can i run the maf with the magnacharger ?

[supershift67]

I was wondering if I should change to speed density and get a different MAP sensor or just stay with the maf. this is on a 2007 lq4 with 4l80e. It is also with a MP122 maggie. The engine is all stock right now but I will be running a smaller pulley. I am guessing I will only get about 10 psi max out of the supercharger. I am also still running the stock MAP.

[joecar]

You can run the MAF, but you will have to scale down the IFR/VE/MAF tables to avoid the PCM's 512 g/s MAF limit...

and you will have to shift/scale down any table that references airmass (g) or airflow (g/s).

[supershift67]

You can run the MAF, but you will have to scale down the IFR/VE/MAF tables to avoid the PCM's 512 g/s MAF limit...

and you will have to shift/scale down any table that references airmass (g) or airflow (g/s).

would it be easier to just do speed density. I was thinking of doing it anyway if I can figure out which MAP sensor to run.

[joecar]

Yes, it would be easier to go SD...

you should run a COS and a 2-bar MAP.

[supershift67]

Yes, it would be easier to go SD...

you should run a COS and a 2-bar MAP.
alright, I will get a MAP sensor and I will try to figure out the COS. I am sure I will have more questions. Thanks for the help

[joecar]

Oh, for 2007 LQ4 there will not be a COS...


you might run the 2-bar MAP, and scale all the tables that reference MAP (or VAC)...

(i.e. 100kPa is really 200kPa, so each table now has twice the range but half the resolution)

edit: corrected typo

[ScarabEpic22]

Oh, for 2007 LQ4 there will not be a COS...


you might run the 2-bar MAP, and scale all the tables that reference MAP (or VAC)...

(i.e. 100kPa is really 200kPa, so each table now has twice the range but half the resolution)

I think you meant 2 Bar MAP Joe... :D

But yes, you'll need to scale the tune 50%. The last LS1 COSs I believe were for 2005.

[joecar]

Ah, thanks Erik, yes, I meant 2-bar ( I was typing quickly and not proof reading :doh:)

to anyone reading along: it's pretty obvious that the 1-bar MAP would peg at ~100kPa.

[supershift67]

o.k. Is there any reading material on how to scale the MAP to 2 bar. I searched some and couldnt find anything. Thanks again guys.

[supershift67]

o.k. Is there any reading material on how to scale the MAP to 2 bar. I searched some and couldnt find anything. Thanks again guys.
I did find this post on 2 bar. http://forum.efilive.com/showthread.php?594-2-bar-map-setup Does this seem correct even though I am not running a cos. I am also trying to switch everything over to speed density closed loop. Do I just have to set the maf to not reported?

[joecar]

You do that only if you're running a COS...

if you're running the OS (and not a COS) where you will be scaling the IFR/VE/MAF 50% (like Erik said) you want the 2-bar MAP with no MAP scaling

(the scaling/shifting will be in the tables that reference MAP or VAC or airmass or airflow)

i.e. when the MAP voltage is full scale the PCM thinks it is 100kPa but the tables have been scaled/shifted to recognize this as 200kPa... but your log files will say 100kPa.

[supershift67]

How do I scale the IFR and VE 50%. I shouldnt have to worry about the MAF since I am not running one correct?

[joecar]

You multiply the IFR, VE, MAF by 0.5.

Then you shift down any table that references airmass or airflow (shift the data from the axis 100% value down to the 50% value).

[supershift67]

I still havent got this running yet,I repainted the car in the meantime so Im getting back to getting this thing figured out. I talked to a couple tuners and one said I could switch the TAC module to a 2004 and then change the computer software to match. Is there a way to change the software and keep my credit for tuning or would I end up with a 2004 vin number and have to by another credit. I basically just want to get the car running to check my wiring before it goes to the dyno.
I was also wondering if I use the MAF on the 2007 ecu and put the stock MAP back in or should I keep the 2 bar and just scale it down. What would be easiest? thanks

[joecar]

The VIN license actually licenses the PCM/ECM serial number regardless of OS/VIN...

i.e. with the same same PCM, you can change the OS/VIN without requiring any new licenses credits.

[supershift67]

The VIN license actually licenses the PCM/ECM serial number regardless of OS/VIN...

i.e. with the same same PCM, you can change the OS/VIN without requiring any new licenses credits.
So do you think I can use a cos from a 2004 and load it on my ecu then use the 2004 TAC module? I have been looking at the wiring diagram and so far the wiring all looks the same from 2004 to 2007.

[joecar]

I have been told to match up same-year TB/TAC components to PCM.

[supershift67]

1892818929 I decided to just run the stock map and maf. I copied a radix tune i found but I cant run it long enough and keep getting a p0101 maf code. Im not sure what else I need to do to make this right. Since the stock map cant read boost do I have to do anything with the map so it runs off of the maf only?

[joecar]

No, you need the MAP sensor.

You can try running without the MAF (this is what happens when DTC P0101 shows up)... but to do this the VE table has to be correct...

but take note: in your tune file, the MAF DTC's are set to Not-Reported in table C6001, this prevents the PCM running from the VE table.

[supershift67]

I looked at c6001 under p0101 p0102 and p0103 and they all show B 2 trips.Am I looking at the wrong thing.
I was also just going to lower B0120 to 1000 instead of 4000 so it would use the maf instead of the map and then just tune the ve table and run off of that. Otherwise how does magnacharger tune with the stock map and maf?

[joecar]

I looked at c6001 under p0101 p0102 and p0103 and they all show B 2 trips.Am I looking at the wrong thing.
You are correct, sorry my cross-eyed mistake... set those to A 1-Trip just in case you ever need to run VE-only (i.e. the MAF should be failed immediately in order to run from VE only).



I was also just going to lower B0120 to 1000 instead of 4000 so it would use the maf instead of the map and then just tune the ve table and run off of that. Otherwise how does magnacharger tune with the stock map and maf?You can go as low as 400 or even zero...

doing that uses the MAF-only and avoids the VE althogether... (so now you would be correcting the MAF and calculating a new VE from the MAF, you wouldn't be running from that VE just yet).

take note that the MAP sensor is used always by all modes (VE-only, MAF-only, MAF/VE).

Problem with running the MAF with boost: the LS1 PCM's internally limit the MAF to 512 g/s... so to run MAF you have to scale the MAF (and other tables)... it might just be easier to run VE-only, to do this you have to make the MAF fail.