Rawze.com: Rawze's ISX Technical Discussion and more
CM871 400HP Dyno sheet - Printable Version

+- Rawze.com: Rawze's ISX Technical Discussion and more (http://rawze.com/forums)
+-- Forum: Big Truck Technical Discussion... (/forumdisplay.php?fid=1)
+--- Forum: Ask Your question... (/forumdisplay.php?fid=45)
+--- Thread: CM871 400HP Dyno sheet (/showthread.php?tid=1796)

Pages: 1 2


CM871 400HP Dyno sheet - Vjex - 06-01-2017

Hello All,
I'm looking to purchase a used 2010 truck with Cummins Isx 400 hp with 13 speed and 3.58 axle ratio.Truck has 700000 miles.I believe it used to be Knight's Trans truck and tranny has been converted from 9 speed.It runs fine, but if you remove oil filler cap,some smoke is to be seen at idle.Is this dyno sheet legit? 348 at wheels looks good, but 15" blowby concerns me, not to mention torque number (2310 lb-ft) which I think is total bs.This sheet was provided to me by seller. Also, you can see high coolant temperature of 208, and dyno setpoint is at 65.00 - no clue on that. Any input will be greatly appreciated! Thanks!


RE: CM871 400HP Dyno sheet - Vjex - 06-01-2017

[attachment=2814]


RE: CM871 400HP Dyno sheet - Waterloo - 06-01-2017

15" sounds excessive. Check out Rawze's video on blow by. https://www.youtube.com/watch?v=-Og4jCM6Rfg

I wonder what the service interval was on this truck, 30,000 miles?


RE: CM871 400HP Dyno sheet - Rawze - 06-02-2017

(06-01-2017 )Vjex Wrote:  Hello All,
I'm looking to purchase a used 2010 truck with Cummins Isx 400 hp with 13 speed and 3.58 axle ratio.Truck has 700000 miles.I believe it used to be Knight's Trans truck and tranny has been converted from 9 speed.It runs fine, but if you remove oil filler cap,some smoke is to be seen at idle.Is this dyno sheet legit? 348 at wheels looks good, but 15" blowby concerns me, not to mention torque number (2310 lb-ft) which I think is total bs.This sheet was provided to me by seller. Also, you can see high coolant temperature of 208, and dyno setpoint is at 65.00 - no clue on that. Any input will be greatly appreciated! Thanks!

A dyno report will only tell you one thing... Will it pull a trailer up onto the highway,.. and NOTHING MORE!!!

I can determine that by driving it and riding the brakes.

Check the overhead cams. check the engine and suspension and truck out,.. ignore the paint job or the clean interior as it is only done for the idiots to gawk at.

Plan on doing some serious work to it before putting it onto the roads like de-mandating it or having the entire EGR system and all the sensors and egr valve replaced. That you can count on for sure.

Plan on doing 3 oil changes at 5,000 mile intervals to break loose and get rid of the 700,000 miles worth of soot buildup in it.

The list only gets longer form here. -- Anything less and you are only lying to yourself.


RE: CM871 400HP Dyno sheet - Vjex - 06-02-2017

(06-01-2017 )Waterloo Wrote:  15" sounds excessive. Check out Rawze's video on blow by. https://www.youtube.com/watch?v=-Og4jCM6Rfg

I wonder what the service interval was on this truck, 30,000 miles?

Of course there is no service records available , but 30k + is a good bet :oh:


RE: CM871 400HP Dyno sheet - Vjex - 06-02-2017

(06-02-2017 )Rawze Wrote:  
(06-01-2017 )Vjex Wrote:  Hello All,
I'm looking to purchase a used 2010 truck with Cummins Isx 400 hp with 13 speed and 3.58 axle ratio.Truck has 700000 miles.I believe it used to be Knight's Trans truck and tranny has been converted from 9 speed.It runs fine, but if you remove oil filler cap,some smoke is to be seen at idle.Is this dyno sheet legit? 348 at wheels looks good, but 15" blowby concerns me, not to mention torque number (2310 lb-ft) which I think is total bs.This sheet was provided to me by seller. Also, you can see high coolant temperature of 208, and dyno setpoint is at 65.00 - no clue on that. Any input will be greatly appreciated! Thanks!

A dyno report will only tell you one thing... Will it pull a trailer up onto the highway,.. and NOTHING MORE!!!

I can determine that by driving it and riding the brakes.

Check the overhead cams. check the engine and suspension and truck out,.. ignore the paint job or the clean interior as it is only done for the idiots to gawk at.

Plan on doing some serious work to it before putting it onto the roads like de-mandating it or having the entire EGR system and all the sensors and egr valve replaced. That you can count on for sure.

Plan on doing 3 oil changes at 5,000 mile intervals to break loose and get rid of the 700,000 miles worth of soot buildup in it.

The list only gets longer form here. -- Anything less and you are only lying to yourself.

Thanks for your input!
I know that this truck is a long way from being put on service.I'm trying to understand if blowby of 15" means that there is not much of life left in engine.According to cummins, blowby is acceptable from 12" to 18". Anything over- calls for overhaul.I noticed on a truck a small oil leak where engine brake harness enters valvetrain,which only confirms blowby with some smoke trough filler tube.Will it reduce press having updated crankcase filter installed?


I cannot afford a decent truck right now, so my plan is to find one with some life left in it, do a complete egr tune-up and after 2 years or so (if lucky) to have it overhauled and de-mandated. With that much of blowby starting with, can it be reduced and somewhat controlled without having to tear up the engine?

Thanks in advance!


RE: CM871 400HP Dyno sheet - Rawze - 06-03-2017

(06-02-2017 )Vjex Wrote:  ...


I cannot afford a decent truck right now, so my plan is to find one with some life left in it, do a complete egr tune-up and after 2 years or so (if lucky) to have it overhauled and de-mandated. With that much of blowby starting with, can it be reduced and somewhat controlled without having to tear up the engine?

Thanks in advance!

I hear that story over and over and over and over --- IT NEVER WORKS OUT!!!!!

You can't expect to buy something that is at the end of its service life and "wish it" a new one!. Expect to inframe it soon,.. very soon after buying it and if you can't afford that -0-- GO FINANCE SOMETHING NEWER!!!


You Don't buy a "FIXER-UPPER" truck (or house or boat or even a lawn-mower) if you can't afford to "FIX IT UP!". =-- Bad business decision!!!

Get your personal finances in order FIRST -- Tell the old lady to stop spending all you damn money -- GO GET A COMPANY DRIVER JOB IF NEED BE AND SAVE SOME DOE!!!! --- Your going to need it.

I can't tell you how many people I have met who want to/or have just become truck owners that have their head in the clouds,.. when they should be focusing on putting their feet on solid ground instead. -- THEY ALWAYS LOOSE THAT GAME of buying something worn to the bone in the "hopes" of not having any problems for a couple years,.. -- IT NEVER WORKS OUT -- and to top it off --- THEIR FINANCIAL SITUATION DOES NOT IMPROVE ONE DAMN BIT -- because they are chasing problems and downtime the whole time they own the truck,.. then one day -- BOOM-- inframe time and they ain't got 2 cents to put towards it...;-- FIX YOUR FINANCIAL SITUATION!!!!! -- PRIORITY ABOVE ALL -- and if you can't do that --DON'T BOTHER OWNING A TRUCK!!!


RE: CM871 400HP Dyno sheet - Brock - 06-03-2017

I've been told by a couple places with dynos that thiers wasn't set up to calculate actual torque and to ignore it, they say the dyno cost 2x as much or more to buy if you want it to do so. Maybe that's the case here.

Personal experience, every single time I buy a miles out motor..... it blows soon! Whoever sold that hunk of crap did it for a reason.

There is a million trucks out there, youll thank yourself later if you take the time to find one with a strong engine.


RE: CM871 400HP Dyno sheet - Hammerhead - 06-03-2017

(06-03-2017 )Rawze Wrote:  I hear that story over and over and over and over --- IT NEVER WORKS OUT!!!!!

You can't expect to buy something that is at the end of its service life and "wish it" a new one!. Expect to inframe it soon,.. very soon after buying it and if you can't afford that -0-- GO FINANCE SOMETHING NEWER!!!


You Don't buy a "FIXER-UPPER" truck (or house or boat or even a lawn-mower) if you can't afford to "FIX IT UP!". =-- Bad business decision!!!

Get your personal finances in order FIRST -- Tell the old lady to stop spending all you damn money -- GO GET A COMPANY DRIVER JOB IF NEED BE AND SAVE SOME DOE!!!! --- Your going to need it.

I can't tell you how many people I have met who want to/or have just become truck owners that have their head in the clouds,.. when they should be focusing on putting their feet on solid ground instead. -- THEY ALWAYS LOOSE THAT GAME of buying something worn to the bone in the "hopes" of not having any problems for a couple years,.. -- IT NEVER WORKS OUT -- and to top it off --- THEIR FINANCIAL SITUATION DOES NOT IMPROVE ONE DAMN BIT -- because they are chasing problems and downtime the whole time they own the truck,.. then one day -- BOOM-- inframe time and they ain't got 2 cents to put towards it...;-- FIX YOUR FINANCIAL SITUATION!!!!! -- PRIORITY ABOVE ALL -- and if you can't do that --DON'T BOTHER OWNING A TRUCK!!!

I'll add one thing to the "fixer-up-truck" or "limp-it-til-I-can-afford-to-fix-it-truck", if YOU are not mechanically inclined enough or don't have the tools, you are in NO POSITION to purchase said type of truck.
Labor rates, parts costs, and the complexity of the electronic controls systems on these modern engines makes truck ownership considerably more difficult today than it used to be even 10yrs ago. The longevity is just not there anymore unless you know how to properly prepare and maintain one yourself.
I have owned trucks for over 20yrs, and I will honestly tell you it was far less stressful when I bought my first (5)y/o used truck with ~550k miles on it than the one that I currently own. Doesn't sound like much, but consider this; this truck is PAID FOR, I have owned it since new, and I have an emergency fund that can REPLACE the truck, not rebuild it I mean pay cash for another similar unit. The reliability issues I had before I found this site and properly "fixed" my truck still have my spidey-senses tingling fear every single day.
I actually recommend against most people becoming an Owner/Operator anymore. Between increasing EPA restrictions, modern HOS lack of flexibility, ever increasing regulations and enforcement, and drivers now actually being charged criminally for accidents if someone can be found negligent. I am honestly of the opinion that the risk is no longer worth the reward, unless you are very financially responsible, and have a solid financial foundation so you don't have the financial pressure to take the risks we all used to take years ago. Think about this; with e-log implementation, think about the reduced revenue from a virtual elimination of HOS fines, do you really think the DOT is just going to close up shop and lay off all those union secure jobs? Really? Or perhaps they now will have a different mandate to continue generating those fine revenues by finding something else to concentrate on? How much more strict do you think they are going to inspect and enforce defects on our vehicles? You are asking to become the owner of said vehicle...that means YOU will have to become even MORE vigilant about your truck...that will not happen without added expense. Still want a target, I mean "fixer-upper"?

I just unloaded at the Port of Baltimore. There was a reload there, but the rate was just too cheap to make any money on it running legally. I kid you not, 15yrs ago I'd have loaded it without a seconds hesitation, lied on my permit application and snuck out at night without pilot cars and such and I'd have made money on it. Nowadays? No F##ing way! Get into an accident like that, 15yrs ago, a fine and carry on, today, bracelets and go to jail! No $h!t, I was leaning against the very S/N unit I was offered while they were lifting my load off, I drove away empty.
If you cannot afford to think and operate with this mentality, you have no business owning a truck. Harsh truth, but it's a fact.