Many questions

[Mattman]

Can the Rev limiter be changed with just insite, believe I have the version they call pro??

Mine is at 1700 rpm, but not always. It will go part 1700 sometimes. If you Rev let off the throttle and rev again it won't go over 1700. Not sure what you call it, but would like it gone. Usually isn't a problem until you let off throttle and the you have to clutch to get it out of gear cause you let it hit 1700 and can't get it to rev higher.

[Rawze]

(04-25-2020 )Mattman Wrote:  Can the Rev limiter be changed with just insite, believe I have the version they call pro??

Mine is at 1700 rpm, but not always. It will go part 1700 sometimes. If you Rev let off the throttle and rev again it won't go over 1700. Not sure what you call it, but would like it gone. Usually isn't a problem until you let off throttle and the you have to clutch to get it out of gear cause you let it hit 1700 and can't get it to rev higher.

I changed his in insite to, I think, 2100. I also removed that gawd-aweful gear-down protection + set out-of-gear rev limit to 2100 as well I think.

(CM871)

[Chamberpains]

What model cummins do you have? My cm870 would only allow me to go to 1800 rpm max with insite. I had to use Calterm to shut of the limiter completely.

I hint at what you should look for here https://rawze.com/forums/showthread.php?...9#pid44949 if your working with a cm870

[amermextrucker]

My data plate says goverened at 1800 rpm does that mean I shouldnt go past that RPM ? Ive been driving it loaded at 1600 rpm. I hope this aint a dumb question.

[Rawze]

(04-25-2020 )amermextrucker Wrote:  My data plate says goverened at 1800 rpm does that mean I shouldnt go past that RPM ? Ive been driving it loaded at 1600 rpm. I hope this aint a dumb question.

mechanical structural max limit ( past red line) for the ISX is 2700 from what I have been told, however Cummins limits them, says 2400rpm max. Some programs hard-limit it to 2100 ... - Anything lower than 2100, and it is just your programming or adjustable settings in the ecm.

I sometimes drive mine for hours in the 1800+ range when in those dammnedd PA I-70 hills and heavy to help save fuel and keep momentum up. - Does not hurt a thing.

Pressing the fuel pedal more than about half way below 1400 rpm or so creates far more wear than anything you do above 1500. - What rpm range you should be using however for best efficiency is all a trade-off depending on load, needed power for maintaining momentum, etc.

[amermextrucker]

Rawze,

I drive @ 1450 MT. Would you consider that lugging it?

[Rawze]

(04-26-2020 )amermextrucker Wrote:  Rawze,

I drive @ 1450 MT. Would you consider that lugging it?

I don't like pushing mine at 1400-1450 for sustained periods much at all. I try to stay at 1500+ when I need power and below 1400 when barely on the pedal. This is because the ISX is known for having harmonics in the crank and bottom end in the 1400-1450 rpm range. It shows up prominently with bad custom tuning programs/bad-deletes or when the power is at 800HP+ and steps to mitigate it are not taken, so I know it is there, even though it is not likely an issue at all under normal power levels. - Some guys drive them there, I just choose to avoid it out of personal piece of mind/opinion only though. I personally consider the 1450 or so range at the point where you grab your next gear and bring the rpm back up when your foot has to be most the way to the floor to climb that hill.

just my own thoughts on it.

NOrmal power levels and decent programming ... not likely an actual issue... However i have seen plenty of times that had bad programming .. or bad programming and 700+ or 800+ horsepower, literally beat the crank bearings out from around the crankshaft at 1400-1450 rpm becasue of that harmonic on competition engines where a bunch of idiot tuning dips#$its tried to put the screws to them. here is what that looks like ...

(photo borrowed from elsewhere...)

[Aussie Steve]

(04-26-2020 )Rawze Wrote:  

(04-26-2020 )amermextrucker Wrote:  Rawze,

I drive @ 1450 MT. Would you consider that lugging it?

I don't like pushing mine at 1400-1450 for sustained periods much at all. I try to stay at 1500+ when I need power and below 1400 when barely on the pedal. This is because the ISX is known for having harmonics in the crank and bottom end in the 1400-1450 rpm range. It shows up prominently with bad custom tuning programs/bad-deletes or when the power is at 800HP+ and steps to mitigate it are not taken, so I know it is there, even though it is not likely an issue at all under normal power levels. - Some guys drive them there, I just choose to avoid it out of personal piece of mind/opinion only though. I personally consider the 1450 or so range at the point where you grab your next gear and bring the rpm back up when your foot has to be most the way to the floor to climb that hill.

just my own thoughts on it.

NOrmal power levels and decent programming ... not likely an actual issue... However i have seen plenty of times that had bad programming .. or bad programming and 700+ or 800+ horsepower, literally beat the crank bearings out from around the crankshaft at 1400-1450 rpm becasue of that harmonic on competition engines where a bunch of idiot tuning dips#$its tried to put the screws to them. here is what that looks like ...

(photo borrowed from elsewhere...)

Yep I would agree
I have a mixture of Cat, Cummins and Detroit, I don't care what colour the engine is. When your in a pull shift it before 1500 rpm and get the revs back up in the top of the rev band. Any of my drivers that are lazy with the gear stick don't last very long. I tell them I would rather they hit 2000 rpm at gear changes with three trailers on than lug them. It really suprises me that drivers cannot hear the engine protesting loudly when asked to make maximum torque in the 12 - 1400 rev range. And why do the manufactures allow the torque to be available in that rev range. I would personally like to limit the torque available below 1500.