Timing

[Lonestar10]

Couple questions

If a cam gear slips does it retard or advanced typically?

If you retard the engine should you build more boost?

Besides supposed power losses does retarding the engine hurt it? Since I know advancing creates more heat and can crack engine pistons.

All questions are in relation to SOI and injection cam

[Magard]

I wouldn’t think retarded injection timing would hurt. Egt will be high. Turbo boost from my playing around seems to go down with slightly retarded timing. Advanced timing creates water and oil temperature. Cooler egt. Slightly advanced timing seems to run really smooth but creates slightly higher water and oil temperature. Advanced timing gets smooth under slight power but violent feeling under power and pulling power seems to go down. When right the 2250 seems clunky or chuggy sounding but smooth in the gearshift. In a 2250 this can go one way or the other in a degree or less. Meaning you start really splitting hairs to get it right. 871 isn’t this sensitive but should still have similar characteristics. I would think a degree in soi one way or the other should be noticeable if it’s close to right.

[ynot]

Usually retarding the timing helps with turbo spool, itll affect upper boost a but not much though.

Advancing or retarding is just changing where your heat energy is used with retard the combustion gas dont hang around the cylinder as long an are pushed into the exhaust an the extra heat spools the turbo quicker leading too better power an higher egt's. With advancing the combustion happens sooner an the gas's stay in the cylinder longer giving a more complete burn for better mpg, but the heat energy from that better burn, instead of going out the exhaust for the turbo gets absorbed into the motor making for higher coolant/oil temps an lower egt's

Hope that makes sense

[Lonestar10]

Thanks for response. ive just been foolering around trying to adjust for my fubar 4.5wedge cam instead of the 4 it was suppose to be and also chasing other demons right and noticed as i went negative in SOI my boost came up higher in pulls but power did seem to go down. my EGTs stay around 600-625 on flats cruising and only go up to 700-725 on a long hard pull "sensor is after turbo in 7th injector pipe".

another thing is the difference in power between say 20-25lbs of boost and 35-38 seems negligible to me out of the several trucks ive driven and at 20lbs the lie o meter is already at 2.5mpg and doesnt drop any further the higher the boost goes.

500HP Paccar MX13, 2 450hp 13L MAXXForces, 1 450hp detroit 15L, 1 550HP 3406 CAT this truck/engine combo feels the slowest/gutless of them all

the 3406 CAT i pulled 100-110k lbs gross of grain and that truck would walk all over this one and still get 6.2MPG all day driving 70-75MPH where i drive 65-67 now.

so its pushing me more and more to go see the masters to find out whats wrong with her. i love the truck and the engine for me works for being able to work on it myself but im getting to a point where my skill level isnt enough to do her justice as all the parts ive replaced so far havent seemed to make a dent even though there have been issues with all that ive replaced.

[smorgan87]

If ur injector cam slipped it should retard injector time if im thinking right (engine kept going, cam didnnt so it should lose a degree or 15 but theres no telling where ur static time is at now and trying to compensate in soi tables or master soi is a shot in the dark because a cpl degrees in either direction can make a big difference. What gives u the idea it slipped? Is ur mm updated to the most recent version with the set soi tables? Egts snd prty normal maybe a few degrees cool on a hard pull but real close. Whats ur torque set at and where in the rpm range? Injectors good? Fueling actuators good?

[Lonestar10]

500 - 2000RPM and 1850 - 1200RPM

how to view my HP/TQ curves i havent the slightest.

i was told by someone that with an MM tune not fully customized a 500HP stock tune would outpull my overlayed.

pretty sure the big man updated my timing tables to the most current.

Overhaul was done by International in Mankato, MN before i purchased so lets just say i dont trust their work especialy after my truck was DOTed by them and the day i brought it home all sorts of DOT items were bad.


in last 6 or 7 mo all items in list replaced/maintained
oil changes every 13-15k
Davco changed whenever it needs it i keep 2 spare filters in truck at all times
2200 filter changed at oil changes
Air Compressor
Injectors
Actuators
Fuel Shut Off Valve
IMAP
Exh BPress
EGR Delta
Charge Air Cooler
Thermostat
Exhaust Manifold Gaskets
Cam and Crank Sensors
Oil Press Sensor
Charge air/pipe silicone boots and clamps
I did the MM work so cans are empty cept for 2" or so around the perimeter.
Rear Ends 3.36 to 3.70
Clutch adjusted/inspected
Air Dryer rebuit
tensioner pulley on main belt
and who knows im probably forgetting something.

been getting random Turbine temp 2346 codes every now and then so probably need to change IMAP/Exh BPress/Turbine suction temp sensors.


Some more questions

when i put a new program into the truck should a power loss 1117 code be popping up? also should CT or Insite stay connected and running entire time the program is on and connected to truck? ive been having issues might be 30min might be 5hrs where CT or Insite will lose connection with the truck with CT i just disconnect USB and Reconnect and it begins getting information again.

i always make sure to reboot computer and re attach usb before sending a program to reduce risk of bricking to the bare minimum.

[smorgan87]

No, u shouldnt get any codes just from downloading a file to ur ecm unless something is wrong with from the snds of it a sensor, the engine file itself corrupted or a bad command somewhere or the ecm is bad. I sent u a pm. Send me ur engine file when u have a minute and ill take a look at it. Anytime u disconnect the data connector from the truck always close the module in ctrm or disconnect from ecm in insite first.

[Waterloo]

You are probably due for a new ECM, I am now a believer, 800,000 miles is the lifespan. I cannot believe the new ECM made that much of a difference. Even though the old ECM said everything was fine... Well, apparently it was not. Identical programs, both installed personally by Rawze on both ECMs. That new ECM has already paid for itself in fuel savings alone, and it hasn't even been installed but for a few weeks.

[ynot]

I've had the power Los code on both my trucks after downloading a tune, after the download is done an it says successful turn the key off for 5-10secs an let the ecm reset then hit the ok button in Cpern an let it reconnect that always turns the code off for me. An once the codes are cleared they stay cleared.

The usb disconnecting again seems normal too me happens all the time especially driving down the road I think it's from the laptop bouncing away jostling the usb cable.

Your timing concerns are harder too nail down with out checking the injection timing too see why they used a 4.5 degree wedge which is used too advance injection, in quick serve in the service manual if you search wedge the first result explain how do do it. Finding someone with the tools is the problem