OBDII conversion - troubleshooting time
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Joined: Feb 2003
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From: Philly
How are you matching up the spark tables?
The OBD1 tables would be LV8 (value proportional to the amount of air flowing in) vs RPM.
And the OBD2 tables are MAP based IIRC. So, kPa vs. RPM.
I guess maybe your interpolating between the max and min values?
I don't know if you have seen this tuner guide & info, but it could be very helpful:
http://wiki.opentuner3800.com/index.php?title=Main_Page
The OBD1 tables would be LV8 (value proportional to the amount of air flowing in) vs RPM.
And the OBD2 tables are MAP based IIRC. So, kPa vs. RPM.
I guess maybe your interpolating between the max and min values?
I don't know if you have seen this tuner guide & info, but it could be very helpful:
http://wiki.opentuner3800.com/index.php?title=Main_Page
Thread Starter
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From: In your garage, swipin' da lug nutz
To quote from the OTC (Ottawa Tool Company) Scanner Manual " LV8, Filtered Load Variable (LV
, In the filtered load variable mode, a number will be displayed that is proportional to the measurement of the amount of air being displaced per cylinder. The filtered load variable replaces the MAP sensor in some applications." So a MAF reading is grams/second, and a LV8 is a number that is a proportion.
Therefore in a MAP set of calibration tables you have VE tables, and in a MAF you have LV8.
, In the filtered load variable mode, a number will be displayed that is proportional to the measurement of the amount of air being displaced per cylinder. The filtered load variable replaces the MAP sensor in some applications." So a MAF reading is grams/second, and a LV8 is a number that is a proportion. Therefore in a MAP set of calibration tables you have VE tables, and in a MAF you have LV8.
http://www.diy-efi.org/gmecm/papers/tunetip.html
The numbers I replaced were not very far off individually, but as a whole, changed the map quite a bit. Also, the 1995 L67 numbers I was basing from where very exact, but rounded to the nearest whole number in the HP Tuner.
And that site....helps out a great deal!
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From: Philly
Originally Posted by sandrock
Got it from this site right here:
http://www.diy-efi.org/gmecm/papers/tunetip.html
http://www.diy-efi.org/gmecm/papers/tunetip.html
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Joined: Jul 2004
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From: Fort Wayne, Indiana
Originally Posted by sandrock
Shot an email off to GMTuners this morning. Here'* hoping they can help me out 
On another note, I got 2 tables done last night...low and high octance spark advance. Maps look way different than the S2 maps did.
On another note, I got 2 tables done last night...low and high octance spark advance. Maps look way different than the S2 maps did.
Let me know via email or PM if you need anything else.
-ryan
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From: Fort Wayne, Indiana
Originally Posted by sandrock
Excellent!
But HP Tuner won't recognize it. I need the text output file for it. Guess I shoulda said that from the beginning
But HP Tuner won't recognize it. I need the text output file for it. Guess I shoulda said that from the beginning
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From: burb of detroit. 2 miles north of 8 mile Rd.
Originally Posted by Darth Fiero
Originally Posted by sandrock
Excellent!
But HP Tuner won't recognize it. I need the text output file for it. Guess I shoulda said that from the beginning
But HP Tuner won't recognize it. I need the text output file for it. Guess I shoulda said that from the beginning
Thread Starter
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From: In your garage, swipin' da lug nutz
I'll let you know in a few days. It'* gonna take a while for me to manually input the numbers into the tables.
Funny thing...I started on the MAF table today (taking it from the '93 since I still have the Genny 2 on the top), and I noticed something. The curve for it was near identical to the '97 stock L67 table...just had to shift it backwards by a hair. Putting the graphs side-by-side, you couldn't tell the difference between them.
Gotta work on the fuel injector tables next, then those shift points. I already noticed the vss reluctor was off, which was, no doubt, messing with the shift points.
Got an appointment in Orlando tomorrow, and I will be making a JY run while I am that close. Also gotta see Marik and drop off his engine stand
Funny thing...I started on the MAF table today (taking it from the '93 since I still have the Genny 2 on the top), and I noticed something. The curve for it was near identical to the '97 stock L67 table...just had to shift it backwards by a hair. Putting the graphs side-by-side, you couldn't tell the difference between them.
Gotta work on the fuel injector tables next, then those shift points. I already noticed the vss reluctor was off, which was, no doubt, messing with the shift points.
Got an appointment in Orlando tomorrow, and I will be making a JY run while I am that close. Also gotta see Marik and drop off his engine stand
