Author Topic: CAT C13 - why the large range in HP?  (Read 1784 times)

0 Members and 1 Guest are viewing this topic.

Offline CountryB

  • Newbie
  • *
  • Posts: 6
CAT C13 - why the large range in HP?
« on: October 12, 2017, 05:44:12 AM »
I have a C13 525 HP in my 2005 Beaver Patriot Thunder.

Looking at the specs for the C13 engine, there are several HP variations available - starting with 335HP going up to 525.

Why the large range? Is there a reason to have a smaller HP C13 over the larger size? Maybe better fuel economy.
I would think the more HP/Torque the better, you just wouldn't need to be a WOT as much on a lighter RV with the high HP engine as you would with a heavier RV.

How are these engines modified for the different HPs? Is it all done in the ECM or do they use different Fuel Injectors or Turbos or something else to boost the power?

Offline Brett Wolfe

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 2509
Re: CAT C13 - why the large range in HP?
« Reply #1 on: October 12, 2017, 06:14:09 AM »
You have properly identified the important variables.

As with most mechanical devices, the closer to the limit/the more that is demanded of them, the shorter their life.

This is less critical in an RV than an OTR truck with the same engine as the "duty cycle" is much more gentle when pushing 1/2 the weight.

And, as you mention, IF you use all the available HP, it will burn more fuel.

For more specific information on your engine, call the Caterpillar RV Hotline with your engine serial number.
Their number is 877 777-3126.

Offline Douglas Klink

  • Jr. Member
  • **
  • Posts: 71
Re: CAT C13 - why the large range in HP?
« Reply #2 on: October 12, 2017, 06:31:33 AM »
A c13 is top rated at 500 hp for otr truck use, the 525 is rv only.  Not sure what they did.  The tune that went in my ecm boosted torque significantly, mostly by changing injection timing.  I still have the variable valve timing (vvt) present and enabled in the software, the highest tune eliminates it.  As mentioned in another post, I do have to watch egt temp or it can get too high on long pulls, and I also have to watch coolant temp as I make more power now than the cooling system was designed for.  I'm sure it'll shorten the engine life, but I'm at 105,000 miles after ten years so I'm sure I'll still get another ten years out of it.  Mileage went up by about half a mile per gallon but more importantly out here in the west, my hill climb speed is up by 30% or more.

Offline CountryB

  • Newbie
  • *
  • Posts: 6
Re: CAT C13 - why the large range in HP?
« Reply #3 on: October 12, 2017, 08:09:04 AM »
Possibly the 525 hp was just done as just a selling feature (for those that focus more on the numbers).

Would I be better off to have the engine derated to 505 (or less) to improve engine life?

Offline Brett Wolfe

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 2509
Re: CAT C13 - why the large range in HP?
« Reply #4 on: October 12, 2017, 10:47:33 AM »
With the very small percent of time you are demanding maximum output combined with the million mile average engine life I would not be concerned.

The only engine I am aware of that has experienced mechanical issues based on higher (factory rated) output is the Cummins ISX.  In the highest HP ratings/RV ratings, dropped valves has been an issue.