Looking for tune file for LT1 1996 conversion to LS PCM

[drptop70ss]

Hiya,
You're welcome.
Those early MAF's aren't so good, especially with a non stock inlet air tract. Just trying to get you a decent starting point for your tuning process.

Appreciate it, will definitely have a non stock air intake, will be a 96 LT1 T56 put into a 61 Rambler wagon going on an 87 monte carlo SS chassis. One of my usual mutt builds!

[In-Tech]

Hiya,
Since you are building a new intake tract, use the 01-06 Truck MAF, it is much more forgiving to intake tube changes(Initial tune I posted is set up for that). Make sure it has at least 12" of straight tube after the MAF, and a high quality air filter before the MAF that will reduce any turbulence before the MAF. These things will drastically help you in the tuning process.

[Fast355]

The Express uses the same MAF as the F/Y car LT1 or early LS1. Should be able to copy the LT1 injector data into the 0411 tune. The Van tune will need some timing added to it. From there tune the VE tables with the MAF failed. Once you get the VE tables dialed in, re-enable the MAF and start tuning the MAF curve. The LT1 should pop right off on the van tune and run fairly well. But it will definitely be down on power without some timing added to it, van tune only has like 24° total advance.

Personally I would use a DBC P59 and use the Mexican GMT800 L31/5spd tune as a starting point. Segment swap over the 6spd trans segment from a 2005 CTSV that also had a P59 with the same OS.

[Fast355]

2002 L31 .bin files available on gearhead-efi: http://www.gearhead-efi.com/Fuel-Inj...rPro-Bin-Files

One of the challenges I see with the 96 LT1 vs. 2002 Express Van '0411 L31 are the spark tables. The 96 LT1 uses MAP Sensor tables for spark advance and the 2002 Express Van '0411 L31 uses MAF Sensor tables for spark advance.

The 2002 Express Van L31 Injectors are Sequential Fire.

Seems likely the LT1 would benefit using the 2002 Express Van '0411 MAF Sensor?

Seems likely the LT1 would benefit using the 2002 Express Van '0411 Ignition Module?

Seems likely the 2002 Express Van .bin file would require a VATS delete and possibly some Emission deletes also.

Same MAF sensor, same ICM on the vans as the LT1. LT1 is also sequential. Not hard toduplicate the LT1 timing curve if you know what the gm/cyl value is throughout the RPM range at WOT as well as what the MAP sensor reads at WOT. Then you can rinse and repeat for any rpm and load. Spark map in my aluminum head 383 L31 would probably be very close for an aluminum head LT1. I can post that tune.

[Fast355]

Hiya,
Since you are building a new intake tract, use the 01-06 Truck MAF, it is much more forgiving to intake tube changes(Initial tune I posted is set up for that). Make sure it has at least 12" of straight tube after the MAF, and a high quality air filter before the MAF that will reduce any turbulence before the MAF. These things will drastically help you in the tuning process.

I have not experienced that at all. Any intake change even with that MAF has had to be adjusted for.

I also just put a GenIV truck or G8 MAF on a setup. It works very well.

[dave w]

The Express uses the same MAF as the F/Y car LT1 or early LS1. Should be able to copy the LT1 injector data into the 0411 tune. The Van tune will need some timing added to it. From there tune the VE tables with the MAF failed. Once you get the VE tables dialed in, re-enable the MAF and start tuning the MAF curve. The LT1 should pop right off on the van tune and run fairly well. But it will definitely be down on power without some timing added to it, van tune only has like 24° total advance.

Personally I would use a DBC P59 and use the Mexican GMT800 L31/5spd tune as a starting point. Segment swap over the 6spd trans segment from a 2005 CTSV that also had a P59 with the same OS.

Is there a link to the DBC P59 Mexican GMT800 L31/5spd tune? Is there a possibly of posting the DBC P59 Mexican GMT800 L31/5spd tune to this thread?

[1project2many]

I wonder about '0411 injector parameters LT1 vs. L31?

Agreed. I would definitely expect to use injector tables that math the type of injector that is installed. The L31 Poppet style injectors are very different from traditional fuel injectors.

IME the stock one ton van injector voltage compensation is incorrect below 10V. If left stock our commercial vans have difficulty starting with a low battery and the exhaust is very rich at idle if the voltage drops. Leaving those tables intact could really mess with traditional injectors.

[dave w]

I wonder about '0411 injector parameters LT1 vs. L31?

The injector parameters are from TunerCats OBD2 software:

1997 LT1
LT1 Injector Tables.jpg


2002 '0411 L31
L31 Injector Tables.jpg

[dave w]

2002 LS1 .bin file:

2002 LS1

2002 LS1 Injector Tables.jpg

[bobcratchet555]

The X/Y isn't the same as the '0411 but this might help you extrapolate.

1996 Impala LT1 MAF Transfer function

    MAF Sensor Calibration Table
 
  Hz    gm/sec
   1488   1.89 
   1616   2.20 
   1744   2.55 
   1872   2.96 
   2000   3.40 
   2128   3.89 
   2256   4.44 
   2384   5.03 
   2512   5.69 
   2640   6.40 
   2768   7.15 
   2896   7.95 
   3024   8.80 
   3152   9.73 
   3280  10.73 
   3408  11.80 
   3536  12.95 
   3664  14.17 
   3792  15.49 
   3920  16.91 
   4048  18.44 
   4176  20.05 
   4304  21.74 
   4432  23.51 
   4560  25.36 
   4688  27.30 
   4816  29.32 
   4944  31.43 
   5072  33.62 
   5200  35.90 
   5328  38.30 
   5456  40.83 
   5584  43.49 
   5712  46.29 
   5840  49.23 
   5968  52.34 
   6096  55.61 
   6224  59.09 
   6352  62.72 
   6480  66.52 
   6608  70.48 
   6736  74.59 
   6864  78.85 
   6992  83.27 
   7120  87.85 
   7248  92.58 
   7376  97.45 
   7504 102.48 
   7632 107.66 
   7760 112.97 
   7888 118.44 
   8016 124.07 
   8144 129.86 
   8272 135.82 
   8400 141.95 
   8528 148.26 
   8656 154.73 
   8784 161.42 
   8912 168.33 
   9040 175.40 
   9168 182.82 
   9296 190.52 
   9424 198.49 
   9552 206.75 
   9680 215.30 
   9808 224.16 
   9936 233.34 
  10064 242.82 
  10192 252.63 
  10320 262.77 
  10448 273.23 
  10576 284.04 
  10704 295.18 
  10832 306.66 
  10960 318.48 
  11088 330.64 
  11216 343.14

1996 Vette MAF Transfer function

    MAF Sensor Calibration Table
 
  Hz    gm/sec
   1488   2.44 
   1616   2.86 
   1744   3.30 
   1872   3.80 
   2000   4.36 
   2128   4.99 
   2256   5.70 
   2384   6.47 
   2512   7.30 
   2640   8.20 
   2768   9.16 
   2896  10.19 
   3024  11.30 
   3152  12.48 
   3280  13.73 
   3408  15.09 
   3536  16.54 
   3664  18.11 
   3792  19.80 
   3920  21.59 
   4048  23.52 
   4176  25.55 
   4304  27.69 
   4432  29.94 
   4560  32.28 
   4688  34.69 
   4816  37.25 
   4944  39.91 
   5072  42.69 
   5200  45.58 
   5328  48.63 
   5456  51.83 
   5584  55.20 
   5712  58.77 
   5840  62.52 
   5968  66.47 
   6096  70.62 
   6224  74.96 
   6352  79.52 
   6480  84.27 
   6608  89.23 
   6736  94.41 
   6864  99.80 
   6992 105.41 
   7120 111.23 
   7248 117.27 
   7376 123.52 
   7504 129.98 
   7632 136.66 
   7760 143.54 
   7888 150.60 
   8016 157.89 
   8144 165.39 
   8272 173.11 
   8400 181.01 
   8528 189.24 
   8656 197.90 
   8784 206.75 
   8912 215.86 
   9040 225.23 
   9168 234.88 
   9296 244.77 
   9424 254.94 
   9552 265.36 
   9680 276.05 
   9808 286.99 
   9936 298.20 
  10064 309.66 
  10192 321.39 
  10320 333.38 
  10448 345.63 
  10576 358.13 
  10704 370.89 
  10832 383.91 
  10960 397.19 
  11088 410.73 
  11216 424.52

do you by chance have the 1996 impala ss tune that you could share? thanks

[drptop70ss]

Been a little bit, I wasn't getting notifications that this thread was being replied to but wanted to say thank you all for the help. Since I started this post I actually found an 02 Express van in the junkyard and grabbed the PCM. Turned out to be a 156 OS which is a common one and I could read it with tunerpro. This one was a factory 350/4L80e tune, and I did a segment swap to make an M6 tune using an 02 z28 file for the transmission side. I still have to update the injector data, thank you for that help! I will be running the stock 96 LT1 injectors since the engine is stock. With the mention that the LT1 uses the MAP sensor for spark tables, should I fail the MAF and just run in SD mode, or better to keep the MAF? I do not have a 96 timing table to look at, but I do have a 95 LT1 tune to reference that I can copy over to the van tune. Because I will be using the 4x crank wheel it will be running in batch fire mode, no more sequential.