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Old 02-22-2013, 05:17 PM   #1
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Winnebago Owners Club
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Cat 3126 vs Cat C-7 HP and torque

My dad has a Cat 3126 in his 2003 Triple E Signature. I have a Cat C-7 in my 2005 Journey 39K. His is 300hp and mine is 350hp. From all the information I have been able to find, we both have the same torque: 860 ft/lbs. So now for my question: What does the extra 50hp do?? Is my engine more powerful than his or does the difference in horsepower really not mean anything?

2008 Newmar Dutchstar 4023, 425hp Cummins ISL
SOLD: 2005 Winnebago Journey 39K, 350HP C-7 Cat
Toad: Flat deck car trailer hauling a 1932 ford tudor sedan
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Old 02-22-2013, 05:28 PM   #2
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Deucenut, The easiest way to find out would be to race your Dad up a nice long hill. May the best man win. Seriously other than a few mechanical changes they're both the same. I believe the 3126 can be programed for the extra horsepower, but it won't make that much difference.


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Old 02-22-2013, 06:23 PM   #3
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Location: Spokane Valley, Wa
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If both vehicles were identical and the only difference was the Hp of the engine
the 350 hp engine would have a very small advantage in getting to speed first.
The 300 hp engine can get better fuel mileage but that depends on how it is driven.
The difference in the two engine has more to do with trying to meet the EPA rule
changes than anything else.
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Old 03-01-2013, 01:14 AM   #4
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The C7 is a later engine, there are some internal differences in parts. If I remember correctly the C7 is a cylinder liner engine where the early 3126 was not equipped with liners. The extra horsepower requires more fuel to accomplish it will give you a slight advantage in off the line full throttle acceleration at the cost of fuel. Everything equal and they both will pull a hill the same. Of course where it really makes a difference is on paper, that is where it counts!
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Old 03-01-2013, 04:46 AM   #5
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Glenn, just a clarification.... neither has cylinder liners - both are "parent bore" blocks. I've helped replace 2 C-7s (2005 and 2007)and 1 3126 (2000)
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Old 03-01-2013, 10:08 AM   #6
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So if I understand everyone correctly, there's nothing different really expect I'll be slightly quicker off the line and get worse gas mileage.....good to know

2008 Newmar Dutchstar 4023, 425hp Cummins ISL
SOLD: 2005 Winnebago Journey 39K, 350HP C-7 Cat
Toad: Flat deck car trailer hauling a 1932 ford tudor sedan
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