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So what is everyone running in there IM are you running premium gas or just regular gasoline? I started out running regular then i wanted to see if i would get better MPG with going to premium. I really didn't see a big difference with the switch. What your Thoughts??
 

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Depends on your driving habits. On long haul driving I use 87 as I get no difference in mileage what so ever using a higher octane gas.

For beating the piss out of the car I feel like the ECU calibrates differently for 93 octane. I feel a bit more pep. Mileage actually goes down a little bit, but the car feels more responsive and faster when using 93 octane.
 

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Depends on your driving habits. On long haul driving I use 87 as I get no difference in mileage what so ever using a higher octane gas.

For beating the piss out of the car I feel like the ECU calibrates differently for 93 octane. I feel a bit more pep. Mileage actually goes down a little bit, but the car feels more responsive and faster when using 93 octane.
I think you either need a blind test or that ethanol addition you typically get in lower octane fuels is making your experience different.
 

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I'll have the car on a DYNO soon. Will do an 87 Octane pull, 93 Octane pull, and a 93 octane pull on the OVTUNE ECU upgrade when it is available. They are working on a bench tune now for our cars.
 

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I'll have the car on a DYNO soon. Will do an 87 Octane pull, 93 Octane pull, and a 93 octane pull on the OVTUNE ECU upgrade when it is available. They are working on a bench tune now for our cars.

With the tune they are proposing we would need to use a higher octane.


Normally though, a higher octane does nothing for the car.
 

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So what is everyone running in there IM are you running premium gas or just regular gasoline? I started out running regular then i wanted to see if i would get better MPG with going to premium. I really didn't see a big difference with the switch. What your Thoughts??
Some light reading for ya:

http://www.kbb.com/car-advice/articles/premium-gas-when-and-why/

https://www.consumer.ftc.gov/articles/0210-paying-premium-high-octane-gasoline

http://www.scientificamerican.com/article/fact-or-fiction-premium-g/

Basically our car comes tuned from the factory for a certain octane of gas. Now heavy modifications or older engines may benefit from an octane boost, but other than that paying more just empties your wallet faster.
 

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With the tune they are proposing we would need to use a higher octane.
Duh... ?


Normally though, a higher octane does nothing for the car.
Normally, but the ECU does calibrate constantly for what fuel is in the car. It's all good. Like I said I plan to DYNO the car. I'll just let the data sheets do the speaking.
 

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With the tune they are proposing we would need to use a higher octane.
Duh... ?


Normally though, a higher octane does nothing for the car.
Normally, but the ECU does calibrate constantly for what fuel is in the car. It's all good. Like I said I plan to DYNO the car. I'll just let the data sheets do the speaking.
Interested to see you results but every resource states that using a higher octane alone does nothing for power gains.

Now combined with modifications and an engine tune, sometimes it becomes beneficial.
 

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I mean.. we have to understand with todays vehicles, doing something like an air intake doesn't yield any gains until the computer is tuned for it. The ecu will constantly make adjustments to maintain certain oem parameters so even throwing higher octane gas in isn't going to do anything.
 

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I mean.. we have to understand with todays vehicles, doing something like an air intake doesn't yield any gains until the computer is tuned for it. The ecu will constantly make adjustments to maintain certain oem parameters so even throwing higher octane gas in isn't going to do anything.
Very true, most people don't know that but when they hear the intake while driving that's apparently good enough for them, makes them feel like it makes a difference. Also for some i noticed it's purely engine bay blin
 

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Mods
Exhaust resonator delete
Intake Snorkel and and resonator delete with the fog light plate removed

Location Houston, Texas
Fuel 93 Octane Chevron or Shell
MPG 23 to 26

I feel at 5,000 rpm to redline it might make a difference, and in Houston it is Hot and Humid.
For cost 14 gallon tank 30 cent difference between the two = $4.20 each fill up
 

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Very true, most people don't know that but when they hear the intake while driving that's apparently good enough for them, makes them feel like it makes a difference. Also for some i noticed it's purely engine bay blin
Lol people hear the noise and fool themselves into "feeling" that the cars faster and what not. A lot of them just do it for engine bling and to say their "building" their car. Heck, a lot of people know that none of these things actually make a difference until you tune for it but still won't do it.
 

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Lol people hear the noise and fool themselves into "feeling" that the cars faster and what not. A lot of them just do it for engine bling and to say their "building" their car. Heck, a lot of people know that none of these things actually make a difference until you tune for it but still won't do it.
Some slight gains can be had by theses mods, but until you are able to mess with the ECU it is really limited.
 

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http://www.superstreetonline.com/how-to/engine/epcp-1007-2010-volkwagen-jetta-proven/

2010 Volkswagen Jetta 2.5L
Does higher octane fuel make a difference on all vehicles? It did in this case. Because of VW's advanced electronics and highly adaptive engine management, the Jetta 2.5L has an elastic response to a changes in octane levels. Once we put in the 87 octane, we could feel the drop in performance-less responsive, less peppy, and overall just different. The engine instantly detected the reduced octane levels and adapted for standard performance. This analysis was based on more than 1,200 miles of driving over a week.

Base 87 Octane
Temperature: 66° F
Humidity:15% Peak Power: 133 hp @ 5976 rpm
Peak Torque: 134 lb-ft @ 3444 rpm

Test 1
Performance
Peak power: 138 hp @ 5908 rpm
Peak torque: 146 lb-ft @ 4060 rpm
Peak power gain: 7 hp @ 5790 rpm
Peak torque gain: 13 lb-ft @ 4150 rpm
Temperature: 67° F
Humidity: 13%

Pros
• Increase of 1-2 mpg
• Increased throttle response and smoother power transitions
• Reduce risk of knocking or pinging
• Reduce risk of horsepower loss from heat soak
Cons
• $0.20 per gallon price premium
Test Notes
We took the Jetta to a gas station about a mile away from the dyno facility and filled it up with 13.74 gallons of 91 octane gasoline. We then drove the vehicle for 25 miles to give the vehicle a chance to adapt to the octane increase and make sure there was no 87 octane left in the lines.

Test 2
Performance
Peak power: 145 hp @ 5862 rpm
Peak torque: 148 lb-ft @ 4391 rpm
Peak power gain: 8 hp @ 5744 rpm
Peak torque gain: 9 lb-ft @ 4798 rpm
Temperature: 86° F
Humidity: 29%
 

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2010 Volkswagen Jetta - Proven - European Car Magazine

2010 Volkswagen Jetta 2.5L
Does higher octane fuel make a difference on all vehicles? It did in this case. Because of VW's advanced electronics and highly adaptive engine management, the Jetta 2.5L has an elastic response to a changes in octane levels. Once we put in the 87 octane, we could feel the drop in performance-less responsive, less peppy, and overall just different. The engine instantly detected the reduced octane levels and adapted for standard performance. This analysis was based on more than 1,200 miles of driving over a week.

Base 87 Octane
Temperature: 66° F
Humidity:15% Peak Power: 133 hp @ 5976 rpm
Peak Torque: 134 lb-ft @ 3444 rpm

Test 1
Performance
Peak power: 138 hp @ 5908 rpm
Peak torque: 146 lb-ft @ 4060 rpm
Peak power gain: 7 hp @ 5790 rpm
Peak torque gain: 13 lb-ft @ 4150 rpm
Temperature: 67° F
Humidity: 13%

Pros
• Increase of 1-2 mpg
• Increased throttle response and smoother power transitions
• Reduce risk of knocking or pinging
• Reduce risk of horsepower loss from heat soak
Cons
• $0.20 per gallon price premium
Test Notes
We took the Jetta to a gas station about a mile away from the dyno facility and filled it up with 13.74 gallons of 91 octane gasoline. We then drove the vehicle for 25 miles to give the vehicle a chance to adapt to the octane increase and make sure there was no 87 octane left in the lines.

Test 2
Performance
Peak power: 145 hp @ 5862 rpm
Peak torque: 148 lb-ft @ 4391 rpm
Peak power gain: 8 hp @ 5744 rpm
Peak torque gain: 9 lb-ft @ 4798 rpm
Temperature: 86° F
Humidity: 29%

Variables and no control.

You need to test multiple fuel sources to establish a true variance, ideally in similar conditions (not displayed).

Atmospheric pressure isn't even mentioned.
 

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A lot of variables weren't mentioned, or even taken down. Temperatures off the bat were different. All of these things need to be taken into consideration. Temp, elevation, were the gas came from before and after, the list goes on. You have to try to maintain consistent variables to compare the two.
 

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when I 1st purchased my IM in September 2015, its only 15 months old. on a fill up I would get 344mpg now I'm only getting 260mpg. I also notice that I don't even get 30mpg on the freeway. I use to get close to 40mpg. can anyone help with this problem. I don't want to touch anything due to the warrenty
 
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