DI/PI 3.5L Ecoboost

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04-17-2018
Higgs Boson

DI/PI 3.5L Ecoboost

We can only choose between DI or PI totaling up to 100% of required fuel, but we cannot choose to run 100% DI capacity and 100% PI capacity, increasing fueling for more power? Even if we add an extra lift pump, is there a way to run full DI and then bring in PI on top of it rather than taking from one to give to the other?

Also, are the valve events and SOI/EOI numbered based on 0 being TDC "after spark" and 360 being TDC "before intake stroke?" so 337 for SOI is 23 degrees after TDC during the intake stroke and 37 for EOI about 30 degrees before spark if spark lead is 7 degrees?"
04-17-2018
Steven@HPTuners

Quote:

Originally Posted by Higgs Boson

We can only choose between DI or PI totaling up to 100% of required fuel, but we cannot choose to run 100% DI capacity and 100% PI capacity, increasing fueling for more power? Even if we add an extra lift pump, is there a way to run full DI and then bring in PI on top of it rather than taking from one to give to the other?

Also, are the valve events and SOI/EOI numbered based on 0 being TDC "after spark" and 360 being TDC "before intake stroke?" so 337 for SOI is 23 degrees after TDC during the intake stroke and 37 about 30 degrees before spark if spark lead is 7 degrees?"

I think you're thinking about the blend wrong. The idea is to achieve the demanded fuel mass in terms of current fuel demand. If you're demanding 8lb/min, and PI/DI Blend is 50%, you're running 4lb/min PI and 4lb/min DI. It does not mean run PI at 50% capacity and DI at 50% capacity. If your PI Capacity is 5lb/min, DI 3lb/min, and your demand is 5lb/min with a blend of 60% DI, you get all 3lb/min DI, and 2lb/min PI. Your DI is at 100% capacity while your PI is only at 40% capacity.

As to SOI/EOI, its * BTDC Power Stroke, so 0 = TDC start of power stroke, 360 = TDC start of intake stroke. This applies to anything ~2012+. Some of the older controllers defined SOI in terms of *ATDC Power Stroke IIRC and had correspondingly different number sets.
04-17-2018
Higgs Boson

Quote:

Originally Posted by Steven@HPTuners

I think you're thinking about the blend wrong. The idea is to achieve the demanded fuel mass in terms of current fuel demand. If you're demanding 8lb/min, and PI/DI Blend is 50%, you're running 4lb/min PI and 4lb/min DI. It does not mean run PI at 50% capacity and DI at 50% capacity. If your PI Capacity is 5lb/min, DI 3lb/min, and your demand is 5lb/min with a blend of 60% DI, you get all 3lb/min DI, and 2lb/min PI. Your DI is at 100% capacity while your PI is only at 40% capacity.

As to SOI/EOI, its * BTDC Power Stroke, so 0 = TDC start of power stroke, 360 = TDC start of intake stroke. This applies to anything ~2012+. Some of the older controllers defined SOI in terms of *ATDC Power Stroke IIRC and had correspondingly different number sets.

I probably phrased it wrong but that is what I meant. Maybe a better question is, where does the system max out? For example, the DI system on my Z06 will go to low 700rwhp and then you either add meth or a secondary port system to keep it going.

Having both stock they only run together up to 100% of demand so my question I guess it really do we get extra capacity out of the system or anything over stock power levels will need new port injectors?

Has anyone tried altering the DI/PI fueling mixes to any benefit? Wouldn't setting the blend table to 50% give the most headroom to each system?

ECM 7304 DI EOI Clip says it is the EOI clip for intake only fueling mode but the value at 110 psi rail pressure (which would be all the time right?) is 120 degrees...wouldn't that be during compression, not intake? And why would a locally posted tuning guide recommend changing this value to 700? This give the DI permission to spray through spark and exhaust stroke or does this table use a different method?

SOI Minimum at 337 - Max Inj Angle of 220 = EOI 117 (which is close to the stock table value of 120)
The highest value in the single injection intake table is 336 which goes will with SOI Min at 337.

If we want to open up injection window then wouldn't we need to raise SOI Min? (over 360 would spray before intake stroke and possibly out the exhaust valve (how does fueling change with the variable valve timing and the overlap moving around?)

Wouldn't we also want to LOWER EOI Clip from 120 to something a suitable amount before spark (personally I wouldn't think I would want to change that from 120)

Wouldn't we only want to increase Max Injection Angle to the difference between SOI Min and EOI Clip?

Wouldn't we also want to raise the higher values in the Single Injection Intake table to max out at the new SOI Min?

Are there tables available for PI injection timing?
05-29-2018
Higgs Boson

bump for some discussion...

also, do we have separate scanner pids for PI and DI pulse width and duty cycle?

HPT guys, any info on this?
05-29-2018
Puggyberra

Sorry, I missed this thread the first time you posted it.

Quote:

Originally Posted by Higgs Boson

I probably phrased it wrong but that is what I meant. Maybe a better question is, where does the system max out? For example, the DI system on my Z06 will go to low 700rwhp and then you either add meth or a secondary port system to keep it going.

Having both stock they only run together up to 100% of demand so my question I guess it really do we get extra capacity out of the system or anything over stock power levels will need new port injectors?

You should get extra capacity out of the combined system compared to the DI only of the previous years.

Quote:

Originally Posted by Higgs Boson

Has anyone tried altering the DI/PI fueling mixes to any benefit? Wouldn't setting the blend table to 50% give the most headroom to each system?

Yes, but DI has several advantages being more power output compared to PI as well as cooling benefits, so you want to run more towards the DI side until you need the extra overhead from PI.

Quote:

Originally Posted by Higgs Boson

ECM 7304 DI EOI Clip says it is the EOI clip for intake only fueling mode but the value at 110 psi rail pressure (which would be all the time right?) is 120 degrees...wouldn't that be during compression, not intake? And why would a locally posted tuning guide recommend changing this value to 700? This give the DI permission to spray through spark and exhaust stroke or does this table use a different method?

If you?re referencing metroplex?s guide his was based on the previous ecu os Steven mentioned, so that 700 would allow injection until 20 BTDC of the compression stroke. The newer ecu?s reference degrees BTDC of compression.

Quote:

Originally Posted by Higgs Boson

SOI Minimum at 337 - Max Inj Angle of 220 = EOI 117 (which is close to the stock table value of 120)
The highest value in the single injection intake table is 336 which goes will with SOI Min at 337.

If we want to open up injection window then wouldn't we need to raise SOI Min? (over 360 would spray before intake stroke and possibly out the exhaust valve (how does fueling change with the variable valve timing and the overlap moving around?)

Wouldn't we also want to LOWER EOI Clip from 120 to something a suitable amount before spark (personally I wouldn't think I would want to change that from 120)

You?re correct on all 3 of these, you want to expand the window and allow a larger window. Considerations to avoid spraying on the exhaust valves and not to spray too close to TDC combustion stroke are kind of on you. I will run EOI clip down to 70 personally, but I?m not saying that?s guaranteed safe, just that it?s been done. I posted in a different thread a while back and broke down how I expanded that window with a DI only system on the newer ecu OS.

Quote:

Originally Posted by Higgs Boson

Wouldn't we only want to increase Max Injection Angle to the difference between SOI Min and EOI Clip?

Wouldn't we also want to raise the higher values in the Single Injection Intake table to max out at the new SOI Min?

Yes and yes. The only consideration to keep in mind is the Fuel injection tables don?t reference rpm, so you could wind up in a cell demanding a large injection window due to low rpm with low rail pressure but a higher air load. If that happened when the ecu is still trying to build boost the valves might be overlapping more, so you?d want to take care to avoid spraying on the exhaust valves to ensure you avoid LSPI. If you look in the variable cam timing tab there are valve advance and retard limits you could work off as well.

Quote:

Originally Posted by Higgs Boson

Are there tables available for PI injection timing?

I don?t have any information on this, maybe Eric or Steven can chime in?
05-29-2018
Higgs Boson

Thank you puggy
06-06-2018
Josh.Chauvin1

looks like in any blend setting the FPDM only lets the lift pump command 50% Duty cycle even at a 90% setting still hindering fuel flow??
06-07-2018
Steven@HPTuners

Quote:

Originally Posted by Josh.Chauvin1

looks like in any blend setting the FPDM only lets the lift pump command 50% Duty cycle even at a 90% setting still hindering fuel flow??

The duty cycle you see is for the FPDM. The actual output is different. It translates the values you see there.
5-50% = x2 to actual fuel pump DC = 10-100%
75% = Fuel Pump Off (the FPDM will accept anything in the 67.5% to 82% as a valid "Off" command)

Anything else is undefined, and the FPDM defaults to off.
11-03-2018
metroplex

On the SHO, I raised the Max Injection angle from 220 to 290, and changed the EOI clip table. I think the Max Injection Angle did the trick though.

On the newer 2.7 EcoBoost, I tried a number of things and always ran into the Comb STability and Insufficient Fuel limits. I raised Max Injection Angle from 220 to 330. Then I lowered the EOI clip table down to 30. That still didn't quite work. I tried changing the Max DC to 2 and that worked, but I understand the safety concerns with doing this as I'd possibly run out of fuel. I wish there was a better guide to describe how to exactly increase injection window on the older and newer ECU OS's.
11-07-2018
metroplex

So after talking with Puggyberra, I think I figured it out.

720 - SOI Minimum = Minimum in BTDC (MIN)
MIN - EOI Clip = Max Inj Angle

So if SOI Min is 383, and EOI Clip at 2150 psi is 120, then the Max Inj Angle should be 217.
This coincides with what the factory settings were (383, 120, 220).

After using this logic, I increased (numerically decreased EOI Clip) and re-adjusted Max Inj Angle to match it. I no longer have the Insufficient Fuel error even when using the paddles on the Fusion Sport.
11-07-2018
Higgs Boson

Quote:

Originally Posted by metroplex

So after talking with Puggyberra, I think I figured it out.

720 - SOI Minimum = Minimum in BTDC (MIN)
MIN - EOI Clip = Max Inj Angle

So if SOI Min is 383, and EOI Clip at 2150 psi is 120, then the Max Inj Angle should be 217.
This coincides with what the factory settings were (383, 120, 220).

After using this logic, I increased (numerically decreased EOI Clip) and re-adjusted Max Inj Angle to match it. I no longer have the Insufficient Fuel error even when using the paddles on the Fusion Sport.

yeah, see post #3. ;-)
11-07-2018
metroplex

Quote:

Originally Posted by Higgs Boson

yeah, see post #3. ;-)

I saw that but I just wanted a simple math equation to help understand it. I accidentally got it close on the SHO which is how it worked out.
09-11-2020
engineermike

Quote:

Originally Posted by Higgs Boson

Also, are the valve events and SOI/EOI numbered based on 0 being TDC "after spark" and 360 being TDC "before intake stroke?" so 337 for SOI is 23 degrees after TDC during the intake stroke and 37 for EOI about 30 degrees before spark if spark lead is 7 degrees?"

Resurrecting and old thread here...

If 0 is TDC after spark and 360 is TDC after exhaust/before intake, then why wouldn?t 337 be 23 deg BTDC before the intake stroke begins? It?s a question of which way we are counting, right?

With the cam timing, the calibration says that ivo is 340 and evc is 369 for the 2018+ coyote. I always took that to mean those are degrees after TDC ?after spark?. That puts Ivo at 20 deg BTDC and evc at 9 deg ATDC. When you look at the cam timing tables, this makes sense because most of the cam timing values for mapped points are positive/retard so the cams move in the right direction from baseline.
10-04-2020
engineermike

I think I figured out my answer above, most certainly it’s counting in reverse from after-spark tdc.

But I ran into a new problem. I changed my di blend to 90% and max DC to 0.1 to see what happens and test the limit. Nothing happened. It fueled it with 90% di, reaching 130+ deg of injection angle, no throttle cut, good lambda. So what gives?