2bar Map Sensor w/ MAF and Stock OS?

[ferocity02]

Can I run a 2bar MAP sensor with a 12212156 OS in a turbo application using the stock MAF? I would like the ability to log boost and the 1 bar maps cuts out around 104 kPa in my logs. I have a GM 2 bar MAP sensor on the shelf.

If this is possible how do adjust for it in the tune?

[ScarabEpic22]

Yes you can run it and it will log in the Scan tool, but you will be out of resolution in the OS itself. Whatever the highest g/cyl spark and VE values are is what will be used in boost (read, you will have no control over fuel and spark once you get into boost. 100/105kPa values will be used even at 200kPa in a stock OS. And REP will happen unless you change the rationality test values.). If you hit the 512g/s limit of the MAF, the PCM will use the highest value for fueling as well.

Time to upgrade to a COS, it's free and doesnt take much work if you script your existing tune into it.

Go into Engine Diagnostics->MAP and enter the values in there.

[ferocity02]

Thanks for the reply! What is involved in swapping the MAP sensors? What needs to be changed in the tune so it knows its a 2 bar sensor instead of a 1 bar sensor?

I realize the tune will "max out" at 1 bar. My tuner for one reason or another is not doing a COS.

[ScarabEpic22]

Thanks for the reply! What is involved in swapping the MAP sensors? What needs to be changed in the tune so it knows its a 2 bar sensor instead of a 1 bar sensor?

I realize the tune will "max out" at 1 bar. My tuner for one reason or another is not doing a COS.

I dont know who you're using for tuning, but I would never recommend using a stock OS for a boosted application. That's the entire reason that EFILive and HPTuners spent lots of time and money to develop the COSs. The only reason I can think of is that you cant use a MAF in a 2+ Bar OS, if you're dead set on keeping it then you'll have to run the stock OS. Watch your g/s values, if you get close to 512g/s, you're going to be better off ditching the MAF and going 2/3Bar SD with a COS as you will run out of resolution.

Depending on the MAP sensor you use, you'll need to change 2 or 3 tables in the Engine Diag->MAP section. I dont remember offhand as I dont do many LS1s.

[ferocity02]

I think that was it. He probably thinks the MAF will support my goals, which is around 600rwhp.

Thanks again!

[joecar]

12212156 easily upgrades to COS3/02020003 or COS5/0202005 (the upgrade is so simple it is pretty much thoughtless) which provide a boost VE table which works with the 2-bar MAP sensor (not to mention a boost spark table).

[picnic_george]

Let me get this 100% straight. There is no way to run a boost ve/spark tables and MAF at the same time? Obviously there isn't a point on a vehicle with 30psi but a car running 8psi I can see the advantage of doing both. Unless of course I'm missing something. And why can't or don't we have that option.

Thanks
Kris

[ferocity02]

Let me get this 100% straight. There is no way to run a boost ve/spark tables and MAF at the same time? Obviously there isn't a point on a vehicle with 30psi but a car running 8psi I can see the advantage of doing both. Unless of course I'm missing something. And why can't or don't we have that option.

Thanks
Kris

I too would like to know this. Can we run a COS with tables for boost with the MAF?

[joecar]

Let me get this 100% straight. There is no way to run a boost ve/spark tables and MAF at the same time? Obviously there isn't a point on a vehicle with 30psi but a car running 8psi I can see the advantage of doing both. Unless of course I'm missing something. And why can't or don't we have that option.

Thanks
Kris

Kris,

The EFILive COS's allow you to run MAF with boost (at the same time)...

edit: the COS tutorial says to disable the MAF... but just go ahead and try it.


[ I don't know where you got the MAF-less-only idea from...!? ] edit: oh, I see it in the COS upgrade pdf, sorry my mistake ]


Of course, you have to watch that the MAF does not exceed 512 g/s (limitation of LS1 0411 PCM).

[joecar]

The feature of the COS's is that they allow you to run adaptive spark (HO/LO park tables) when the MAF is failed...


( this is the idea that get's inverted into a misconception )