E67 2.4 LE5 With VVT any Ideas?

[Quasimotor]

Hello,
New here, just got my efilive for the VVT and VVE bonuses. I am confused looking at other VVT tables from other vehicles and I don'[t have the same options. Looks like only Cam Phasing vs cylinder airmass and RPM. I don't see any options for MAP or PE in my tuner.

So is that just what my ecm has or is there an upgrade/os/patch etc to get cam phasing vs map?

Now the real question I have is, am I looking at intake and exhaust cam advance or retard with the positive numbers?

I put a LSJ blower on this LE5 and I am curious if I am pumping boost out the pipe due to possible overlap type situation?

Thanks
Jim

[GMPX]

Jim, the cam positions 'are' based on airflow, I am not aware of any PE Mode cam table. Feel free to enlighten me.
How is the engine going now with the blower on it?

Thanks,
Ross

[scdyne]

As I understand it from the Factory service manual the 2.4L LE5 has 25 degrees of total cam movement for both the intake and exhaust. The default position before VVT is enabled on start-up is 0 degrees of camshaft actuation. However it's been stated before that it's unknown at this time weather that's 0 degrees TDC, -12.5 degrees BTDC, 12.5 degrees ATDC, or any value in the 25 degree range.

The control module calculates the optimum camshaft position through the following inputs:

Engine speed
Manifold absolute pressure (MAP)
Throttle position indicated angle
CKP (crankshaft position)
CMP (camshaft position)
Engine load
Barometric (BARO) pressure


My only issue is that for Quasimotor it's probably not enough timing and/or control to go into miller cycle on this engine. :sad: that would be nice.
Also I'm confident that getting a good handle on the VVT control for this engine means that we can control the dynamic compression better in boosted applications. Like when you strap an M62 to one or a Turbo.

[Quasimotor]

Jim, the cam positions 'are' based on airflow, I am not aware of any PE Mode cam table. Feel free to enlighten me.
How is the engine going now with the blower on it?

Thanks,
Ross
Hello Ross,
I was looking at cam phasing tables I found in the thread here: http://forum.efilive.com/showthread.php?t=6470&highlight=vvt

I see Vs gear, PE, MAp etc, but that is a single cam engine I believe. So the OS is most likely different.

As far as how it runs now, very well so far 255 HP and 234 Ft Lb. with the current tune and setup.

I wanted to tune in SD and play with the VVT so I came over to the efi Live side.

Jim

[ScarabEpic22]

The link you posted to is for the 4.2L I6, it has VVT on the exhaust cam only but is a DOHC engine. I understand that table, but I wish I knew how to tune the part throttle part of my LL8. :(

[GMPX]

Erik is correct, that thread was about a different PCM.
The E67 handles things very different.

[scdyne]

OK, I understand that a true VVT based map would be milti-dimensional, and programatically that's difficult - if not impossible - to express, but are the specific cam coefficients exposed for editing in the table and just (for now) not editable in the GUI?

Also do you have to be connected to the vehicle to see the Virtual VE stuff or is that a possible bug in 7.5.3 (Build 36)?
When I pulled the .tun from the car it showed the Airflow folder as red and included a number of red sub folders that had the V VE graphs in it. Now today I open my tune and nothing...

UPDATE! I read the Virtual VE tutorial!


To protect EFILive's intellectual Property, the virtual VE Tables are only available to EFILive customers that own a FlashScan device. To activate the Virtual VE Tables, you MUST connect the FlashScan interface to your computer BEFORE you start the EFILive Tuning Tool Software. The Virtual VE Table icons are displayed in red to indicate their protected status.

[Quasimotor]

So... did we decide 0 degrees was max advance or retard? Enquiring minds want to know. I'm looking for a strategy to begine cam phasing with boost.

Thanks
Jim

[scdyne]

To be honest I'll have to read through alldata a few more times to really get a grasp of what's being said. Some of the text is for other engines and applications with VVT so I have to what's valid for the LE5.

I'm of the opinion that it's time to take advantage of the little orange connectors on the FlashScan to figure this out.

Here is what we do know:

The camshaft position (CMP) actuator system is controlled by the control module. The control module sends a pulse width modulated 12-volt signal to each CMP actuator solenoid to control the amount of engine oil flow to a camshaft actuator passage. There are 2 different passages for oil to flow through, a passage for camshaft advance and a passage for camshaft retard. The camshaft actuator is attached to each camshaft and is hydraulically operated to change the angle of each camshaft relative to crankshaft position (CKP). Engine oil pressure (EOP), viscosity, temperature and engine oil level can affect camshaft actuator performance.
A locking pin keeps the CMP actuators in the parked position to avoid valve train noise upon engine start-up. The parked position is 0 degrees of camshaft actuation. The locking pin will release the actuator after the engine oil pressure is sufficient to overcome the locking pin spring pressure. The exhaust CMP actuators also have return springs. The return springs are necessary to assist the CMP actuators to return to the parked position due to the rotational inertia of the valve train components upon engine shutdown.
The camshaft position (CMP) sensor is triggered by a notched reluctor wheel built onto the exhaust camshaft sprocket. The CMP sensor provides four signal pulses every camshaft revolution. Each notch, or feature of the reluctor wheel is of a different size which is used to identify the compression stroke of each cylinder and to enable sequential fuel injection. The CMP uses a 5V reference circuit for both intake and exhaust. -AllData 2008

[scdyne]

OK, I searched all over the place and couldn't find any formal word on the isolation of the 0-5v inputs on the FlashScan.
So for the camshaft position sensors you can probably just piggyback on to them and run direct to 2 of the 0-5v inputs.
For the phasers you can either run them to the 0-12V inputs (if we can calculate accurate time between switching) or run them to the other 2 0-5V inputs.(ONLY if running 12v into the 0-5v wont mess the FlashScan up!)
A simple voltage divider circuit can drop the 12v signal to approximately 5 volts.
Then start logging MAP, RPM, TPS, inputs, etc.

The dumb question would be have you tried the following PIDs:
GM.EXPHAB1
GM.EXPHAB2
GM.EXPHDB1
GM.EXPHDB2
GM.EXCAM1DC
GM.EXCAM2DC
GM.EXPHEB1
GM.EXPHEB2

GM.INPHAB1
GM.INPHAB2
GM.INPHDB1
GM.INPHDB2
GM.INCAM1DC
GM.INCAM2DC
GM.INPHEB1
GM.INPHEB2

While I'm out to lunch I'll do some logging of the following parms to see if I get any feedback.

[Quasimotor]

I can log the cam phasing pids just fine (I wish I could log ETC wtf?).

I'm just trying to figure out if 0 is max advance or not. I hit 24 degrees at WOT under boost on the intake cam, and 18 degrees on the exhaust. To me I would think the VVT being used as a EGR function would also pump my precious boost out the exhaust?

Jim

[scdyne]

As I understand it, EGR works only during part throttle. It recirculates exhaust gas back in to the intake or in the case of VVT closes the exhaust valves earlier to prevent all of the exhaust gas from escaping, what is left in the engine is reintroduced during the next cycle.
So by looking at the exhaust cam map I would deduce that any numbers located in the area most expected to be used as EGR would be numbers that reflect the earliest exhaust cam closing time.
In my tables:
2667
That would be the high values.

And for that fact alone making an assumption with the intake cam I would suspect that the opposite is true.

That's still doesn't tell us what 0 degrees is, but at least I'm beginning to feel confident on the direction they are going..
Anyone care to please provide any contradictory/complementary information to help this along a little?

[scdyne]

As a continuation of this train of thought here are the cam profiles for the LE5 according to the ECOtec Cam sheet from GM.

LE5 Intake Cam - 12578511
Cam Peak Lift - 6.2551
Valve Peak lift - 10.542
Valve Timing - 135
Duration 1mm - 210.30
Valve area@1 - 1253.30

LE5 Exhaust cam - 12578512
Cam Peak Lift - 5.95143
Valve Peak lift - 10.0390
Valve Timing - -125
Duration 1mm - 195.40
Valve area@1 - 1092.70

[scdyne]

From the delphi.com
(http://delphi.com/manufacturers/auto/powertrain/gas/valvetrain/vcp/)



Control Valve Intake Exhaust Valve Overlap
Off Retard Advance Minimum
50% Intermediate: Flow is restricted to "hold" position.
100% Advance Retard Maximum



more on this later...