Unique Question Concerning Injection Timing

cut7 said:
I have done substantial test on this pump, it's 0-12v to operate both the timing & fueling racks; the fueling rack has a feedback circuit which is 0-5v.
Click to expand...

Bosch ECM controls it 0-5 volts.

Did you test max fueling ? I never got answer from any pump shop, I know it makes at least 750 hp in generator engine and I think it is not even close to max in that application.
 
cut7 said:
Yes it makes sense. I see what you're saying, but I'm not sure I agree with you. Having said that, it's always good to consider dissenting opinions; especially from a fellow mechanical engineer. I guess a good place to start would be find out what max timing is on a performance common rail tune that does not make use of pilot injection. Anybody want to contribute that info?

BTW, the curve you've suggested is exactly what I plan to do. (Great minds think alike!) ;)
Click to expand...

Good deal. :Cheer: So the reason I'm confident that injection timing will play a role is because 13mm pumps use different timing based only on the fact that they have a ~17% larger bore and inject fuel much quicker because of this. Do you know the stroke, bore, and ramp of your pump? That might get you an idea as to where you want to start.

Have you gotten the pump flow tested to see how much fuel you'll have. That can give you a hint as well for timing.

As for common rail injection, I would assume they have a much quicker injection event than a 12mm pump at most rpm ranges.

cut7 said:
I am reading the RPM — & other several factors — from the CAN bus; which is getting it's RPM data from a 60-2 reluctor wheel on the damper, read by a 0-5v Hall-effect sensor. From there, my controller commands the timing & fueling racks; the timing based on a table. It also controls the waste gate of my compound turbos; but that's not relevant to this conversation.
Click to expand...

Have you done any testing on how fast it can actuate? I would assume there's some lag, so if you're using an Arduino to control this, look up smoothing functions. There's all sorts of free software out there for VGT control that would be very very similar to what you're doing.



All that stuff said, I really think you need to toss it on and just start playing with it. Timing is a funny thing and it seems to be +-2deg truck to truck to get the same outcome. $.02
 
Leiffi said:
Bosch ECM controls it 0-5 volts.

Did you test max fueling ? I never got answer from any pump shop, I know it makes at least 750 hp in generator engine and I think it is not even close to max in that application.
Click to expand...

I can tell you for an absolute surety that it take 10.08v to get the timing rack to move to its max position (13.5mm).
CorneliusRox said:
Good deal. :Cheer: So the reason I'm confident that injection timing will play a role is because 13mm pumps use different timing based only on the fact that they have a ~17% larger bore and inject fuel much quicker because of this. Do you know the stroke, bore, and ramp of your pump? That might get you an idea as to where you want to start.

Have you gotten the pump flow tested to see how much fuel you'll have. That can give you a hint as well for timing.
Click to expand...


Max fueling was tested on a Bosch bench (with a Bosch controller commanding it) discharging through .7mm injector nozzle (as per Bosch's specs). My maxed & balanced P-pump put out 398cc — which, BTW, corroborates what the bench operator told me. He said a 12mm P-pump can put out about 400cc max.

On the same bench, the same day, under the same conditions, my H-pump put out 687cc. Its peak injection pressure is about 150-200 bar higher than a P-pump, & its cam is a MUCH faster rate (meaning it reaches peak pressure much faster). It also has constant pressure valves that retain pressure in the line just below the pop pressure of the injector,;which reduces dribbling, & the haze associated with it.
 
Last edited:
cut7 said:
I can tell you for an absolute surety that it take 10.08v to get the timing rack to move to its max position (13.5mm).


Max fueling was tested on a Bosch bench (with a Bosch controller commanding it) discharging through .7mm injector nozzle (as per Bosch's specs). My maxed & balanced P-pump put out 398cc — which, BTW, corroborates what the bench operator told me. He said a 12mm P-pump can put out about 400cc max.

On the same bench, the same day, under the same conditions, my H-pump put out 687cc. Its peak injection pressure is about 150-200 bar higher than a P-pump, & its cam is a MUCH faster rate (meaning it reaches peak pressure much faster). It also has constant pressure valves that retain pressure in the line just below the pop pressure of the injector,;which reduces dribbling, & the haze associated with it.
Click to expand...

Ah, that's pretty cool! You should be all set on fueling then. Quick injection event, paired with some higher pop pressure injectors, and being able to change timing should make that thing ridiculously snappy!
 
CorneliusRox said:
Ah, that's pretty cool! You should be all set on fueling then. Quick injection event, paired with some higher pop pressure injectors, and being able to change timing should make that thing ridiculously snappy!
Click to expand...

All this, combined with my super snappy turbo setup should make for the ultimate street driving & towing .machine
 
Leiffi said:
Yes, you are right.
Click to expand...

I hope I didn't come across as a jack wagon, I just wanted to make sure we don't spread any misinformation about this pump. Lord knows, there's enough of that out there on the internet already!

I've had this pump for a few years and have done an enormous amount of research on it. At the risk of sounding a bit hubris, I probably know more about this pump than any ten people you'll run into.
 
There was a thread here CA 2012 that was running an H pump via arduino. I'm curious how that ended.

Sent from my XT1575 using Tapatalk
 
biggy238 said:
There was a thread here CA 2012 that was running an H pump via arduino. I'm curious how that ended.

Sent from my XT1575 using Tapatalk
Click to expand...

Find that post & put a ink to it here, please.

Was it Shadowtrooper? He never got it up & running.
 
cut7 said:
All this, combined with my super snappy turbo setup should make for the ultimate street driving & towing .machine
Click to expand...

Higher compression would be that much better too! I run a 200rpm lower stall in my 47re and then use thicker fluid to bring it down more, and have a lot of my tuning set up to make it very drive-able between 800rpm to 3300rpm.

biggy238 said:
There was a thread here CA 2012 that was running an H pump via arduino. I'm curious how that ended.
Click to expand...

Poor guy got his truck stolen... He had an arduino running a stock 6.0L turbo that was fully functioning, and then was using a smaller version of this pump I believe.
It was a 12V in a Chevy truck. Very custom build to make one super drive-able and reliable diesel.
I don't think I've seen him on in a long time since then. His name was ShadowTrooper I believe. I used to have his cell, maybe I'll see if he wants to hop on this.
 
Start injection at idle around 8° BTDC then ramp to ~32-36° BTDC depending on what your headgasket can hold. Your best cruise MPG will be somewhere between 14-18° BTDC.

You could get away with more advance timing at idle if you want to put up with more noise and longer crank times.
 
CorneliusRox said:
Higher compression would be that much better too! I run a 200rpm lower stall in my 47re and then use thicker fluid to bring it down more, and have a lot of my tuning set up to make it very drive-able between 800rpm to 3300rpm.
Click to expand...
How would higher compression help? Not trying to be a smarty-pants, just want a detailed explanation; which I am confidant you are capable of delivering.



CorneliusRox said:
Poor guy got his truck stolen... He had an arduino running a stock 6.0L turbo that was fully functioning, and then was using a smaller version of this pump I believe.
It was a 12V in a Chevy truck. Very custom build to make one super drive-able and reliable diesel.
I don't think I've seen him on in a long time since then. His name was ShadowTrooper I believe. I used to have his cell, maybe I'll see if he wants to hop on this.
Click to expand...

He had the exact same pump as I have (I know because the pump ID tags are the same number). I also know he never got it on the truck, & I know who has that pump now.
 
cut7 said:
I hope I didn't come across as a jack wagon, I just wanted to make sure we don't spread any misinformation about this pump. Lord knows, there's enough of that out there on the internet already!

I've had this pump for a few years and have done an enormous amount of research on it. At the risk of sounding a bit hubris, I probably know more about this pump than any ten people you'll run into.
Click to expand...

Mixed with ECM signals, called my friend and asked about it, he said pump bench gives a little bit over 10 volts to it like you said.

But are you sure about constant pressure valves ? I was told they leak some pressure to cut peak injection pressure when cam is at its fastest point. So with normal delivery valves you might get a little bit more fuel and higher peak pressures. I had big marine nozzles with H pump and it was hazing at idle. No different from P pump. Pop pressures were set to 300 bar.

Timing at idle was 4 degrees and at 1600 rpm 13 degrees, without load. It was Euro2 emission though, so retarded timing.
 
Leiffi said:
Mixed with ECM signals, called my friend and asked about it, he said pump bench gives a little bit over 10 volts to it like you said.

But are you sure about constant pressure valves ? I was told they leak some pressure to cut peak injection pressure when cam is at its fastest point. So with normal delivery valves you might get a little bit more fuel and higher peak pressures. I had big marine nozzles with H pump and it was hazing at idle. No different from P pump. Pop pressures were set to 300 bar.

Timing at idle was 4 degrees and at 1600 rpm 13 degrees, without load. It was Euro2 emission though, so retarded timing.
Click to expand...

What did you use to control the pump?
 
CorneliusRox said:
Have you done any testing on how fast it can actuate? I would assume there's some lag, so if you're using an Arduino to control this, look up smoothing functions. There's all sorts of free software out there for VGT control that would be very very similar to what you're doing.
Click to expand...

The rack moves within milliseconds of applying the voltage, so for all intents & purposes, it can be regarded as instantaneous. The smoothing functions are a good idea, though.
 
You must log in or register to reply here.
Back
Top