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mystere900 · 07-06-2007, 10:00 AM

I was told by a Cat specialist at truck shop that my 300HP C7 could be bumped up to 350HP for a fee of around $1000. I'm assuming all that's necessary is some kind of software change to the computer. Does anyone have knowledge or direct experience with this up-grade?

mystere900 · 07-06-2007, 10:00 AM

I was told by a Cat specialist at truck shop that my 300HP C7 could be bumped up to 350HP for a fee of around $1000. I'm assuming all that's necessary is some kind of software change to the computer. Does anyone have knowledge or direct experience with this up-grade?

vicsryd · 07-06-2007, 02:41 PM

A 2004/2005 C7 should be upgradable simply with a software update (aka reflash). Most CAT dealers will do this for free if done the same time as a chassis PM.

I recommend you contact CAT support directly at 877-777-3126. You'll need your engine serial number.

mystere900 · 07-08-2007, 05:55 AM

Thanks Jon (or Vicki). Do you think there would be a noticeable change in performance? I assume because you never get something for nothing there would be an increase in fuel consumption. Next time I need scheduled maintenance I'll give it a try. Although, I'm skeptical that Cat would give anything away for free.

vicsryd · 07-08-2007, 06:35 PM

I believe you are already rated at 860 ft lbs of torque which is what gets you up the hills. An increase in horsepower would only show up in slightly improved acceleration at full throttle which is nice when you need it.

If it were me I'd get the flash updated for this and other "software imporovements". As far as mpg goes I find the Economy Mode setting on the Allison 3000Mh transmission not only lower the shift points but also reduces max turbo boost by a couple of psi which effectively derates the engine by 30 horsepower or so. To me this one way to control trading power for mpg.

It's in CAT's best interest to reflash the ECU's because some of the sofware updates help avoid problems down the road that might mean $$ in warranty claims.

mystere900 · 07-09-2007, 05:17 PM

You are correct, my C7 300 HP is rated at 860 ft. lbs. of torque at 1440 RPM as are the 330 and 350 HP engines. I doubt that many people travel the interstate at 1440 RPM or 50 MPH. If I am interpreting the HP/Torque/RPM graphs on the link below correctly, the increase of HP causes the torque to drop off less steeply as RPM increases. In terms of performance, I think this would give the coach better pulling capacity at higher speeds. The old saying, "Torque gets you going and HP keeps you going" seems to correspond with this. Yes, No?

https://ohe.cat.com/cda/files/378796/7/LEHT4483-08.pdf

mystere900 · 07-09-2007, 05:26 PM

I don't know why the link didn't work but if you copy and paste to the address bar it should work. If not go to the Cat web site about C7 RV engines and click on the link "C7 RV Diesel Engine with ACERT® Technology (EPA 07)"

GStream40 · 07-10-2007, 05:12 AM

Roger,

You are correct with your view as to the torque dropping off less steeply.

I had my CAT C7 increased from 330hp to 350hp at the CAT service center during a software upgrade and it was done at no charge by the tech.

Of course just moving up 20hp made very little difference that I could notice. But in your case of moving up 50hp it would be quite noticeable I would think since that would be a 16% increase.

Ron