Why do heavier trucks use Less HP....
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Joined: Mar 2008
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From: Paramount, Ca
We had a customer with a 5.9L cummings in a 26' delivery box truck. I thought it drove pretty good considering the size and weight of the truck. My boss repaired the block. He welded it in 3 spots, a few months later it cracked the block again in 2 other spots. We put a new block in and he had the pump turned down a little bit. He was talking about doing a 466 swap if it breaks again.
Posting Guru
Joined: Jan 2005
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From: Douglas, Georgia
I work on marine diesels and the rating is different still.
On this tug I'm now now, we have 16v149 Detroit diesels.
16 cylinders, V block, 149 cubes per cylinder.
and yet at 2000rpms we only make 900hp per cylinder? that is 2384 cubic inches per engine (we have two, 1800hp boat)
I used to be on another boat with EMD 16 645's. V16 645 cubes per cylinder.... it only made 1500hp.
yes, thats all, but they also last 30,000hours with minimal problems.... the occasional power pack, the occasional injector. On a tow, this engine may be making full power for 200-300hours straight without being shutdown.
Now a cummins 5.9 with heavy mods can make 900hp, or so I'm told (never seen on a dyno). I would love to see a 5.9 towing a barge vs a 16v149..... The cummins would be a puddle of steel before the Detroits scheduled oil change. I've only ever seen the cummins 5.9 to power a generator out here. The markings on the side claimed 115hp raw water cooled, 95hp keel cooled
On this tug I'm now now, we have 16v149 Detroit diesels.
16 cylinders, V block, 149 cubes per cylinder.
and yet at 2000rpms we only make 900hp per cylinder? that is 2384 cubic inches per engine (we have two, 1800hp boat)
I used to be on another boat with EMD 16 645's. V16 645 cubes per cylinder.... it only made 1500hp.
yes, thats all, but they also last 30,000hours with minimal problems.... the occasional power pack, the occasional injector. On a tow, this engine may be making full power for 200-300hours straight without being shutdown.
Now a cummins 5.9 with heavy mods can make 900hp, or so I'm told (never seen on a dyno). I would love to see a 5.9 towing a barge vs a 16v149..... The cummins would be a puddle of steel before the Detroits scheduled oil change. I've only ever seen the cummins 5.9 to power a generator out here. The markings on the side claimed 115hp raw water cooled, 95hp keel cooled
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The 5.9 Cummins is a grossly over rated engine. It isn't designed for high horsepower (sustained). You may get 900hp out of it but that is for what 1 minute or less.
The only reason why you see a 5.9 Cummins in a medium duty truck is when the truck was new the 5.9 was the cheapest engine option. It is the only reason why you see one in a medium duty. A gas engine actually does better in a medium duty over the 5.9.
The only reason why you see a 5.9 Cummins in a medium duty truck is when the truck was new the 5.9 was the cheapest engine option. It is the only reason why you see one in a medium duty. A gas engine actually does better in a medium duty over the 5.9.
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From: Isanti, MN
Very interesting post, DeepRoots
Not difficult to see how the last that long, though. 149 CI x 16 cylinders = 2384 CI...which converted into liters would be just greater than 39 liters.
So, 900HP/39 liters = 23 HP per liter. If a 6.0L PSD made that mush specific output, you'd be seeing somewhere around 138 gross HP. And it'd probably last longer than it's driver.
Just curious now, is that big marine engine turbocharged or N/A?
Not difficult to see how the last that long, though. 149 CI x 16 cylinders = 2384 CI...which converted into liters would be just greater than 39 liters.
So, 900HP/39 liters = 23 HP per liter. If a 6.0L PSD made that mush specific output, you'd be seeing somewhere around 138 gross HP. And it'd probably last longer than it's driver.
Just curious now, is that big marine engine turbocharged or N/A?
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