Getting custom 95 L67 EPROM from GMTuners...
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Getting custom 95 L67 EPROM from GMTuners...
....and I am wondering what I should have for programming changes.
So far I'd like:
3 or 4* more timing advance,
Remove speed limiter
up shift points by 150-250 rpm
But I'm wondering what I should have done for the fuel curve? Will they now how to adjust it to match? I'm assuming so, but in case they need info I'm kinda at loss as I'm not all that knowledgeable on the fuel systems on these engines.
So far I'd like:
3 or 4* more timing advance,
Remove speed limiter
up shift points by 150-250 rpm
But I'm wondering what I should have done for the fuel curve? Will they now how to adjust it to match? I'm assuming so, but in case they need info I'm kinda at loss as I'm not all that knowledgeable on the fuel systems on these engines.
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Do you have a scan tool?
You should reeeeaaaallly get one if your going to do a custom chip.
Depending on where your at right now, you may want to decrease timing to stop predetonation.
Your WOT O2 mV'* will give a good estimation of how much more fueling you may or may not need. Also, your LTFT'* will show how much your computer is adjusting to a lack of, or too much fuel during non WOT situtations.
And depending on your KR situation right now, you could advance the timing like you want.
Seriously though it'* not worth getting a custom chip unless you know what your car is doing right now.
You should reeeeaaaallly get one if your going to do a custom chip.
Depending on where your at right now, you may want to decrease timing to stop predetonation.
Your WOT O2 mV'* will give a good estimation of how much more fueling you may or may not need. Also, your LTFT'* will show how much your computer is adjusting to a lack of, or too much fuel during non WOT situtations.
And depending on your KR situation right now, you could advance the timing like you want.
Seriously though it'* not worth getting a custom chip unless you know what your car is doing right now.
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Originally Posted by 95naSTA
Do you have a scan tool?
You should reeeeaaaallly get one if your going to do a custom chip.
Depending on where your at right now, you may want to decrease timing to stop predetonation.
Your WOT O2 mV'* will give a good estimation of how much more fueling you may or may not need. Also, your LTFT'* will show how much your computer is adjusting to a lack of, or too much fuel during non WOT situtations.
And depending on your KR situation right now, you could advance the timing like you want.
Seriously though it'* not worth getting a custom chip unless you know what your car is doing right now.
You should reeeeaaaallly get one if your going to do a custom chip.
Depending on where your at right now, you may want to decrease timing to stop predetonation.
Your WOT O2 mV'* will give a good estimation of how much more fueling you may or may not need. Also, your LTFT'* will show how much your computer is adjusting to a lack of, or too much fuel during non WOT situtations.
And depending on your KR situation right now, you could advance the timing like you want.
Seriously though it'* not worth getting a custom chip unless you know what your car is doing right now.
I will definitely get in touch with Nate again and do some more testing before I order the prom.
I know I looked at the tables you mentioned above, but don't remember what I was seeing, but I do recall they looked decent. I'll definitely rescan to verify what is there.
BTW, I believe I have a oil leak, possibly from the rear valve cover or head gasket, so this will need to be fixed too -too bad this is happening now -I hoped I wouldnt have to take them off before I go in for the cam swap. :(
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When I started doing tuning agian this year, Ryan (from gmtuners) sent me this:
Scan Tool Information Request (usually needed for modified engines only)
The following information is essential in order for a burned EPROM to be fully compatible with your modified engine combination to have good drivability. You can use this example to list information that can help me correctly burn a new chip or modify a stock program for your engine. Again, you only need to fill this section out if your engine is NOT stock.
It is imperative that the following information below listed in the across row be from the same frame of data that the scan tool supplies. Because of the vast amount of data required, it is best to set the scan tool to record a driving event for playback at a later time in which you can safely write down the information recorded. An example of the main tables of information I need is given below in BOLD and examples of the data that you will be recording is given in ITALIC print.
Fuel Table A
Short Term Trim or Long Term Trim or
RPM Intergrator (INT) Block Learn (BLM) MAP or MAF O2 voltage Loop Status Throttle %
2450 124 120 62 kpa MAP 0.843v closed 8
2875 126 122 75 kpa MAP 0.542v closed 15
1525 128 134 15 g/* AirFlow 0.240v closed 6
3200 144 140 40 g/* AirFlow 0.353v closed 25
In the above tables, it is not necessary for frames of data to be given for fuel in which there is a INT (short term) and BLM (long term) count at 128, or within +/- 4 counts of 128.
Timing Table A
RPM MAP or LV8 (load) Knock Retard Degrees O2 voltage Throttle % Vehicle Speed Spark Advance
3500 88 kpa MAP 2 0.825v 76 25 mph 19 deg
4575 96 kpa MAP 4 0.758v 89 73 mph 15 deg
2700 208 LV8 (filtered load) 1 0.987v 67 15 mph 13 deg
5425 254 LV8 (filtered load) 3 0.857v 100 (wot) 40 mph 10 deg
In the above tables, it is not necessary for frames of data to be given for the timing table if the knock retard is 0 degrees.
www.gmtuners.com
For our pcms,
INT = ShortTermFuelTrim (STFT)
BLM = LongTermFuelTrim (LTFT)
You want to have these values be as close to 128 or 100% as possible. The STFT will vary a lot but should hover around the 128/100% value.
Scan Tool Information Request (usually needed for modified engines only)
The following information is essential in order for a burned EPROM to be fully compatible with your modified engine combination to have good drivability. You can use this example to list information that can help me correctly burn a new chip or modify a stock program for your engine. Again, you only need to fill this section out if your engine is NOT stock.
It is imperative that the following information below listed in the across row be from the same frame of data that the scan tool supplies. Because of the vast amount of data required, it is best to set the scan tool to record a driving event for playback at a later time in which you can safely write down the information recorded. An example of the main tables of information I need is given below in BOLD and examples of the data that you will be recording is given in ITALIC print.
Fuel Table A
Short Term Trim or Long Term Trim or
RPM Intergrator (INT) Block Learn (BLM) MAP or MAF O2 voltage Loop Status Throttle %
2450 124 120 62 kpa MAP 0.843v closed 8
2875 126 122 75 kpa MAP 0.542v closed 15
1525 128 134 15 g/* AirFlow 0.240v closed 6
3200 144 140 40 g/* AirFlow 0.353v closed 25
In the above tables, it is not necessary for frames of data to be given for fuel in which there is a INT (short term) and BLM (long term) count at 128, or within +/- 4 counts of 128.
Timing Table A
RPM MAP or LV8 (load) Knock Retard Degrees O2 voltage Throttle % Vehicle Speed Spark Advance
3500 88 kpa MAP 2 0.825v 76 25 mph 19 deg
4575 96 kpa MAP 4 0.758v 89 73 mph 15 deg
2700 208 LV8 (filtered load) 1 0.987v 67 15 mph 13 deg
5425 254 LV8 (filtered load) 3 0.857v 100 (wot) 40 mph 10 deg
In the above tables, it is not necessary for frames of data to be given for the timing table if the knock retard is 0 degrees.
www.gmtuners.com
For our pcms,
INT = ShortTermFuelTrim (STFT)
BLM = LongTermFuelTrim (LTFT)
You want to have these values be as close to 128 or 100% as possible. The STFT will vary a lot but should hover around the 128/100% value.
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Wolfedog50
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05-08-2003 01:31 PM