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Apparently from what we read now, VanRanst's version for the FWD Packard 12 wasn't w/o significant problems.

Packard53
Who was the outside source that designed the twin 6? I thought that Col. Vincent designed and built the prototypes and convinced Packard execs to build it.

John - you did fine in your disc. of what you read on tech. info. on the 1930's era Packard V-12.

To add to your discussion, let me explain more about the layout of the combustion chamber and induction and exhaust systems, and why all this resulted in a MUCH more raw power at the rear wheels, then either of the two Cadillac V-16s (the earlier over-head valve one, and the 1938-40 "flat head") (both of which were significantly smaller than the Packard V-12.

Incidentally, Auburn, to my knowledge, did not have much to do with its own V-12. That was a Lycoming design, engineered and built in the Lycoming shops. About the size of a Packard Super Eight. Good engine - tooling purchased by American La France and, with some mods, used for many years in their smaller fire engines. But NOWHERE near the raw power of a Packard V-12 (as a side note, the Pierce Arrow V-12, about the same size as the Packard V-12, lived on clear into the early 1960's, in smaller Seagrave fire engines.

Anyway, the key to understanding the genius of Packard engineers (again, not Van Ranst - he was a DRIVE-LINE engineer - I dont know what, if anything, he had to do with power-plant design ? ? ? ? ) is to look at a cross-section of the Packard V-12.

First, you see that the top of the block is NOT directly 90 degrees to the bores. It is at an ANGLE, permitting a wedge-shaped combustion chamber. This, coupled with "wedge shaped" pistons, gives vastly superior "burn" characteristics to an ordinary "flat head".

Secondly, look at the induction system. As to the intake manifold, note that it was one of the first, if not THE first, attempts at what Chrysler, some 20 years later, called "ram induction". meaning a balanced even flow.

The Stromberg EE-3 carb. was, if my understanding is correct, the largest 'swept volume" of any automotice carb. until the four barrels of the 1950's. Thus the Packard Twelve could BREATHE. Look at how much smaller the carbs and their volume were, on any other big multi-cyl. luxury car of that era, and you can see why, bone stock, I had much sadistic fun "blowing the doors" off of other big classic car owners when we were wild kids in the first years of the Classic Car Club Of America.

Now look at the exhaust system. I am unaware of ANY production auto motor of that era where they went to such great pains to have unrestricted "breathing".

Bottom line - you got a damn good buy when you bought a Packard.

Other than my earlier comment that VanRanst was primarily a suspension/driveline guy (though he did have plenty of engine experience) I can't add anything to the discussion about the design of the 2nd Twin Six. It might prove interesting to review Packard's patents on the engine and see who were claimed as inventors. I wouldn't be suprised to see the names of one or both of the Storey Bros. among them.

But one thing that I have always marvelled at about this engine is the complexity of the casting, a single block casting in an era when most engines were designed around separate crankcase and bore castings such as the senior Packard Eights, Lincoln V12, etc. Ford often gets credit for producing the first (perhaps first high-volume)V-form single cast iron block for their flathead V8, a claim which may or may not be correct (Oakland V8 was a single piece block, was it not?), but if you read about the casting problems they had and the very large number of early blocks that were trashed because of pressing the coring/casting technology of the day past the limit, Packard or whoever designed and/or cast their blocks seems to have avoided this problem. To me that is an unheralded accomplishment.

Peter: I can think of a couple of classics of the 30's that would give your Packard a pretty dam good run for the money.

1. Duesenberg straight 8 265 horsepower
2. Marmon V16 200 horsepower.
3. Certain models of the Stutz coming equiped with the
DV 32 engine

John F. Shireman

John - you are missing the point about what Packard was all about. It produced, in my view, about the best car you could buy in any given price class it chose to compete in.

It would be just as silly to compare a Packard Six with a Packard Super Eight, as it would be to compare a Packard Twelve with a Duesenburg or Marmon. You could buy three or four Packard Twelves for the cost of ONE of those.

As a Packard buff, you can take pride in the fact that Packard products were often near as much, if as not as much car as many other make's cars that cost much more.

Next time you get your hands on a Duesenburg or Marmon V-16, look under the hood at the carbs. Depending on the year, you will see carbs with only about two thirds of the "swept volume" of the Stromberg EE-3. All the fancy engine design in the world ( The Lycoming engine in the Duesenburg was pretty advanced, but in many Dusenburgs CRIPPLED by the smaller carb, they just couldn't BREATHE).

So of course the clearly RACING type engine of the Dusenberg (four valves per cyl., over-head valves with cross-flow heads, etc) made them faster than a Packard Twelve, but, depending on how they were set up and what bodies they carried. not by all that much. (UNLESS you are talking about one of the later ones which WERE also equipped with the same Stromberg EE-3 as the Packard V-12 used.)

Same goes for the Marmon. Bigger displacement motor in, in may cases, a MUCH lighter car. I road-raced a couple of times a friend of mine who had a Marmon V-16 coupe. Of COURSE he pulled away from me, but not by all that much.

The bottom line was that Packard was a success, and Marmon and Dusenburgs were failures in the market-place. Take a look at the photos of fancy diplomatic receptions, operas, estate parties, etc. And look at the sales figures. The big Packard outsold by many times EVERY other make ANYWHERE in the world. The wealthy car buyers of that era, test-driving a Packard Twelve, a Cad. V-16, Duesenburg, or Marmon, made their choice for good reason. A PROPERLY MAINTAINED Packard is by any COMPETENT writer who KNOWS what they are talking about, by far the most pleasant to drive.

Judging by what the Packard philosphy was all about, I believe that had Packard chosen to compete in the same price class as the Marmon V-16 and the Duesenburg, they would have been hopelessly out-classed by the Packard product.

Peter: I already know the quality of cars that Packard produced even through the 50's till the end.

I would like to point out that you were the one that brought up the subject of your Packard blowing the door off
of other classics. I nearly listed some classic that might blow become some real competition for your Packard.

In neither case was Duesneberg or the Marmon V16 failures.
E.L. Cord intended to keep the sales of Duesenberg very limited. The 1929 stock market crash made sure that sales would be very limited.

When the Marmon V16 was introduced the parent Marmon company was just about on the ropes again because of the 1929 Depression.
To state that the Marmon V16 and Duesenberg were failures is just plain nonsense.

Had not Packard come out with the 120 in 1935 which saved Packard from going out of business. Your statement could well be applied to the Packard V12.

I am really sure that being rated at between 245 and 265 horsepower the Duesenberg engine wasn't that Crippled.




John F. Shireman

Peter: Your statement you made that in many cases the Marmon V16 was lighter than the Packard V12, isn't quite true.

Granted the 490 cid Marmon V16 was a bigger engine than the Packard V12. The Marmon V16 engine weighed in as about 935 lbs, this weight included the complete engine block and transmission. Which is considerably lighter than the Packard V12 engine.

The Marmon V16 which was produced between 1931 and 1933 had weights of between 5050 to 5440 lbs. With the Packard V12 being produced between 1932 and 1939 had weights of ranging between 4950 to 5950 lbs.

John F. Shireman

The Packard V12 did indeed have the valves tilted toward the cylinder. This gave many advantages.

1)Better breathing as the fuel/air mixture had a more direct path into and out of the cylinder.

2) Better cooling and better compression. The valves could be close to the cylinder, yet there was room between the valve and cylinder for a cooling water passage in the block. The typical flathead design forced the designer to choose one or the other, close valves for more compact combustion chamber and higher compression or farther away for better valve cooling, Packard had both.

3) Higher compression thanks to the smaller combustion chamber.

The top of the block had to be milled at a slant to the cylinders, and the cylinders had a wedge shaped combustion chamber as did the supposedly more efficient OHV V8s of the 50s. But the V12 kept the advantages of the flathead (simplicity, silence, reliability, compactness, low cost) while being practically as efficient as an OHV.

Packard straight eights had a similar design postwar with the valves tilted toward the cylinder. So did Hudson's last big 6 in the 50s. These were probably the ultimate flathead production car engines. They both gave the OHV V8s strong competition.

As for the ram air or heated air question perhaps you are thinking of an intake heating system used for quicker warmups and better drivability when cold, sometimes known as a heat riser valve?

If I might just jump in here, the earlier question I posed brought a wealth of information. I was indeed asking about the "second" Packard V12, which for some marketing reason was sometimes referred to as a "Twin Six" although it was a completely new design. The first Twin Six was enormously popular and put Packard front and center for American automobiles, coming out in the early early days around Springtime 1915 (John, I won't argue with you, neither of us was there.) But as impressive as the first engine was, I really wanted to find out more about the Second Packard V12, which has always been kind of shrouded in mystery for me. Even its engineering team and first production date are sort of hard to determine. It's "That 30's Packard V12."I did find out that the last of the original "Twin Six" are believed to have been produced by June 1923.

I posted here in hopes of confirming or debunking a suggestion I read elsewhere that... aw heck, let's just call it the "2nd Generation" Packard V12... had an early version of what could be called "Ram Air" and/or a "wedge" head. I find the answers here to be mostly positive, especially from packard V12Fan (considering at first you posted that you didn't know exactly what I was asking, you certainly nailed it in your answer later on).

I guess that you could say, rather than a "wedge head" the 2nd gen Packard V12 had a wedge-shaped combustion chamber. And with all surfaces machined, to boot. Talk about polished and ported! You could give Packard quite a bit of credit for realizing how important it is to allow an engine to breathe free to get the additional "free" power out of all those cubic inches. I'm often shocked at the tiny carbs and intakes on those monsters, (and also restricted exhausts). I imagine the engineers aimed more at smoothness and silence, and sacrificed power. The thing I've always liked about Packard is the payed attention to BOTH luxury and performance.

But I wonder how come it took Packard almost a decade--during the "Roaring Twenties" no less--to begin producing a new V12 after they had become famous for their first effort. And then when it came along about 1932, it came with so little fanfare for so much innovation, while the "Light Eight" seems to have been favored. Even Alvin Macauley is said to have referred to the 8 as the more important introduction of the year. Their timing for it wasn't the best, it's true, but then why did they wait so long?

In addition to the fact that I was pretty sure of getting knowledgeable answers here, I made this post because of the site's great collection of literature, pictures, and possibly engineering drawings that could be unearthed or contributed in regard to this engine... the LAST of the Packard V12's.

(I still can't quite visualize the valve setup, and the exact shape of the combustion chamber, was it a continuous wedge or more of a peak design?)

Thanks for all your input.