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Hi guys, trying to lose the opti on a stock 1996 LT1 and found that I can repin the harness to use the LS PCM. I downloaded a 2002 express van file from here with the 5.7, is that close enough to use on the LT1 as is? I will have to do a segment swap as I will be running a T56. If this file is not what I need does anyone have a start up and run file for the 96-97 F body LT1 using the 411 PCM? I can use either a bin file or HPT.
Thanks!
https://www.youtube.com/watch?v=nk3pvxJtYyU
I’m wondering if the video is the same as your conversion?
Similar but different, while he removed his opti completely the easierQuote:
Originally Posted by dave w
way is to use the opti for the cap and rotor and lose the opti sensor. The 4x
wheel and crank sensor is then used to fire the coil and injectors using the LS PCM.
common file to use to start is an early 5.7 express van file but I don’t know what
mods it needs for the LT1.
2002 L31 .bin files available on gearhead-efi: http://www.gearhead-efi.com/Fuel-Inj...rPro-Bin-FilesQuote:
Originally Posted by drptop70ss
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.
Correct, when this conversion is done it runs in batch fire mode. I can turn off VATS and any unneeded codes. As far as the MAF I can swap if needed, but I have to see if that is needed or not, same with the ICM. The 2001 express van tune has also been used, not sure if that is different than the 2002.Quote:
Originally Posted by dave w
No guarantees on this file but it will start and run. Then you can begin the tuning process. The posted file uses a regular 5 wire 2000-2006 Truck MAF
Here is the Express transfer function for the stock 3 wire Express MAF.
Code:MAF Sensor Air Flow Vs. Output Frequency
Hz gm/sec
1500 2.422
1625 2.805
1750 3.227
1875 3.695
2000 4.211
2125 4.789
2250 5.430
2375 6.133
2500 6.891
2625 7.703
2750 8.570
2875 9.484
3000 10.461
3125 11.516
3250 12.672
3375 13.945
3500 15.305
3625 16.742
3750 18.250
3875 19.836
4000 21.539
4125 23.359
4250 25.289
4375 27.352
4500 29.539
4625 31.875
4750 34.344
4875 36.938
5000 39.648
5125 42.398
5250 45.219
5375 48.133
5500 51.141
5625 54.273
5750 57.594
5875 61.102
6000 64.781
6125 68.641
6250 72.695
6375 76.953
6500 81.406
6625 86.055
6750 90.883
6875 95.906
7000 101.109
7125 106.500
7250 112.055
7375 117.805
7500 123.734
7625 129.844
7750 136.164
7875 142.672
8000 149.313
8125 156.188
8250 163.273
8375 170.570
8500 178.094
8625 185.859
8750 193.922
8875 202.250
9000 210.844
9125 219.719
9250 228.875
9375 238.320
9500 248.063
9625 258.102
9750 268.453
9875 279.102
10000 290.070
10125 301.352
10250 312.945
10375 324.867
10500 337.102
10625 349.672
10750 362.563
10875 375.781
11000 389.320
11125 403.188
11250 417.383
11375 431.906
11500 446.742
11625 461.906
11750 477.383
11875 493.180
12000 509.297
Thank you! I have found out that the stock LT1 MAF and ICM will work with the van tune file, so I will compare those MAF values as well. Much appreciated!
Quote:
Originally Posted by In-Tech
The X/Y isn't the same as the '0411 but this might help you extrapolate.
1996 Impala LT1 MAF Transfer function
1996 Vette MAF Transfer functionCode: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
Code: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
Thanks, my engine is from an F body but I would think the numbers would be the same as the vette. The B body uses a different smaller MAF sensor than the F body, at least it does on the 94/95s that I have had.
Quote:
Originally Posted by In-Tech
I wonder about '0411 injector parameters LT1 vs. L31?
1997 LT1 Camaro MAF Transfer funcion
Code:MAF Sensor Calibration Table
Hz gm/sec
1488 2.45
1616 2.88
1744 3.34
1872 3.87
2000 4.45
2128 5.12
2256 5.85
2384 6.64
2512 7.49
2640 8.41
2768 9.40
2896 10.46
3024 11.60
3152 12.82
3280 14.11
3408 15.48
3536 16.98
3664 18.60
3792 20.34
3920 22.22
4048 24.23
4176 26.35
4304 28.60
4432 30.97
4560 33.43
4688 35.99
4816 38.69
4944 41.54
5072 44.52
5200 47.66
5328 50.97
5456 54.42
5584 58.04
5712 61.81
5840 65.77
5968 69.92
6096 74.27
6224 78.82
6352 83.59
6480 88.58
6608 93.80
6736 99.25
6864 104.93
6992 110.88
7120 117.04
7248 123.42
7376 130.03
7504 136.87
7632 143.92
7760 151.14
7888 158.63
8016 166.31
8144 174.03
8272 182.36
8400 191.01
8528 200.07
8656 209.43
8784 219.12
8912 229.15
9040 239.52
9168 250.23
9296 261.30
9424 272.71
9552 284.48
9680 296.61
9808 309.10
9936 321.96
10064 335.20
10192 348.80
10320 362.77
10448 377.14
10576 391.88
10704 407.02
10832 422.55
10960 438.46
11088 454.78
11216 471.51
The LT1 ran 24 pound injectors stock, I have never looked at an LS PCM tune running at vortec (yet, still have to get this one loaded onto a PCM), if the tables are set up the same I will adjust if needed.Quote:
Originally Posted by dave w
Thank you again!Quote:
Originally Posted by In-Tech
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.
corvette and f body maf calibrations are quite different even though they use the same sensors. this is likely due to plumbing differences and also different afr goals in the upper ranges and gm using it for fine tuning there rather than targeting perfect calibration
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!Quote:
Originally Posted by 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.
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.
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.Quote:
Originally Posted by dave w
I have not experienced that at all. Any intake change even with that MAF has had to be adjusted for.Quote:
Originally Posted by In-Tech
I also just put a GenIV truck or G8 MAF on a setup. It works very well.
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?Quote:
Originally Posted by Fast355
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.Quote:
I wonder about '0411 injector parameters LT1 vs. L31?
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.
The injector parameters are from TunerCats OBD2 software:Quote:
Originally Posted by dave w
1997 LT1
Attachment 19521
2002 '0411 L31
Attachment 19522
2002 LS1 .bin file:
2002 LS1
Attachment 19524
do you by chance have the 1996 impala ss tune that you could share? thanksQuote:
Originally Posted by In-Tech
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.