Spring build comes early
#241
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Let'* not forget I also changed the throttle body and MAF.
Think of it this way. The PCM needs to know how much air can enter the engine for each condition, ie, RPM, and load. This is the VE table, volumetric efficiency. This is a hard coded table and is the starting point for all calculations to setting the AFR, Air fuel ratio. The PCM can adjust this by -20 to +20. If you look at that one chart, the histogram shows how much the PCM has to adjust. These readings are very far form zero, zero is the aim point. By changing how much air can enter the engine (cam change, throttle body, porting heads, etc) the tables need to be changed. If this table is not set correctly then all calculations will be off.
Think of it this way. The PCM needs to know how much air can enter the engine for each condition, ie, RPM, and load. This is the VE table, volumetric efficiency. This is a hard coded table and is the starting point for all calculations to setting the AFR, Air fuel ratio. The PCM can adjust this by -20 to +20. If you look at that one chart, the histogram shows how much the PCM has to adjust. These readings are very far form zero, zero is the aim point. By changing how much air can enter the engine (cam change, throttle body, porting heads, etc) the tables need to be changed. If this table is not set correctly then all calculations will be off.
#242
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I'm curious, has anyone used the real time tuning for hp tuners? I would think if you had two people it could cut down on the time it takes for a good tune. One to drive, one to tune.
#246
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Real Time Tuning It is the first item on the list. Cost 2 credits for one vehicle.
#247
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#248
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By putting in the LS1 maf table you should help the tune. Definatley changed everything up for sure.
Real time tuning like Dan mentioned..and my understanding was...only V8'*.
Real time tuning like Dan mentioned..and my understanding was...only V8'*.
#249
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Was able to make a short VE run this morning. Slowly coming back in to shape.
I think I've got 2 or 3 more runs and it should be very close.
Edit.
Next run is way better, as you can see most but not all numbers are within the -5 to +5 range.
I think I've got 2 or 3 more runs and it should be very close.
Edit.
Next run is way better, as you can see most but not all numbers are within the -5 to +5 range.
#250
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After getting the VE tune to where I was happy, I scrapped out my MAF curve and started out with a stock LS1 curve, then went back to a stock PE table. The object here is to get the LTFT as close to zero -5 to +5.
Run number 2, I didn't even save the scan from run 1
As you can see, I was off a bit, numbers all over. After several tweaks of the MAF curve, I got it a bit closer.
A few more tweaks and a few more runs, and it'* even closer.
After 8 runs, I have it very close. I made one last tweak at the 5000hz and up range, that should bring that area down a bit more.
But all in all, I have it very close. The car feels stronger each time I go out. When working on the PE table I had some KR. Starting the tune I had a lot, like over 5*, as I got the MAF dialed in that dropped to 2.5*, but then I noticed my IC pump was turned off, oops. Turned that back on, added a little bit of fuel to the PE table, and no KR to speak of. I get a small spike here and there but mainly because I'm doing a rolling start. Once floored I have no KR. Ignore the wide band readings. I don't trust it. I'll be doing a free air calibration as soon as I can.
On my last run I was going 50mph and floored it. Trans down shifted and the tires broke loose. Wow.
Run number 2, I didn't even save the scan from run 1
As you can see, I was off a bit, numbers all over. After several tweaks of the MAF curve, I got it a bit closer.
A few more tweaks and a few more runs, and it'* even closer.
After 8 runs, I have it very close. I made one last tweak at the 5000hz and up range, that should bring that area down a bit more.
But all in all, I have it very close. The car feels stronger each time I go out. When working on the PE table I had some KR. Starting the tune I had a lot, like over 5*, as I got the MAF dialed in that dropped to 2.5*, but then I noticed my IC pump was turned off, oops. Turned that back on, added a little bit of fuel to the PE table, and no KR to speak of. I get a small spike here and there but mainly because I'm doing a rolling start. Once floored I have no KR. Ignore the wide band readings. I don't trust it. I'll be doing a free air calibration as soon as I can.
On my last run I was going 50mph and floored it. Trans down shifted and the tires broke loose. Wow.