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‘19 Giulia Ti Sport Q4
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Discussion Starter #722
in reality if your car is not tuned to take advantage of the higher octane, its not going to do anything but make your wallet lighter .
Doesn’t the ECM in modern monitor knock to tune itself for fuel grade? I’d think the Giulia could certainly take advantage of higher-than-required (i.e. +91 rm/2) octane levels.
 

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Doesn’t the ECM in modern monitor knock to tune itself for fuel grade? I’d think the Giulia could certainly take advantage of higher-than-required (i.e. +91 rm/2) octane levels.
Most modern vehicles will retard timing to minimize knock but they cannot add in any more than is programmed into the tune ...so unless it's specifically tuned for high octane, everything else being equal ,using a higher octane than its designed for will not give you any benefit ...
 

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Discussion Starter #724
Most modern vehicles will retard timing to minimize knock but they cannot add in any more than is programmed into the tune ...so unless it's specifically tuned for high octane, everything else being equal ,using a higher octane than its designed for will not give you any benefit ...
I get it's not AI, but whether it advances or retards depends on the starting point, right, so if you put in 87 octane it'll retard, but it will then advance timing when it gets 93 octane back in the tank. The question would seem to be, then, how much advance/octane is the Giulia ECU tuned to take advantage of? Is 93 the max, or could it punch out more power at 98? At 104 octane? Any idea?
 

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I get it's not AI, but whether it advances or retards depends on the starting point, right, so if you put in 87 octane it'll retard, but it will then advance timing when it gets 93 octane back in the tank. The question would seem to be, then, how much advance/octane is the Giulia ECU tuned to take advantage of? Is 93 the max, or could it punch out more power at 98? At 104 octane? Any idea?
I see zero knk retard on 93 octane
 

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I get it's not AI, but whether it advances or retards depends on the starting point, right, so if you put in 87 octane it'll retard, but it will then advance timing when it gets 93 octane back in the tank. The question would seem to be, then, how much advance/octane is the Giulia ECU tuned to take advantage of? Is 93 the max, or could it punch out more power at 98? At 104 octane? Any idea?
The ECU has a specific timing table and can only retard when it senses knock..it can never advance past what its programmed for...so 104 would certainly be a waste...93 may even be on the edge of what it's capable of utilizing... and I say that only because 93 is not available in every state where the Giulia is sold...so I dont know exactly what its tuned for but I would assume somewhere around the 91 mark.


Its also worth noting that ignition timing is not a magic bullet...there is a point where there are diminishing returns even in the absence of knock.

I see zero knk retard on 93 octane
I think you would agree that's not at all suprising...that's probably at the top end of what a normal street tune can utilize

And I believe the curve is more important than the total timing ..even more so in a forced induction engine..
 

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Had some good launches this morning, pulled my best time with a 4% incline. I did put 3.5 gallons of e85 with my 93 fill-up. Running map2, not the new beta map2, but the og.

Thinking I can get into the 4.3-4.4 range with a flatter road... Not many safe places around my area unfortunately.

Pulled another 13.14 1/4 mile, also uphill, but trapped 101.27, instead of my previous 97.89mp . I think the uphill kept me at the same time :( Even on a flat road, doubtful I'll be able to break 13s with current setup... Time will tell.

99074
99075
 

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Discussion Starter #728
Had some good launches this morning, pulled my best time with a 4% incline. I did put 3.5 gallons of e85 with my 93 fill-up. Running map2, not the new beta map2, but the og.

Thinking I can get into the 4.3-4.4 range with a flatter road... Not many safe places around my are unfortunately.

Pulled another 13.14 1/4 mile, also uphill, but trapped 101.27, instead of my previous 97.89mp . I think the uphill kept me at the same time :( Even on a flat road, doubtful I'll be able to break 13s with current setup... Time will tell.

View attachment 99074 View attachment 99075
Nice and quick! I’m surprised a 4% incline is considered valid.
 

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I wonder how quickly a car's ECU can adapt to a higher octane, and how quietly it will return to a lower map when the engine encounters the usual lower octane. Maybe plenty of tolerance for this, but then, maybe not. I don't use them. When a bottle advertises ".... raises one point," I think it means .1 increase in the tank's octane, not increasing say from 91 to 92 octane. I am no expert on this. NV
 

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I wonder how quickly a car's ECU can adapt to a higher octane, and how quietly it will return to a lower map when the engine encounters the usual lower octane. Maybe plenty of tolerance for this, but then, maybe not. I don't use them. When a bottle advertises ".... raises one point," I think it means .1 increase in the tank's octane, not increasing say from 91 to 92 octane. I am no expert on this. NV
It can adapt basically instantaneously but will only adapt upwards so much as it is programmed for. Unfortunately on 93 octane i already see zero timing retard so thats not a good sign for being able to take advantage of higher octane.
 

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I wonder how quickly a car's ECU can adapt to a higher octane, and how quietly it will return to a lower map when the engine encounters the usual lower octane. Maybe plenty of tolerance for this, but then, maybe not. I don't use them. When a bottle advertises ".... raises one point," I think it means .1 increase in the tank's octane, not increasing say from 91 to 92 octane. I am no expert on this. NV
like running straight gas in a 2 stroke engine? I had a super fast Suzuki quadzilla that we put a few gallons of straight gas in one day and I just so happened to get into a police chase through every street in my neighborhood that night. 10 cars at one point. They obviously couldn’t catch me. But the straight gas eventually did as I was cruising thinking I got away and the engine seized. I was stalled trying to kick start when the k-9 came. Was maced while handcuffed. That would make CNN today lol. Good night. Released in an hour.
 

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like running straight gas in a 2 stroke engine? I had a super fast Suzuki quadzilla that we put a few gallons of straight gas in one day and I just so happened to get into a police chase through every street in my neighborhood that night. 10 cars at one point. They obviously couldn’t catch me. But the straight gas eventually did as I was cruising thinking I got away and the engine seized. I was stalled trying to kick start when the k-9 came. Was maced while handcuffed. That would make CNN today lol. Good night. Released in an hour.
Sounds like you know how to party.
 
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