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Project 350HP update

As I understand it guys, the optic bump is more to compensate for the developed slack (over time) in the timing chain than anything... people who have done this and then changed out the chain or put in gears had to undo it to get things running right again.

The optic bump was big news there for a while when quantum mechanic was bantering about on it, but too many really solid 6.5 guys have felt it unwise for me to get too intrigued by it.

I feel the need to emphasize the 'can be dangerous' part of this... JMHO.
 
I think we will keep the IP the way it is, no sense in messing with something that works perfect the way it is. Plus if I can get this programmer shootoff thing to go through, I would want the pump being factory so the results are not unfair to anyone. If 635 wants to do it after all my work is done then that will be up to him.
 
6.5quest said:
I think we will keep the IP the way it is, no sense in messing with something that works perfect the way it is. Plus if I can get this programmer shootoff thing to go through, I would want the pump being factory so the results are not unfair to anyone. If 635 wants to do it after all my work is done then that will be up to him.
Click to expand...

This is something to keep in your bag of tricks when while on the dino it hits 345 hp then maybe a bump to put you over the top. :D
 
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I have read on many threads that the APP pedal becomes so overly sensitive that it is tough to drive on slow/rocky roads... If Slim can manage it with a stick, then I don't see it being impossible.

It would also add a lot of extra strain to the drivetrain and/or camshaft I would think.

Also from what I have gathered it DOES NOT increase maximum output of the IP.

One question though, why does it not raise idle speeds considerably?
 
Just read through the thread.

Looks absolutely marvelous. Great clean and neat installation.

All the goodies are very impressive.

My main concern after scattering a few of these beasts is the platform itself.

The 6.2 Red blocks were not bad but still had issues with the main webs cracking.

The nodular iron cranks are also a big worry too. A forged crank in a late 6.5 block would have been sweet.

The rods are plenty good in these for gobs of power and the pistons will take it as well.

This little creature is going to put out some impressive power for sure.

Will be very interesting to see what it's capable of on the dyno.

Very best congrats on such a fine looking job.

Keep up the great work.

Missy
 
Matt Bachand said:
I have read on many threads that the APP pedal becomes so overly sensitive that it is tough to drive on slow/rocky roads... If Slim can manage it with a stick, then I don't see it being impossible.

It would also add a lot of extra strain to the drivetrain and/or camshaft I would think.

Also from what I have gathered it DOES NOT increase maximum output of the IP.

One question though, why does it not raise idle speeds considerably?
Click to expand...

You are right it does not give you any MORE total fuel, The only thing you get is more fuel than the program is calling for. And timing is slightly greater than the called for number.

I DO NOT recommend the Optic Bump, it can give you some serious problems and drive ability issues, Best left well enough alone. :D. The pedal can get very very sensitive and cause trailer hitching with the cruise. and bumpy roads can be a challenge to drive on smoothly.
 
Matt Bachand said:
Why does it not increase idle speed significantly Slim?
Click to expand...


Idle speed is controlled by the pcm with fuel metering. It can hold an idle speed with an optic bump, The problem arises when the pcm cannot meter fuel well enough to give you a smooth idle, The pcm watches the crank sensor and meters fuel to keep a smooth idle based on the on off time the pcm sees from the crank sensor. The pcm meters dwell time to each injector at idle to keep the crank pulses from the crank shaft positioning sensor at or very close to the same on off time.

This gives us our smooth idle even when we get 150 to 200 thousand miles on the motor, or worn injectors. Off idle this does not happen.
 
Yes idle is controlled by PCM period, when my new IP was jacked up loose Optic sensor screw, I was maintaining idle with only 2mm^3/1000 fuel smoked like a freight train with bad injectors on a hill pull, just backing up running 70mph with 11mm fuel, PCM monitors rpm and adjusts fuel solenoid accordingly.
 
So between this project and the possible PCM shootout I got my hands full. I am still waiting for the weather to give me a chance to get the truck done. I was able to get a little more done before it started raining on me. I really hope to have the truck up and running again by this weekend. I am just waiting on a few small parts to finish up the new fuel system. After that it is gauges, gauges, gauges!
 
Well, I need to think about how crank timing relates to cam, but I think you can get more power this way I did.

I have programmed my own program to advance to 22 degrees at 3300 RPM and 100% TPS and I tested it tonight and guess what I got 22 degrees timing at 3300 RPM at 100% TPS. So I have been running an idle desired timing of 5 degrees and hit 22 degrees no problem under hard acceleration or high speed.

So you dont actually have to advance the TDCO to get full travel of OS to max programmable position, you just have to put it in the programming to do it, and the stepper motor will make it so. I think some GM engineer was smoking some dope when they published a service bulletin saying turning the IP 1mm=2 degrees. This is why people can have retarded TDCOs, but the PCM program regulates timing based on that, so truck still runs great even with +1.5TDCO, because PCM made stepper motor put it to 8 degrees anyhow at idle, and stock programming only puts it up to 19 degrees max at high RPM.

You might get some more power just by having Kojo program you one to hit 25 degrees at 3600 RPM or so. This also means no reason to do optic bump when you can just advance it as much as you want at any time in the tuning. You can also program additional fuel at any time you want.

Here is my scanner snapshot, my speedo is at least 5mph slow at 80MPH when I checked with GPS unit. Next on the list is to see if we can just reprogram the way the program calculates desired fuel rate, so that we can just make the multiplier allow the max value to equal 100mm3 instead of 80. The reason it is 80mm3 now is that the multiplier in the program in 0.3125, and the max hex value is FF, which in decimal is 255, so 255 * 0.3125 is about 80. Although the APP lets you ask for more than 80mm3, and at 80mm3 the pulse width hasnt maxed out yet.
_________________________________________________________________
ENGINE SENSORS
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
Engine run time: 00:14:18
Boost pressure (MAP): 30.18 PSI
Desired EGR: 15.23 PSI
Desired idle: 806 RPM
EGR pressure: 14.72 PSI
EGR duty cycle: 0 %
Engine coolant temp: 191.9 F°
Engine speed: 3300 RPM
Glow plug relay feedback: 0 Volts
Glow plug voltage: 0.1 Volts
Ignition voltage: 13.1 Volts
Wastegate duty cycle: 20.3 %

_________________________________________________________________
INFORMATION SENSORS
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
PCM Calibration ID: 4835
Current DTCs: 1
Accel. ped. pos. 1: 3.67 Volts
Accel. ped. pos. 2: 1.39 Volts
Accel. ped. pos. 3: 2.24 Volts
Barometric pressure (BARO): 13.83 PSI
Battery voltage: 13.1 Volts
Fuel temperature: 98.2 F°
Intake air temp: 240.1 F°
Throttle position: 100 %
Turbo boost (Calculated): 16.35 PSI
Voltage reference sensor: 1.3 Volts

_________________________________________________________________
INJECTION PUMP SENSORS
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
Actual injection pump timing: 44.97 Deg °
Cam reference missed: 0 Counts
Crank reference missed: 0 Counts
Fuel calibration: 145 Counts
Fuel rate: 79.69 mm³
Fuel rate - Cruise: 0 mm³
Fuel rate - Idle: 0 mm³
Fuel rate - Maximum transient: 79.69 mm³
Fuel rate - Throttle requested: 95.62 mm³
Injection pulse width: 1.61 ms
Injection timing - Measured: 22 Deg °
Injection timing - Desired: 22 Deg °
TDC offset: -1.32 Deg °

_________________________________________________________________
TRANSMISSION SENSORS
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
3-2 PWM solenoid duty cycle: 0 %
Cruise target speed: 0 MPH
Cruise speed error: 0 MPH
Current gear of transmission: 4 Gear
Current torque signal pressure: 73 PSI
Current transmission ratio: 1:0.05 Ratio
TCC PWM solenoid duty cycle: 5.4 %
TCC slippage: 28 RPM
Transmission input speed: -3763 RPM
Transmission output speed: -3822 RPM
Transmission temperature: 178.7 F°
Turbine speed: 3322 RPM
Vehicle speed: 107 MPH
 
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Yep, I'm only talking about a PCM tuning change, no change to hardware. The timing is completely controlled by the PCM and as long as you are at least 3.5 degrees base timing (-0.5 TDCO) you can reach the max programmable timing advance of 25.5 degrees.
 
What ever arrives will be tried out. The engine will not be pushed to the limits other may want to see. It may do more if pushed farther but it won't be!
 
buddy said:
You might get some more power just by having Kojo program you one to hit 25 degrees at 3600 RPM or so. This also means no reason to do optic bump when you can just advance it as much as you want at any time in the tuning. You can also program additional fuel at any time you want.
Click to expand...

With my program you wont ever see 25 degrees advance, i dont want broke any pistons.. Optic bump makes more advance, but it also adds fuel.

buddy said:
Next on the list is to see if we can just reprogram the way the program calculates desired fuel rate, so that we can just make the multiplier allow the max value to equal 100mm3 instead of 80. The reason it is 80mm3 now is that the multiplier in the program in 0.3125, and the max hex value is FF, which in decimal is 255, so 255 * 0.3125 is about 80. Although the APP lets you ask for more than 80mm3, and at 80mm3 the pulse width hasnt maxed out yet.
Click to expand...

This is intresting part, there is formula how computer calculates pulse width, and it is what should be changed..
 
I mentioned all of what I am about to say in the PCM Shootout thread but wanted to say it again here. We will only be testing a few PCM's and blending the two articles into one. I promise you will not be disapointed in how it turns out and it will be available this winter and early spring in both MaxxTorque and Diesel World. Of course the articles will be slightly different and have differences in the pictures so having both will truly give you the complete story. Let me know if you have any questions.

Ian
 
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