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ATS 2.0T RWD FE3
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Discussion Starter #1
This is kind of late, but earlier this year I had my early 2013 get the detonation/spark plug replacement TSB and I *swear* after the PCM flash and spark plugs it felt like the car picked up a tremendous amount of torque, maybe 30ft/lbs worth.

anyone else experience the same or actually dyno?

figuring that only software was the difference between the 295 and 270ft/lb LTG I kind of hoped that this would happen with a PCM re-flash. I'm betting it now has the 295ft/lb torque Flash of the new cars.

yay free power?
 

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'13 ATS4 2.0T, Gone but will be missed, '13 SRX4 Performance
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What I noticed most was a boost of about 4 mpg after the update. I really didn't feel an increase in torque, but then I don't drive on the edge of disaster.
 

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ATS 2.0T gone, 17 Charger Scat Pack current
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My mileage went up after the update/plugs as well.

Averaged 20.1 for the longest time, without resetting it, it has climbed to 21 since the update.
 

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2013 ATS 2.0T RWD, DP, Intake, HPT, CC
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Supposedly the flash brought it to the 2014 calibration, so it should not have been making more power. If the colder plug reduced/eliminated knock retard then you would definitely be making more power than before. The difference is the car would be making rated power, rather than less than rated power prior to the recall.
My car stock on 93 octane would occasionally show 1 - 2* of KR. If your car saw 2* - 4*, that would cause the knock air mass table to reduce power.
 

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ATS 2.0T RWD FE3
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Discussion Starter #7
It could also be just a good clean set of plugs were getting better combustion.
This was more than just spark plugs, and we're talking about plus rated for 100K with < 20K or so.

If the colder plug reduced/eliminated knock retard then you would definitely be making more power than before. The difference is the car would be making rated power, rather than less than rated power prior to the recall.

the correction description for the program is as follows;

Dealers are to reprogram the Engine Control Module (ECM) with a revised spark control

calibration, install spark plugs with a colder heat range (required with the new calibration) and

place an update to the spark plug part number information located in the "Maintenance

Replacement Parts" found in Section 11 of the Owner Manual. GM will mall the Owner Manual

supplement to customers of record.
 

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2013 ATS 2.0T RWD, DP, Intake, HPT, CC
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IIRC, Diablo Mike looked at a post-TSB car and indicated timing at WOT was reduced 1* and that was the only change made to the ECM. I had it done, but they didn't touch my tune, so I can't verify it.
 

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2013 ATS Performance 2.0T M6, 2016 Mustang GT Performance Pack, M6
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IIRC, Diablo Mike looked at a post-TSB car and indicated timing at WOT was reduced 1* and that was the only change made to the ECM. I had it done, but they didn't touch my tune, so I can't verify it.
I'm guessing he is right but then if its also true that it includes the 2014 spec, how are people feeling big changes in performance if nothing changed in the ECM accept reducing advance at WOT.

I am confused and by that I mean more than the usual.
 

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There were more changes but the only thing that would affect WOT situations was the reduction of 1* of spark.

If you've seen a bunch of logs from these cars, stock or tuned, you'd see they have a tendency to knock, some quite a bit, reducing commanded timing is a good way to get rid of excessive spark knock, so if the engine was knocking with the old cal, and the driver feels its stronger with the new cal, its because the motor is happy with the reduced timing level and as a result making more power than when the knock sensors would step in on the old cal, as they tend to be overly aggressive.
 

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There were more changes but the only thing that would affect WOT situations was the reduction of 1* of spark.

If you've seen a bunch of logs from these cars, stock or tuned, you'd see they have a tendency to knock, some quite a bit, reducing commanded timing is a good way to get rid of excessive spark knock, so if the engine was knocking with the old cal, and the driver feels its stronger with the new cal, its because the motor is happy with the reduced timing level and as a result making more power than when the knock sensors would step in on the old cal, as they tend to be overly aggressive.
My question was regarding how several things in this thread tied together. So how does LESS timing cause a requirement for colder plugs?
 

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'requirement' is a heavy term, more so there so some tech doesn't half ass it and install the plugs and not the update or vice versa...
 

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My question was regarding how several things in this thread tied together. So how does LESS timing cause a requirement for colder plugs?
A colder plug can reduces the amount of knock, as can reducing timing. The colder plug doesn't cause the need for less timing; it's two different methods to achieve the goal of less knock.

The problem would KR goes beyond having timing pulled. When KR goes over 2*, it triggers a lower value in the knock air mass table, which than tells the car to reduce the air flow into engine which in turn reduces the amount of power the engine can make. 2.1* of KR can cause power to drop significantly. Without looking it up, a 5% - 10% reduction in air mass is a reasonable estimate.
 
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