Hedgehog. Sounds kinda cute, doesn't it?

Well, if it's torque you're looking for, Cummins debuted its new "Hedgehog" at Goodwood last month, and "cute" is about the last thing you'd call it. Despite the diminutive moniker, this Hedgehog is a torque beast indeed. Providing some 11,800 ft-lbs of same, along with 4,000 horsepower, this engine sort of ups the ante on bragging rights for who's got the most powerful smoker motor in the parking lot.

Designed for service in mining dump trucks, railroad locomotives, and large stationery applications, sadly it won't be offered in next year's RAM, as there seems to be a packaging problem with an engine considerably larger than said pickup itself. Still, it's interesting to consider that the 95 liter, 12 cylinder engine displaces more volume per cylinder than the entire Cummins engine in this year's RAM pickup.


Hedgehog - by Cummins

Just in case the Hedgehog isn't quite large enough for your plan to conquer earth, it looks like Cummins is working on a 120-liter variant with 20 cylinders, 5,000 horsepower and an estimated 14,750 pound feet of torque. Anything larger is going to require a nuclear permit.

 

 

4,000 / 95 = 42 HP / L
11800 / 95 = 124 lb ft / L

those spec are really not impressive if you look at the per unit level.

 

holy moly, that motor is size of a house!

 

Got a chance to sneak a peak at a mere 47L Inline-6 turbodiesel from underneath the wheel well of a "small" mining truck at a local quarry when they had a public open house, and even that was pretty darned impressive. And you can't compare these heavy-duty off-highway monsters with light-duty on-highway engines. These beasts will make their rated power all day long uphill both ways. Sure light-duty passenger vehicle engines will make a ton of power (per liter), but "light-duty" means exactly that. They're not designed to make that power 25 hours per day 8 days per week like these things will, and if you try they won't last very long.

 

Impressive engine for sure. More power FTW!

 

While the "Hedgehog" is big as powerplants for wheeled vehicles go, it is dwarfed by the diesels regularly installed in our commercial oceangoing fleets. Wärtsilä-Sulzer manufactures the largest diesel engine in the world; with 25 of them plying the world's sea lanes and another 86 on order, business is good. Here are some of the engine's staggering specs:



Total engine weight 2300 tons (The crankshaft alone weighs 300 tons.)
Length 89 feet
Height 44 feet
Stroke/Cycle 2-stroke, turbocharged
Cylinders 14
Bore 37.79 inches
Stroke 98.42 inches
Maximum power 108,920 hp at 102 rpm
Maximum torque 5,608,312 lb/ft at 102rpm
Fuel Consumption 1660 gal/hr of heavy fuel oil (at "economy" power setting)

Strangely enough, in the world of fast supercontainer ships, that engine is as economical as it is powerful. Pushing the Emma Maersk, a 1300-ft container ship weighing over 170,000 tons to a cruising speed of over 31 mph. She regularly makes the Pacific crossing from Hong Kong to Long Beach in twelve days. Emma Maersk is also efficient in the use of manpower as well, with only a crew of 13 required to handle the massive vessel, thanks to computers and automated systems.

But how can that enormous engine be considered "economical"? Well there are economies of scale to be considered here. If you compare the efficiency of this diesel in terms of energy converted to thrust, it's far more efficient than automotive or aircraft engines. Where even an efficient automotive or aero engine converts about 25% to 30% of its fuel into motive power (the rest is wasted as heat), the RTA96-C is busily turning 50% of its fuel into motion. Remember too, the Emma Maersk and her sisters are hauling 11,000 standard 20-foot containers, so the breakdown of what it costs to move, say one 360 lb motorcycle from China to the US, is miniscule.

What about the engine speed rating at 102 RPM, isn't that pretty slow? Well yes and no. Considering the piston speed at 102 R's is just under a slow 28' per second, the sheer enormity of the metal masses being flung about at this rate is staggering.

For more information, specs, and some amazing assembly photos of the Wärtsilä-Sulzer RTA96-C, see:

http://www.emma-maersk.com/engine/Wa...er_RTA96-C.htm

 

Wow, if the hedgehog is a size of a house, that engine is a size of a building!