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Just picked up my 04 Silver GTO saturday. This board was very helpful before I made my final decision. I decided to lease it since I have some questions about the residual value going forward. But, I will sure enjoy it for the next 3 years. She purrrrrs like a kitten.

Any thoughts on the use of high octane gas (premium) vs the standard 87 octane. It appears premium is not required but recommended. I would think you would have a slight drop off in performance but not noticeable. What is everyone's thoughts on which gas should be used.

What type of mileage is everyone getting? It won't stop me from putting my foot into it but just curious as what can be expected going forward.

Drive em fast and just remember to swerve!
 

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I don't have it with me, but I'm pretty sure the manual says "PREMIUM" and that mid or regular may be used, but not recommended.

I keep the dash display on the MPG setting, and generally get 14+ MPG. Previous tankful went 16.1. Not bad for the stop-and-crawl driving that I do to/from work.

Look at this this way... Generally Premium goes for about a dime more than regular a gallon. That's $1.80 if you fill up the tank from bone dry. Isn't the take off from just one light worth less than 2 bucks?


---Larry
 

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catchmeifucan said:
Just picked up my 04 Silver GTO saturday. This board was very helpful before I made my final decision. I decided to lease it since I have some questions about the residual value going forward. But, I will sure enjoy it for the next 3 years. She purrrrrs like a kitten.

Any thoughts on the use of high octane gas (premium) vs the standard 87 octane. It appears premium is not required but recommended. I would think you would have a slight drop off in performance but not noticeable. What is everyone's thoughts on which gas should be used.

What type of mileage is everyone getting? It won't stop me from putting my foot into it but just curious as what can be expected going forward.

Drive em fast and just remember to swerve!
You just spent 40k for a fast ass car, and you want to put 87 octane in it? Performance will suffer. If you use 87 octane usually your PCM will pull back timing to reduce pre detonation, in turn giving you car less performance and making it slow. I own an SRT-4 (no hating) and if you put 87 in it, the PCM senses it and starts pulling timing to reduce pre detonation and drops boost by like 5 lbs. for 10 cents more I would just stick with the premium, or you could use middle grade and then add some octane booster. Need to keep up the performance aspect of your car, in case I come up next to you! Good luck!
 

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Agreed, why use 87 octane. If you even open up your door for your gas cap...it's will even say on that "Premium Recommended!"

Give your car what it wants to drink...give it 93
 

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First, I agree you will lose performance. The performance you will lose is a function of speed and load. Generally speaking, the amount of spark retarded due to a lower grade fuel ( as low as 87 octane ) is very small at part throttle, and increases more significantly as the load increases. Even after the system has "learned down" form the 87 octane, mid-range and normal cruise speeds probably are not effected form reduced spark. However, any time you would "put your boot" into the throttle, with 87 octane you will lose performance. Wide open throttle is already a very low MPG load point so over-all fuel economy, would most likely not be effected, ( or would be effected so little as to be unnoticable) if you drive at a reasonable throttle. But all that being said, even 20 cents a gallon difference in price is only $3.60 a tank !!!!!

And you never know when some PESKY SRT4 might be lurking !!!!
 

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GTO TOO said:
First, I agree you will lose performance. The performance you will lose is a function of speed and load. Generally speaking, the amount of spark retarded due to a lower grade fuel ( as low as 87 octane ) is very small at part throttle, and increases more significantly as the load increases. Even after the system has "learned down" form the 87 octane, mid-range and normal cruise speeds probably are not effected form reduced spark. However, any time you would "put your boot" into the throttle, with 87 octane you will lose performance. Wide open throttle is already a very low MPG load point so over-all fuel economy, would most likely not be effected, ( or would be effected so little as to be unnoticable) if you drive at a reasonable throttle. But all that being said, even 20 cents a gallon difference in price is only $3.60 a tank !!!!!

And you never know when some PESKY SRT4 might be lurking !!!!
EXACTLY! I am very PESKY!!! But I have mad respect for the GTO....be sure if I roll up on ya, you are on 93 octane;0)
 

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So how is the GTO with gas??? With gas prices being ridiculously high, i am curious to know what the mpg the GTO gets. Over here in Los Wages(Las Vegas), gas is going for about 2.00 bucks a gallon.
 

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Tuxedo Mask said:
So how is the GTO with gas??? With gas prices being ridiculously high, i am curious to know what the mpg the GTO gets. Over here in Los Wages(Las Vegas), gas is going for about 2.00 bucks a gallon.
I get around 15-16MPG doing the stop-and-crawl to/from work, and got 22mpg on about a piece of open expressway the other day. Better than my 4wd Blazer (13mpg), not quite as good as my Grand National (17mpg) in the same drive conditions. Not stellar, but not horrible either - but hey, them 8 cylinders are thirsty!

---Larry
 

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I drive mine 2 times a week on Texas wide open country. At 70-75 I am often getting 27 or 28 miles to the gallon. I average about 21. But I drive on open road alot.
 

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MPG we are getting

We just made a trip from Indy to Milwaukee and doing 72 we were getting 28mpg on flat road (with 6 speed).

In stop and go stuff I shift from 1 to four and then four to six and we typically average about 22 around town.

The car is powerful enough to put into 6th gear at 30mph and don't touch the gas it will stay at 30 unless you hit a hill and the whole time you are getting about 35-37mpg.
 

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Gas mileage

I only avg 12 mi city and 16 highway, and im not even trying to redline it. the dealer has no reasonable answer. believe me when I say that I stay out of the throttle. @ $2 a gallon im a little worried. what's your take
 

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sorry not to much sympathy here were paying 2.30per gal for premium up here in the north country.get your wallet or gas card out you got to pay to play. ;)
 

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Crap..out here in the Soviet Socialist Republik of Kalifornia we can't even get 93 octane at the pump...so we get 91 octane, pay $2.30/gal for it, and smile the smile of the reamed...
 

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Gas prices always suck in Cali... thats because of all the extra formulation additives that are required because of the wonderful air quality on that side of the country. Extra additives... cost extra money.

Keep in mind as you talk about gas milage.... the auto trans get about 7 mpg less than the standard transmissions on the highway.

Use the octane that is stickered on the car... or recommended in the manual. Most cars these days can suffer through what ever you feed it... however, the cars fuel and engine management systems are programmed with certain fuel assumptions. Your emission sensors are also designed to operate in a certain environment. Those computors track a lot if info these days. You actually have a Black Box in those cars (most cars today do). If you get in an accident... they pull the computer and get all kinds of data.

Make sure that fuel use doens't cause any warrenty issues.
 

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Goerge I stand by what I posted. You will still pass emissions, you will lose preformance at wide open throttle. The black box does not log all data. It does log throttle. speed. brakes applied etc, for some amount of time before the "AIRBAG" went off. But the time frame for the data logged is fairly short. ANd it is logged only after an accident that fires the "BAG". What is logged pretains to how the vehicle was driven just before the "crash". It is not all inclusive of all the ECM data.

While I agree they are calibrated with assumptions ( I prefer recommendations) the engine will function with a 87 octane. The knock system will "learn" the spark down to a level for NO knock, so you loose high load preforance, but fuel control is not effected by 87 octane. The engines O2 sensors read oxygen or the lack thereof, many differnt fuels are used acrossed the USA and all still run stoich at closed loop. Stoich is not a set air/fuel ratio is is dependant on which fuel you have installed. Some have more oxygenates that others ( Calif Phase II for instance ). And many fuel modes are OPEN LOOP.
 

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GTO TOO said:
Goerge I stand by what I posted. You will still pass emissions, you will lose preformance at wide open throttle
Not sure what you mean by this... stand by what? I never contested any thing you said, nor did I even mention passing emisions, or performance. :confused Slow down and read the post before responding.


The black box does not log all data. It does log throttle. speed. brakes applied etc, for some amount of time before the "AIRBAG" went off
Actually there are several computers that log data of all aspects of performance. They track sensor readings from various emmision sensors, throtle position, and even top rpm and mph speeds (and much more). In the event of an acident they also measure G force of the vehicle. All this data can be acessed with dealer equipment or even the home version... Auto Tap.

the engine will function with a 87 octane
Isn't that what I said??

:cheers
 
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