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Nilao · 08-07-2017, **(Subject: Increasing HorsePower -- What You Need To Know )**

I agree with rawze. Mine is set to 485 and if I get into it I can outpull most trucks up the hills. That's with a 10 speed and 3.58 gears. I get overrun on the flats cause I set my cruise at 60 but even at 20 psi boost I can still out pull these newer trucks on inclines that are spec'ed with 2.90 gears that my company specs for their lease drivers. They're the ones that complain they can't make any money but when you tell them to slow down they get upset that they have to make miles to be profitable. Those are the ones I call wanna be o/o that are still trying to make money by driving like a company driver thinking it's all about miles. It is not, the biggest factor in our business is fuel so if you want a raise, slow down and give yourself one.

adam1215 · 08-07-2017, **(Subject: Increasing HorsePower -- What You Need To Know )**

(08-07-2017 )Rawze Wrote:
(08-07-2017 )adam1215 Wrote: If I manage to turn this engine up will it be worth it? The problem I have is as soon as I start pulling hills with a load on (53,000lbs) usually I just get my a** handed to me with lack of power and fuel economy I go from the mid 7's to mid 5's. Will turning it up make that big of a difference? Will it help with fuel economy in the hills? Will break anything? The truck has 815,000 miles on it now. It has had the cams redone at 600,000 and rod and main bearings done around 30,000 miles ago a new turbo and the overhead has been every 150,000 miles since 305,000 miles

Maybe you should be looking at rear ratio instead?. Are you geared tall?. Mine is set at 450hp does just fine at 80,000 lbs and 3.55 rears on a 10 speed. I want longevity, not glory in how fast I get up a steep incline. No money in that. I'll take money over ego any day of the week.

I've thought about rear ratio too. I have 3:55 with a 13 speed someone I know suggested going to a 2:79 but I think that is too high of a ratio. I only run between 58 and 62 mph. I was just wondering if increasing horsepower and torque would have any great benefit or not. I will probably just leave it alone for now

Hammerhead · 08-07-2017, **(Subject: Increasing HorsePower -- What You Need To Know )**

(08-07-2017 )adam1215 Wrote: I've thought about rear ratio too. I have 3:55 with a 13 speed someone I know suggested going to a 2:79 but I think that is too high of a ratio. I only run between 58 and 62 mph. I was just wondering if increasing horsepower and torque would have any great benefit or not. I will probably just leave it alone for now

Anybody advising someone else complaining of "power/pulling" deficiencies to go to a higher ratio rearend is an uneducated idiot.
I don't know what sized tires you run, but I'd advise 3.70 for 22.5's or 3.90's for 24.5's...but that is completely generic. I would need to know; tire size, GVW, typical speed travelled, etc. for a proper recommendation. 3:55's with a 0.73:1 13th gear OD is what I would classify a "fast truck", not an advisable spec for a fuel conciensious operator.

For a comprehensive explanation of rearend ratios and amplification force see Post #19 of this thread http://rawze.com/forums/showthread.php?tid=1992&page=3

Hetdiesel · 08-11-2017, **(Subject: Increasing HorsePower -- What You Need To Know )**

I have a question on this I have 2 cm2250s one rated at 485 hp and one at 600hp. Visually looking at the engines look identical. Timing for the cams is 46 on the 485 and 66 on the 600 that's the only difference I seen. so what are the different components in these 2 engines cams, injectors, cranks? I'd like to know how different they really are?

Rawze · 08-12-2017, **(Subject: Increasing HorsePower -- What You Need To Know )**

(08-11-2017 )Hetdiesel Wrote: I have a question on this I have 2 cm2250s one rated at 485 hp and one at 600hp. Visually looking at the engines look identical. Timing for the cams is 46 on the 485 and 66 on the 600 that's the only difference I seen. so what are the different components in these 2 engines cams, injectors, cranks? I'd like to know how different they really are?

The 600 is a different tier with different injectors and a few other parts. Go register your engines on quickserv.com and look up some of the hard parts.

Hammerhead · 08-12-2017, **(Subject: Increasing HorsePower -- What You Need To Know )**

(08-11-2017 )Hetdiesel Wrote: I have a question on this I have 2 cm2250s one rated at 485 hp and one at 600hp. Visually looking at the engines look identical. Timing for the cams is 46 on the 485 and 66 on the 600 that's the only difference I seen. so what are the different components in these 2 engines cams, injectors, cranks? I'd like to know how different they really are?

(08-12-2017 )Rawze Wrote: The 600 is a different tier with different injectors and a few other parts. Go register your engines on quickserv.com and look up some of the hard parts.

Something seems OFF on this to me Rawze...the 2250 is a single cam engine, why does it have two digits denoting cam timing? Any of the datwplates I've looked at on 2250's only have a single digit.

The cam timing isn't what you're looking for to distinguish differences between engines, the CPL is what you compare. CPL is Critical Parts List, and it's code tells what Pistons, injectors, turbo, cams etc. were installed during build at the engine plant.

Rawze · 08-12-2017, **(Subject: Increasing HorsePower -- What You Need To Know )**

(08-12-2017 )Hammerhead Wrote:
(08-11-2017 )Hetdiesel Wrote: I have a question on this I have 2 cm2250s one rated at 485 hp and one at 600hp. Visually looking at the engines look identical. Timing for the cams is 46 on the 485 and 66 on the 600 that's the only difference I seen. so what are the different components in these 2 engines cams, injectors, cranks? I'd like to know how different they really are?

(08-12-2017 )Rawze Wrote: The 600 is a different tier with different injectors and a few other parts. Go register your engines on quickserv.com and look up some of the hard parts.

Something seems OFF on this to me Rawze...the 2250 is a single cam engine, why does it have two digits denoting cam timing? Any of the datwplates I've looked at on 2250's only have a single digit.

The cam timing isn't what you're looking for to distinguish differences between engines, the CPL is what you compare. CPL is Critical Parts List, and it's code tells what Pistons, injectors, turbo, cams etc. were installed during build at the engine plant.

That is 100% true. I just didn't want to pick apart the guys post, and figured he meant to say he was comparing 2 CM870's or some other pre- common rail engines. I don't even think I have ever seen "66" timing codes for any Cm871 either.

Just like you pointed out, no common rail has a stamp on it for injector timing, I.E. the CM2250 or CM2350 engines. They would only have a one number timing code for the wedge for the valve cam. I have however seen a few Cm870's with 66 on the cover for the wedges but it's uncommon. They are early models where they were playing with mechanical timing to make them meet emissions. Those same engines that did not have the proverbial "46" timing codes also take specific programming to go along with them too. it is not just a matter of hp settings on them, and you can't even change to a different program within the same cpl range on some of them without some minor ill effects unless that particular program also had proper corrections for the different static timing. It is difficult to find compatible programs because of this, and changes based on individual engine ser# as well.

if the person registers the 2 engine ser#'s on quickserv, they will get a better picture of what is different between them than any comments I can make without knowing them myself. With the ser#'s and quickserv, they can see the correct model engine they are and the correct timing codes too.

Hetdiesel · 08-12-2017, **(Subject: Increasing HorsePower -- What You Need To Know )**

You guys are right my bad I was wrong timing code is 06 on the 600 and they are 2250s both serial numbers are 79573063 is the 600 and the 485 is 79426214 don't have timing code on this one I'm not 100% sure now. bother are common rail so only one cam vs the 871s that the codes are 46 but I'm sure I've seen 66 somewhere or am I crazy?

Hammerhead · 08-13-2017, **(Subject: Increasing HorsePower -- What You Need To Know )**

(08-12-2017 )Hetdiesel Wrote: You guys are right my bad I was wrong timing code is 06 on the 600 and they are 2250s both serial numbers are 79573063 is the 600 and the 485 is 79426214 don't have timing code on this one I'm not 100% sure now. bother are common rail so only one cam vs the 871s that the codes are 46 but I'm sure I've seen 66 somewhere or am I crazy?

Yes, the common rail injector system is a single cam engine. The XPI fuel pump delivers the fuel pressure to the injectors.
On the dual cam engines, the left cam drives the injector and mechanically creates the pressure required to inject the fuel.
An 0/6 or even /6 timing code is the valve cam, which is a 6 degree timing wedge used to statically time the valve cam.
I have only ever seen one 6/6 timing code, and it was also as Rawze stated on an 870. I've never seen an 871 with anything other than a 4/6 timing code.

I was also not tying to pick your post apart. When someone is talking power, timing, tuning, and then there are timing codes that don't match engine families, my peabrain screams "STOP! Don't put the wrong information into the right ECM."