Responsive Turbo/compounds Thoughts

[TARM]

Dave,

What parameters are used to control the EBPV again. You have the EBPS, a temperature sensor of some sort?, what else?

 

[907DAVE]

In the desired map its RPM vs MFD, the % map is RPM vs EOT.

 

[TARM]

OK. Where does the EBPS output come into play?

 

[907DAVE]

Let me look, this i the first time I have paid any attention to this stuff.

 

[TARM]

OK

I was thinking off of EBPS for reading back pressure and how you would combine it with rpm to get a nice smooth operation curve for the VGT. You could do it off boost as well by sending the EPBS to the comp side of things vs the exhaust location. In fact a number of people have noticed better responsiveness and crisper shifts when you route the sensor to boost instead of exhaust for tunes where its still tuned on.

 

[907DAVE]

Whoops, brain fart. The "desired" appears to be the map that is referencing the EBPS. It looks like you set the pressures you want to see at that particular RPM and MFD,

 

[907DAVE]

If I have time tomorrow I will throw a scope on the truck and play around with it a bit to get a better idea of whats happening.

 

[TARM]

Whoops, brain fart. The "desired" appears to be the map that is referencing the EBPS. It looks like you set the pressures you want to see at that particular RPM and MFD,

OK that we can then work with. I knew it came into that somewhere. With that we can then fine tune off either boost or exhaust pressures. Then set the waste-gate controller to start to crack open at a level a bit higher than any max setting for the VGT.

 

[Derek@Vision Diesel]

I don't believe you have the same control on a OBS PCM, not that it matters to any of you... but I think on an OBS the BP valve is on or off. I am trying to find those tables in my Minotaur and am not seeing anything like Dave posted.

So this discussion is more than likely a 99-03 trial!

 

[Big Bore]

Interesting...

If the EBPV, system, does not have the voltage to actuate the turbo... Would a PCS?

Thinking there are 4 PWM outputs in a PCS, right?

Use two of the outputs?

I'm going to see if I can get a read on it tomorrow from the plug. Not sure what will happen since I have no EBP sensor or EBPV system at all.

Also, the PCM generates enough voltage to operate the IPR, just a thought.

Otherwise, a circuit to bump the voltage might be easier than a PCS.

 

[Derek@Vision Diesel]

I stand corrected, found in in the TDE1 file for OBS automatics.

 

[TARM]

SO it should work in either that's good for those that have not swapped over to new PCMs

 

[TrailerHauler]

I had always thought that the EBPV circuit was simply on or off, you guys think that the EBPV circuit, and WG circuit may have the capability of controling a VGT turbo?

And a PCS has 9 PWM outputs, so I suppose that would be another option for control.

 

[Big Bore]

Whoops, brain fart. The "desired" appears to be the map that is referencing the EBPS. It looks like you set the pressures you want to see at that particular RPM and MFD,

So it's scalable to the rpm and throttle pos? IOW if you wanted to you could have the EBPV opening and closing constantly?

 

[907DAVE]

Looks that way. And yes, open, closed and everything in between.

FWIW, the factory EBPS does not have to be used in this application, you can change the EBP transfer function to accept a sensor with a wider range. I dont think this will be an issue however.

 

[Big Bore]

Well the nice thing about solenoids is they don't take a lot of current to energize them. I was half joking when I suggested using the PCM and the factory EBPV circuit because it seemed too easy, but it also made sense because they operate much the same, and if the circuit has enough juice to energize a solenoid that opens and closes the EBPV, it seems on the surface plenty for the job of operating those vanes.


A sensor with a wider range would just allow more adjustability between fully open and fully closed correct? I can't imagine there needs to be a very fine adjustment for that, just smooth and responsive. Which is where I'm wondering if Tarms idea of referencing boost with the EBPS isn't a better idea.

 

[907DAVE]

The idea would be a sensor that reads higher pressures.

Anyone remember how much pressure the factory EBP sensor reads?

 

[Big Bore]

The idea would be a sensor that reads higher pressures.

Oh right, I forgot about those nasty codes, haven't had one in so long. LOL

Will the scale in the tuning allow for higher pressure reading?

 

[907DAVE]

Thats what the transfer function is about, but if it still wont accommodate and accurately display a 7 bar sensor the definitions can be changed to reflect a scale that high.

Just looked, the stock EBP sensor can read up to 50.5 psi, but the stock map in the tuning only reflects 40.6 psi.

Where's Bill when you need him...lol.

 

[TARM]

Dave,

Yes

It read to 43.5 in the PCM and its a simple .5v-4.5v 5 v sensor I think it goes up higher. That is also what it defaults to if you disconnect it or its clogged etc.. that is an absolute reading BTW not gauge