can we put LS1 MAF on LT1?
11-26-2012, 06:51 PM
#21
I did rape PE table with stock MAF on this tune pretty successfully, Holds a flat WOT A/FR on dyno. Just trying to get a little more tune in MAF areas.
Starting to think - just save my money and tweak the tune a little longer as is. I only HAVE to tune again in the spring because some alterations are coming this winter.
11-26-2012, 09:35 PM
#22
If memory recalls LT1 Hz range is 11,200??
What Hz you hitting the 512 limit? Doesn't matter what tube you install, the code is still only going to show 511.99, Hell I have a 4.5 inlet tube on my whipple setup. If you scale the tune completely (which is not that hard, but if you haven't done it before it gets complicated.
For example I usually do 50% scaled tunes, basically you report half the fuel the engine gets and half the air. So instead of having a 512 limit you have a 1024 limit. The table will still max out at 512 but that is really 1024 at point. So on setup like yours depending on what RPM your maxing it out at you may only see 300 g/sec of airflow (which is really 600g/sec)
Hope that makes sense.
I don't really care of SD on GM ECU's's the IAT plays too much a role in AFR. Aftermarket its a different story.
What Hz you hitting the 512 limit? Doesn't matter what tube you install, the code is still only going to show 511.99, Hell I have a 4.5 inlet tube on my whipple setup. If you scale the tune completely (which is not that hard, but if you haven't done it before it gets complicated.
For example I usually do 50% scaled tunes, basically you report half the fuel the engine gets and half the air. So instead of having a 512 limit you have a 1024 limit. The table will still max out at 512 but that is really 1024 at point. So on setup like yours depending on what RPM your maxing it out at you may only see 300 g/sec of airflow (which is really 600g/sec)
Hope that makes sense.
I don't really care of SD on GM ECU's's the IAT plays too much a role in AFR. Aftermarket its a different story.
11-27-2012, 12:07 PM
#23
T/A KID - thanks, I think I get it.
I'm on 2 bar so my MAP referenced tables are already scaled 50%
I could try what you suggested.
I don't want SD on my GM ECU street car either, hearing all the driving issues that need constant tuning.
on MAF, just WOT/PE needs tweaking due to the maxxed AFG/S reading. not that hard to work around.
Thanks
I'm on 2 bar so my MAP referenced tables are already scaled 50%
I could try what you suggested.
I don't want SD on my GM ECU street car either, hearing all the driving issues that need constant tuning.
on MAF, just WOT/PE needs tweaking due to the maxxed AFG/S reading. not that hard to work around.
Thanks
Then you have the LS6 MAF 
01-01-2013, 09:07 AM
#26
T/A KID - looking at dyno data logs, my afgs max out when MAP is into boost - no rpm or power logic - just open the throttle 100%, if MAP is into boost, I'm right at or maxed afgs. I can get pretty close to full boost without maxed afgs, until TPS = 100%
I have Tunercat/Datamaster and do not have a Hz reading - only the afgs.
Here is a shot of my MAF calibration stables - please reply with what your 50% scaled table would look like. I scale Hz 50%, the grams - or both?
Actually I only see these particular tables reference air flow - everything else in my tuning tables equates to MAP, RPM, TPS, etc - seems like these maf sensor calibration tables (and VE of course, which is %VE vs RPM vs MAP) are the only place my ECM looks at airflow.....
I understand fuel will need to be 50% also from our previous conversation.
Cut my MAF calibrations and injector rating 50% and my data logs should read 250 afgs when I'm actually flowing 500? Then I can use my MAF tables to dial in my a/f much further since it may not max out?
I have Tunercat/Datamaster and do not have a Hz reading - only the afgs.
Here is a shot of my MAF calibration stables - please reply with what your 50% scaled table would look like. I scale Hz 50%, the grams - or both?
Actually I only see these particular tables reference air flow - everything else in my tuning tables equates to MAP, RPM, TPS, etc - seems like these maf sensor calibration tables (and VE of course, which is %VE vs RPM vs MAP) are the only place my ECM looks at airflow.....
I understand fuel will need to be 50% also from our previous conversation.
Cut my MAF calibrations and injector rating 50% and my data logs should read 250 afgs when I'm actually flowing 500? Then I can use my MAF tables to dial in my a/f much further since it may not max out?
Last edited by chief455; 01-01-2013 at 10:08 AM.
01-01-2013, 09:31 PM
#27
Yep forgot Tunercats doesn't use a scanner (Which is beyond me)
At WOT what G/sec of airflow are you seeing and at what RPM?
If your running a Centri blower and barely maxing out G/sec I wouldn't worry about scaling the tune (with the current combo) and just add some fuel Via the PE table. Is that the right way, most would so no, but it works. Good thing with a Centri blower and this method is it works well b/c your boost is linear with RPM ulike a PD blower or Turbo.
THIS is the "correct" way to do it, Id say most don't (me included if your barely maxing it).
At WOT what G/sec of airflow are you seeing and at what RPM?
If your running a Centri blower and barely maxing out G/sec I wouldn't worry about scaling the tune (with the current combo) and just add some fuel Via the PE table. Is that the right way, most would so no, but it works. Good thing with a Centri blower and this method is it works well b/c your boost is linear with RPM ulike a PD blower or Turbo.
Cut my MAF calibrations and injector rating 50% and my data logs should read 250 afgs when I'm actually flowing 500? Then I can use my MAF tables to dial in my a/f much further since it may not max out?
01-02-2013, 10:01 PM
#28
Yep forgot Tunercats doesn't use a scanner (Which is beyond me)
At WOT what G/sec of airflow are you seeing and at what RPM?
Once 100% TPS or WOT is showing in Datamaster, my g/sec goes right to 511.99 regardless of RPM
If your running a Centri blower and barely maxing out G/sec I wouldn't worry about scaling the tune (with the current combo) and just add some fuel Via the PE table. Is that the right way, most would so no, but it works. Good thing with a Centri blower and this method is it works well b/c your boost is linear with RPM ulike a PD blower or Turbo.
My boost, even calling it Kpa in Datamaster - happens almost instantly when TPS hits 100% - from a low RPM hit to a 4500 RPM roll - when I hit WOT - max boost/maxxed out MAF happens.
THIS is the "correct" way to do it, Id say most don't (me included if your barely maxing it).
At WOT what G/sec of airflow are you seeing and at what RPM?
Once 100% TPS or WOT is showing in Datamaster, my g/sec goes right to 511.99 regardless of RPM
If your running a Centri blower and barely maxing out G/sec I wouldn't worry about scaling the tune (with the current combo) and just add some fuel Via the PE table. Is that the right way, most would so no, but it works. Good thing with a Centri blower and this method is it works well b/c your boost is linear with RPM ulike a PD blower or Turbo.
My boost, even calling it Kpa in Datamaster - happens almost instantly when TPS hits 100% - from a low RPM hit to a 4500 RPM roll - when I hit WOT - max boost/maxxed out MAF happens.
THIS is the "correct" way to do it, Id say most don't (me included if your barely maxing it).
thanks
01-02-2013, 10:14 PM
#29
leave the injector lb/hr rating constant alone?
Car should start, run the same, but I'll see 50% of airflow reported from what I currently see now in Datamaster? (511.99 will now be 256 etc.)
Then he can dyno tune a/fr with my MAF tables, since he can plug higher numbers than 256 into those tables for the frequency to relate to?
Am I even close?
01-02-2013, 10:51 PM
#30
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The injector size constant and injector lb/hr constant is the same thing. It needs to be halved as well as the MAF tables in order to scale the tune.
Really simple to do. Once you get that done you can use the MAF table to dial in fueling instead of raping the PE table.
Really simple to do. Once you get that done you can use the MAF table to dial in fueling instead of raping the PE table.
01-03-2013, 12:02 AM
#31
The injector size constant and injector lb/hr constant is the same thing. It needs to be halved as well as the MAF tables in order to scale the tune.
Really simple to do. Once you get that done you can use the MAF table to dial in fueling instead of raping the PE table.
Really simple to do. Once you get that done you can use the MAF table to dial in fueling instead of raping the PE table.
just half the 63 lb/hr constant? ONLY?
Once I half injector and all the MAF frequency table gm/sec entries - I can utilize gm/sec numbers like 400 (800g/sec actual) in the higher frequencies to establish where airflow REALLY maxes out? and dial in from there?
Seems like the boost tuning will likely be in the high frequency table where my current air flow goes out of sight under boost.
The rest of the low frequency MAF tune, runs great...probably leave it alone (halved) I'll just see it reported as half while logging data/tuning - correct?
01-03-2013, 12:22 AM
#32
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Correct the frequency won't change on the setup unless you physically change MAF sensors. This just gets you around maxing out the flow in the MAF table. You'll have to watch carefully though to not max out the frequency as well. If that happens then it is time for a LS3/7 MAF sensor in a 4" tube. That will basically give you more frequency headroom per flow. So basically you may have 11,000hz showing 400g/sec with the current MAF but with the card style it would only be 8,500hz for that same airflow. It scrunches up your low engine speed air flows but that's part of making power, compromise.
01-03-2013, 05:36 PM
#33
Correct the frequency won't change on the setup unless you physically change MAF sensors. This just gets you around maxing out the flow in the MAF table. You'll have to watch carefully though to not max out the frequency as well. If that happens then it is time for a LS3/7 MAF sensor in a 4" tube. That will basically give you more frequency headroom per flow. So basically you may have 11,000hz showing 400g/sec with the current MAF but with the card style it would only be 8,500hz for that same airflow. It scrunches up your low engine speed air flows but that's part of making power, compromise.
The data I've supplied in this thread thus far is based on logging my current stock LT1 sensor/tune.
Once I install the 4" unit, I figured I'd be scaling the tables as you guys have explained.
In the picture posted above #26 are the tables for MAF calibration in my 95 OBD1 ECM.
I don't see frequencies anywhere in my logging software (Datamaster).
Will this cause tuning issues - since I'll see gm/sec airflow reported, but have now idea at which frequency table it really is?
I was thinking when I see airflow reported, reference the corresponding frequency table and tweak the gm/sec values +/- to dial in fueling = wrong?
01-04-2013, 06:34 AM
#34
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That is exactly what I have for the car - an LPE 100mm sensor.
The data I've supplied in this thread thus far is based on logging my current stock LT1 sensor/tune.
Once I install the 4" unit, I figured I'd be scaling the tables as you guys have explained.
In the picture posted above #26 are the tables for MAF calibration in my 95 OBD1 ECM.
I don't see frequencies anywhere in my logging software (Datamaster).
Will this cause tuning issues - since I'll see gm/sec airflow reported, but have now idea at which frequency table it really is?
I was thinking when I see airflow reported, reference the corresponding frequency table and tweak the gm/sec values +/- to dial in fueling = wrong?
The data I've supplied in this thread thus far is based on logging my current stock LT1 sensor/tune.
Once I install the 4" unit, I figured I'd be scaling the tables as you guys have explained.
In the picture posted above #26 are the tables for MAF calibration in my 95 OBD1 ECM.
I don't see frequencies anywhere in my logging software (Datamaster).
Will this cause tuning issues - since I'll see gm/sec airflow reported, but have now idea at which frequency table it really is?
I was thinking when I see airflow reported, reference the corresponding frequency table and tweak the gm/sec values +/- to dial in fueling = wrong?
I recommend using HPTuners with a vortec truck tune file to adjust the MAF transfer curve. Having all of your 5 MAF tables combined into one table to smooth and view makes dialing in the MAF table that much easier!
01-04-2013, 07:06 AM
#35
The second injector flow rate constant you see is used for the Corvette's gas mileage display. Put 48 lb injectors in a Vette, and don't change that one too and it will show your gas mileage doubling. :-)
A decent scan tool will also display MAF frequency.
There is a frequency limitation in the PCM calibration that can be raised also, not just the grams per second limit.
If you buy the .tdf editor from Tunercat, and know how, you can make it display it as one long table. Also add other parameters, if you have a copy of the factory calibration listing. There are a few copies floating around.
Who annointed the PE table, and made it sacred? So, you "rape" all these other tables, so the PE Vs RPM tables looks like you think it should? I ran this by one of the GM Calibrators (would be called a "tuner" here) I know, and he said it made no sense to him either. Not trying to offend anybody, just don't get it.
Happy New Year!
A decent scan tool will also display MAF frequency.
There is a frequency limitation in the PCM calibration that can be raised also, not just the grams per second limit.
If you buy the .tdf editor from Tunercat, and know how, you can make it display it as one long table. Also add other parameters, if you have a copy of the factory calibration listing. There are a few copies floating around.
Who annointed the PE table, and made it sacred? So, you "rape" all these other tables, so the PE Vs RPM tables looks like you think it should? I ran this by one of the GM Calibrators (would be called a "tuner" here) I know, and he said it made no sense to him either. Not trying to offend anybody, just don't get it.
Happy New Year!
01-04-2013, 06:26 PM
#37
Thank you James!
The second injector flow rate constant you see is used for the Corvette's gas mileage display. Put 48 lb injectors in a Vette, and don't change that one too and it will show your gas mileage doubling. :-)
Thanks for explaining why that is there...
A decent scan tool will also display MAF frequency.
I might have access to that....
There is a frequency limitation in the PCM calibration that can be raised also, not just the grams per second limit.
With the basic $EE file - or would I need something else from Tunercat?
If you buy the .tdf editor from Tunercat, and know how, you can make it display it as one long table. Also add other parameters, if you have a copy of the factory calibration listing. There are a few copies floating around.
Perhaps MAF frequency is another parameter I could add...
Who annointed the PE table, and made it sacred? So, you "rape" all these other tables, so the PE Vs RPM tables looks like you think it should? I ran this by one of the GM Calibrators (would be called a "tuner" here) I know, and he said it made no sense to him either. Not trying to offend anybody, just don't get it.
Now that is just funny! I don't mind altering anything in the ECM to get it right - but when on the dyno, he sure wanted to utilize my MAF tables, and getting the PE table changes to result in desired air/fuel ratio was a bugger. He was scaling MAF by percent with a calculator, and results were pretty much as desired, but PE he just sort of 'winged' it after some math based attempts. It looks funny in the table, -20% here, + 15% there - but it works!Happy New Year!Same to you...
Thanks for explaining why that is there...
A decent scan tool will also display MAF frequency.
I might have access to that....
There is a frequency limitation in the PCM calibration that can be raised also, not just the grams per second limit.
With the basic $EE file - or would I need something else from Tunercat?
If you buy the .tdf editor from Tunercat, and know how, you can make it display it as one long table. Also add other parameters, if you have a copy of the factory calibration listing. There are a few copies floating around.
Perhaps MAF frequency is another parameter I could add...
Who annointed the PE table, and made it sacred? So, you "rape" all these other tables, so the PE Vs RPM tables looks like you think it should? I ran this by one of the GM Calibrators (would be called a "tuner" here) I know, and he said it made no sense to him either. Not trying to offend anybody, just don't get it.
Now that is just funny! I don't mind altering anything in the ECM to get it right - but when on the dyno, he sure wanted to utilize my MAF tables, and getting the PE table changes to result in desired air/fuel ratio was a bugger. He was scaling MAF by percent with a calculator, and results were pretty much as desired, but PE he just sort of 'winged' it after some math based attempts. It looks funny in the table, -20% here, + 15% there - but it works!Happy New Year!Same to you...
