randy
     
  14. Star Car

    Star Car Member

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    Randy. It was not my intention to run down Chrysler's engines and as you have mentioned Ford, GM and others also had their own mistakes.

    Rather from a Euro-focused what-it / alternate history POV am interested to know how Chrysler could have followed a similar course to its rivals at Ford and GM in terms of engine development, which would have allowed for Chrysler to more easily integrate its international divisions via more widely utilized engines, place the company in a better position from the 1970s onwards as well as allow for a situation where Chrysler's domestic engines (albeit not limited to just V8s) could easily fit into the space of its smaller international models like the Sunbeam Tiger, Humber Sceptre, Simca 1300/1500 (which could have possibility benefited from a 170 Slant-Six derived 1.86-2-litre Slant-Four), etc (the likes of the Chevrolet Firenza Can-Am V8 and Ford Capri Perana V8 being the more extreme examples from Chrysler's rivals).

    Based on your post. It would seem in retrospect based on the Slant-Six evolving into the 2.2/2.5, that Chrysler would have been better off both developing an earlier version of the LA V8-based V6 as well as an earlier Slant-Six derived version of the 60-degree 3.3/3.8 V6 that carries over the more Euro-sized ~170+ cubic inch displacement range (if not elements from the Hemi-6) from the 1960s onwards.
     
  15. GLHS60

    GLHS60 Well-Known Member

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    I didn't think you were necessarily running down any Engines rather just talking what iffs.

    I don't think there was much possibility of international Engines until recent times.

    The N/A market demands were vastly different from most others as I remember.

    Up to about 1960 N/A customers almost entirely wanted full size 6 passenger sedans.

    A 6cyl of about 140 HP or a V8 about 200 HP was mandatory especially with an automatic trans.

    It took a "low strung" reliable Engine to accomplish this for millions of family's

    I remember very well when imports began showing up and the reliability issues that followed.

    VW was the most reliable but not that great as a family car, especially with a family on board.

    Chevrolet responded with the rear Engine Corvair, actually a decent car, but too different.

    Vastly superior to the VW in every way as a family car but the market didn't understand it.

    Chevrolet then responded with 1962 4 and 6 cyl Chevy II's though few customers bought 4 cyls.

    It was well received by the market, family's and mechanics alike, as were the Falcon and Valiant.

    Buick jumped in with the V6 but the market, family's and mechanics didn't accept it.

    Acceptable over a VW, Ford Cousul, Simca, Vauxhaull etc but inline 6 and V8's were still preferred.

    1970 was the pinnacle of domestic Engines for years as gov't reg's crippled them until about 1985.

    Development resources were spent complying with regulations until electronics became reliable.

    Without electronic fuel injection down sized Engines of any type weren't suitable for the N/A market.

    Eventually cars got smaller, heavier and better performing as manufactures got caught up to reg's.

    Today a 3.6 Pentastar will satisfactorily power a giant Ram pickup, an impossibility a few years back.

    Had gov't not imposed insane regulations way too soon things would have been different.

    However that's another topic not allowed discussing on Allpar.

    Thanks
    Randy
     
  16. 85lebaront2

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    Randy, you are exactly right. Wife's vehicle (it is classed as a CUV ) is a 2011 Ford Flex limited, engine is a 3.5L NA DOHC V6, optional on it with mandatory AWD is an Ecoboost version. The NA engine has a redline of 6500 (that's where it starts) the 6F50 transaxle (shared with GM as the 6T50) is responsive and under normal driving quite smooth. If you kick it to jump into a traffic flow or to pass on a 2 lane road, the engine is strong, transaxle will drop or hold to roughly 7000 rpm.

    The vehicle is as close as I could find to the MOPAR and FOMOCO wagons I (a) grew up with (MOPAR) or (b) owned (FOMOCO) but is much better driving equal if not better in comfort, way more economical and of course safer in many ways. Dual zone climate controls were unheard of in the 50s, 60s and 70s and are now the norm on many vehicles along with many power and convenience options including power folding 3rd row seats, a 110V power outlet, 2nd row climate controls, headrest DVD players for the 2nd row a refrigerator/freezer between the second row seats, power liftgate, navigation system, bluetooth (Sync by Microsoft) so you can do hands free phone use if needed. Safety, ABS of course, side curtain airbags, smart front passenger airbag.

    One more feature I like, the spare is under the rear floor panel inside instead of underneath like the 1989. 1993, 1997, 2003 and 2005 MOPAR minivans we owned, yes I have to move anything back there to get it out, but, I know it will come out, not like some of the minvans where the winch rusts solid and won't move or the cable rusts through and drops the spare on the road.
     
  17. dana44

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    Can you imagine the weight of a Hemi head design in cast iron on a slant 6? OMG, first gen Hemi heads in V8 are heavy to me, and I'm not a weakling by any means!
     
  18. 85lebaront2

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    I wasn't old enough 14-15 when dad did some work on the 331 Hemi in our 1953 Imperial. I can imagine what those weighed, heaviest ones I have messed with are from my truck, and they are hefty, roughly 70 lbs less manifolds but assembled.
     
  19. 68RT

    68RT Well-Known Member

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    Try pulling a Buick straight 8 head.
     
  20. Star Car

    Star Car Member

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    Would say there was a small chance for Chrysler from early-1960s to develop the sort of engines which could be widely used with little extra cost, for the LA V8 it would have been to find a way of placing the distributor at the front instead of the rear as well as possibly reducing the width / size so its fitment into smaller cars does not require too much extensive modifications to the bulkhead.

    Both of which was what prevented it from fitting into the engine bays of the Sunbeam Tiger, Humber Sceptre, Humber Super Snipe / Imperial and Chrysler Centura, though an earlier LA V8-based V6 or Slant-Six based 60-degree (or 90-degree) V6 would have probably had a much better chance of fitting into the aforementioned cars (plus the likes of the Hillman Hunter / Rootes Arrow, hypothetical US spec-180, etc) as well as being valuable to Chrysler in other markets.

    Could see such engines serving a similar role as the Cologne V6, UK Essex V6, Windsor V8 by Ford along with the Buick V6 and Chevrolet Small-Block V8 that found their way into cars from UK/Europe, South Africa, Australia, etc. In the case of Australia one would have to question the necessity of the Hemi-6 as opposed to a locally made 6-cylinder for wider applications outside of Australia that shares components with existing Chrysler engines.

    Chrysler UK did have a 60-degree V6 in development, that despite claims of it being a copy of the UK Ford Essex V6 was actually reputedly derived from the 1.3-1.6 Avenger engine (with the 1.8-2-litre Brazilian block potentially providing a 3-litre displacement). However it fortunately never appeared and had it did would have not had much of an effect on Chrysler outside of Europe in initial 2.0-2.4-litre form, unless Chrysler already had larger 2.8-litre+ V6 engines in production that could eventually be replaced by a larger V6 in 2.7-3-litre+ Brazilian block-derived form.

    Then there is the Type 180 engine by Chrysler Europe that reputedly drew inspiration from the BMW M10, which amongst other things spawned the M30 inline-6 and stillborn M10-based V8 engine. Had the engine been emissions certified for use in NA, a Type 180-based inline-6 or V6 could (like the Avenger-derived Rootes V6) have been another belated asset to Chrysler from the early-1970s about 17 years before the 239 LA V6 and some 19 years before the 3.3/3.8 V6.
     

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