The Diesel Garage banner

1 - 8 of 8 Posts

·
truckn'
Joined
·
1,720 Posts
Discussion Starter #1
I just got to thinking about this

6.7 litre cummins-350 hp (suppost to be higher in coming years)

14 litre cummins isx-600hp

why doesnt cummins make like a 800hp factory engine in a semi? It has twice the displacement as its little brother but the little ones are slowly creeping up to and over the 400hp mark.
 

·
Senior Member
Joined
·
3,754 Posts
Its true torque is what really matters when pulling loads but to answer your question, it is all about EMISSIONS AND RELIABILITY. The big thing that is choking any engine big or small is emission garbage. If you put a Pittsburgh power box on a 14 liter it can make 800 horse, just by changing the engine parameters. Another reason they don't push the bigger motors and try to max them out. They set the power ratings more conservativly so that they can make that much power day in day out and still run a million miles without any trouble. If you run that 6.7 liter all day long pulling heavy loads day in day out and you are using all 385 horses day in day out you wont get reliability with it.
 

·
truckn'
Joined
·
1,720 Posts
Discussion Starter #4
i was thinking reliability also
 
Joined
·
88 Posts
Of course they do make big horsepower marine, emergency, and military engines. and i doubt that they are too unreliable. I really doubt that the majority of the drivers need
(or can control) that much horsepower. It's probably safer this way
 

·
Junior Member
Joined
·
281 Posts
15 litres has lots of power potential!!! As others have stated it takes parameters to make an easy and I mean easy 800 hp,seen a truck 5 years ago break the dyno at cummins,made 785 to the wheels but 2650 pd ft of torque in a 295 wb rig!:kick
 

·
Junior Member
Joined
·
3,533 Posts
Most engines now only get full torque and HP in the higher gears, the drives will not handle the multiplication, of torque, that they have now.
 

·
Fleet Owner
Joined
·
191 Posts
Last time i looked at a new truck, the biggest trans you could get is 2200ftlb. I think you will find that the driveline capacity is whats limiting the outputs....

Manufacturers have to warrant thier equipment, and until the driveline manufacturers catch up a little, they wont offer higher HP.

We have Volvo engines out here in Volvo's and Macks, about to be released within months at 700hp, and 2200ftlb, but you have to take thier transmission with an autoshift.

I guess it stops driveline abuse, leading to warranty issues.

:)
 
1 - 8 of 8 Posts
Top