Packard_Marine_V12_1350HP.mpg

This WWII Packard Marine V12 lives on today in a competition pulling tractor. It's other two brethren from the same PT boat (one with a hole in the side) also exist as spares. It's present owner rebuilt it from scratch years ago, and learned as he went. It is fed aviation fuel by twin Predator carburetors, through a custom built aluminum plenum manifold to the supercharger.

These engines sound unlike any other V12, were a "clean slate" design, and do not come from other designs.

From elsewhere on the 'Net:

"Despite the commonplace assumption, the new-generation Packard marine engine, initially tagged the 4M-2500, was anything but a re-popped Liberty V12. Instead, Vincent, Packards lead engineer, started with a clean sheet and designed a four-stroke, 60-degree V-12 with an aluminum block with a bore of 6.04 inches and a 6.50-inch stroke, which brought it to 2,490 cubic inches. Weighing 2,900 pounds, the 4M-2500 had four valves per cylinder, a 6.4:1 compression ratio, and a centrifugal supercharger, later models were also fitted with an intercooler. A Holley 1685F aircraft carburetor supplied the fuel, 100-octane gasoline, fired by two spark plugs per cylinder. The first engines developed 1,200hp, but improved versions with higher boost levels nominally made 1,500hp. Packard built 14,000 marine engines during the war, three of which went into each of the Navy's 768 PT boats, two astern and one amidships for better service access. "

Packard built many thousands of engines prior to the second world war including car engines, of course, and the famous "Liberty" V12 aircraft engines and Packard's own developments and patents and other developments and inventions by the likes of General Electric on superchargers went into the development of the Packard marine engine that were produced in their thousands during the war to power the U.S. Elco and Higgins PT Boats and the British Vosper MTB's (Motor Torpedo Boats).

The Packard 4M 2500 engine powered most, if not all, of the US built PT Boats. The pre and early world war II engines developed some 1200 brake horse power, this had been increased to 1350 BHP and then by the end of the war 1500 BHP, therefore a late war Elco 80' PT had three engines producing a total of 4,500 brake horse power and could guzzle 5000 gallons of 100 octane aviation fuel in one night of operations. The cruising speed of the Packard was stated as 2400 rpm but note that the Elco "dashboard" tachometers show a top speed of 3000 rpm. I assume that this means that the top speed of the Elco at some 41 knots could only be sustained for a relatively short period of time.

Category:

Autos & Vehicles

Tags:

• Packard
• V12
• PT Patrol Boat
• patrol torpedo boat
• WW2
• WWII
• Allison V12
• Liberty V12
• Packard V12
• pulling tractor
• sanddigger
• hot rod
• rat rod
• Packard Marine
• Marine V12
• PT Boat
• PT-109
• PT109
• tractor pull

[boozer95]

where in ohio are you located?

i live in the toledo/ bowling green area

[BackyardTechnology]

@boozer95

The tractor (not mine) is in West Salem, Ohio at a Xmas Tree Farm. Also near the famous Dragway 42.

[jkinemond]

Does any one know who owns this ? I would love to see it run We had one in a pulling tractor in 1977.

[BackyardTechnology]

@jkinemond

They live in Rural Ohio. He takes it around the country and does tractor pulls, so keep an eye out for it. It is just his hobby. They run a Xmas Tree Farm full time. EVERYONE wants to buy his spare engine, and he is not selling and does not want to be an internet celebrity. Who in their right mind does?

[Superpickle1st22nd]

I cannot believe this engine is being totally wasted in some REDNECK Tractor toy..

[BackyardTechnology]

@Superpickle1st22nd

Not wasted, preserved. As mentioned elsewhere, most of these engines are laying on the bottom of the Pacific when they sunk them when no more could be sold as surplus. Any survivors were bought from government auctions in the 1940's and 1950's. All others were sunk for Navy and Air Force target practice. Even worse, hundreds of surplus US war prize U-Boats were sunk in the Caribbean. Every major city would love to have one on exhibit. Now only Chicago has one (U-505).

[Mrnumbnut]

How can it be wasted when it's being used , seen and enjoyed ? What would Superpickle do with it ?

[amyjogonzalez]

My grandfather built these engines. He was very proud of his work. I think he would have approved of this. It's neat to see one running! Thanks for posting. 

[BackyardTechnology]

@Polybun

Sorry, as mentioned before, the loudness of the unmuffled engine overwhelmed the small mic on the digital camera. This ain't your local news crew!

[raginroadrunner]

@divisioneight ..at full throttle under way in an attack on an enemy vessel at full throttle... three of these engines would burn over 400 gallons of gasoline in an hour....and our stupid, incompetent dum assed military commanders sunk most of them off the coast of the Phillipines..we the people want our money back...who the hell gave them the right to do this???...their families should be sued down to their naked asses for theft of taxpayers money and equipment...what a bunch of dammed idiots.

[Polybun]

shit audio

[divisioneight]

The old WW-2 Elco PT boats had three of these beasts below decks. How I wish someone captured the sound of those old engines winding up to 40 plus knots. Too bad the Navy scrapped the "mosquito" fleet immediately after the war. They were great boats.