Packard Forum Index » Pre-War (1899-1942)

Hello Everybody,

First-time thread on this board. Some of you may remember me from the Packard forum on AACA. I have been reading PackardInfo with a lot of enjoyment for some time. The amount of original information is incredible.

A question came a while back about Packard's venture into a new V12 around 1932. I say "around" because I believe the intro date was April of '32. The question was, did this engine have a "wedge" head design, and did it incorporate a forced induction system, like passive "ram" air?

I have found some mention of what would now be called a "cold-air intake" system and pre-heated fuel on the "Light Eight" engine to take advantage of some free HP, but nothing on the newer V12 design, which seems to have been introduced with less fanfare, yet was much more advanced than the older, more famous "Twin Six."

Also, I understand that the original Twin Six was produced from (approximately) 1914 to 1923, leaving Packard without a V12 for almost 10 years?

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G'day and welcome aboard the Site. If you haven't already done so could you please add your Packard/s to the Owner Registry with pic/s, and known history/s?

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That's great, very comprehensive and a pleasure to read. Look forward to seeing your Clipper as it progresses.

Specifically, what precisely would you like to know about Pacakrd twelve cylinder technology ?

55 Packardguy: The first Packard Twin 6 was introduced to the public in May 1915. The same time that National introduced their V12 engine to the public which they called the Highway 12.

The second generation Packard Twin Six was introduced to the public in January 1932. Shipment of the new Packard Twin Six started in April 1932.


John F. Shireman

Packard53, to try and answer your initial inquiry. I'm not a V-12 expert, but much has been written about the later twelve cylinder engines and the cars they powered. The second generation (1932-1939) V-12s had a unique and interesting valve design. The camshaft and roller tappet/lifter design had the valves sitting relatively high between cylinder banks. The valves intersected the cylinders at an angle that resulted in them being more perpendicular to the cylinders rather than parallel as is typical with a valve-in-block (L-head) design. This coupled with a pent roof piston and flat cylinder head (I believe) resulted in a combustion formed formed by the piston, valves, and a relief in the block and not by a formed chamber in the cylinder head. This design provided for fully machine finished combustion chambers. As far as I know there was no forced induction with these engines. All of this is from my recall, and I may be mistaken in some parts of this description. I also believe that the Auburn V-12 had a unique, but different valve design where the valves were not horizontal with the cylinders. There are many V-12 experts on this site that can quickly correct what I have said.

Ooops. The above should have been addressed to 55PackardGuy and the reference to the valve location for the Auburn V-12s should have said: "...where the valves were not parallel with the cylinders."

One thing that most is most puzzling to me about the evolution of the the second Packard Twin Six. With all the experience that Packard had in building all kinds of engines.

The basic design of the Twin Six came from an outside source hired by Packard. The basic design of the second Packard Twin was done by Cornelius Willet Van Ranst.

John F. Shireman

John, I have no real information on VanRanst's contribution to the Twelve engine per se, but can say that all of his patents assigned to Packard Motor Car Co. that I've seen dealt with driveline, suspension and transmission. For a little insight into VanRanst's inventiveness, you might want to read US 2,098,265 filed 3/31/32 titled "Design for Front Wheel Drive". You can get this from the U.S. Patent and Trademark Office. Packard's most prolific patenters in the 30s and 40s were W. R. Griswold and Clyde R. Paton.

It's a bit off the topic but you might enjoy looking at the enclosed table of some of the U.S. patents Packard claimed as relevant to the 1942-47 cars. This exerpt is from an article I had published some years back in The Packard Cormorant .

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Which is a modified version of Harry Armenius Miller's patent for front wheel drive, the difference is that Harry's version had the transmission on the output side of the differential, whereas VanRanst's version did not. Harry's wasn't a very successful version, but VanRanst's version worked very well in the L29 Cord's.