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Discussion Starter #1
I had a MagnaCharger put in at the local shop, after doing several run efi logging, its knocking all over the spectrum. Low, high, starting soft or hard, punching it, manual shifting, you name it. I am pretty disappointed with this tune so I am taking the stock tune and like the CAM tune I did for my SS I am researching everything and doing it myself.

I just have to get the injector size, and high / low octane timing, pe enrichments. rest is pretty simple.
 

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May I quote you on that?
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This knocking was with the Magnuson tune?
 

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I hack cars.
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Magnacharger just finished revision B for the manual cars, ship your tuner back :)
 

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Discussion Starter #4
I am not using Magnusons tune, we got permission to use the shops version since they did not have an A4 tune they liked yet. I just talked to Magnuson and they gave me a few t/s'ing steps which I am doing now.
1. cutting away from the underneith of the hood parts that are touching, just barely but they were. done
2. take back to the shop and make sure the knock sensors are not lose. will do next week
3. remove 2 degrees until it stops from the high octane table ( dont think this is it since its knocking everywhere.
4. its the m/c and RMA it for a new one.

I just cut away the 3 spots it was touching and now taking out for some efi logging to see if it was that. fingers crossed.
 

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Well my fuel table seemed to be in backwards. Look there also. HP tuners is nice to have.
 

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JCMGTO said:
Well my fuel table seemed to be in backwards. Look there also. HP tuners is nice to have.
jcm what were your numbers after magna?
 

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Discussion Starter #7
I have LS1Edit for tuning not HP. From reading these EFILogs, I am thinking your right.
When sitting at 5.56 its fine, but when it drops to 5.2x its knocking. Obviously running lean, so now I have to find where in the IFR its doing that.
For the stranger thing, WHY, Magnuson says it should be at 5.25 g/s flow rate. If it was, this thing would burn through a piston in no time.
 

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How does your IFR table read? Having 5.2 will cause it to inject more fuel, if it likes 5.56. If possible copy your IFR table here. What is it at 0 VAC to 85 VAC
 

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Discussion Starter #9
LS1 Edit Dump of Table -- Fuel Injector Flow Rate

Filename = C:\GTO Tunes\gtoblown-1-updated tq reduction disabled.LS1

100 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 20
5.28 5.28 5.29 5.33 5.39 5.40 5.41 5.46 5.50 5.53 5.56 5.58 5.56 5.56 5.56 5.56 5.56

If thats to big of a PIA to read I copied it up to my site also.
Links below
Ls1Edit dump of IRF table
 

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Discussion Starter #10
Ahhh, ha. Just noticed while looking at the LS1edit screen/graph that the MAP pressure in Kpa.

Should that just be 5.56 across the board?
 

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No, cause the IFR is reading VAC. I record actual manifold vac. Easier to convert and read. But still the same. Anyway, looks like your table was correct or close. Or WOOOAAAA, wait a sec. LS1 displays the table different. As per HP tuners themselves. The IFR is read in VAC. So Cruise would be 85 and 0 would be WOT. To richen your car you would fill a smaller number into the cell on the table. Then the PCM thinks a smaller injector and actually sprays more to richen it up. While the larger number would cause it to spray less. And this is how I figured my table was backwards. I was leaning out up top. So I tweeked the table and got worse. Then I realized that it was backwards. In HP the table reads left to right. 0 VAC on the left and 85 VAC on the right.

0VAC
5.9 5.9 5.9 5.9 5.9 5.9 5.9 5.9 5.9 5.9 5.9 5.6 5.4 5.3 5.2 5.1 5

Hopefully that came out right.

So the way it was my LTFT's were Negative as heII and leaning out up top. I flipped it and had to do some tweeking but it seems to be getting better and stronger. But now I put my SPEC Stage 3 in and have to wait 400 miles to play again They want that many miles supposedly before thrashing it.

But the way the table was explained and the way it was put in, at 0VAC (WOT) the car or PCM was spraying less hence leaning it's self out. While at cruise and idle it was spraying more and running pig rich.

If you have heard a different explanation of the IFR table please let me know.
 

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Oh and I see by your table they also richened it up from mine too.
 

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Discussion Starter #13
You are correct, lowering the number lies to the pcm so it pushes more fuel. I would assume then these should be what Magnuson stated at 5.25, lower to push more fuel in the lean condition.
 
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