i can’t be the only one who runs regular in a GT right?

[ScottsGT]

87 all the time unless the temps outside get in the upper 90's. Seems to run better on 92 during the worst part of the summer. Daily commuter, about 100 miles a day to work and back.

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[69mach1-395]

@ EBM
Well here it was about 20 cents per gallon different from mid grade and with higher octane. I might try it and see how it goes...
Anybody here using E15/Unl 88?

 

[ShadesOfBloo]

Interesting thread. I have always used branded gas/oil company names for the detergents versus the usually cheaper box store locations.

Same here, ever since I realized that additives vary by brand, not by octane.

 

[Dave2013M3]

HIgher elevation requires less octane as their is less oxygen in the atmosphere at altitude

Same here, ever since I realized that additives vary by brand, not by octane.

Especially here in Cali. All our fuel comes from the same refineries regardless of brands.

 

[ShadesOfBloo]

Higher elevation requires less octane...

I saw that firsthand on a trip to New Mexico in 2011. I remembered that their premium gas was 91 octane - except at Cloudcroft where it was 89 - and I was worried about how my Evo would run on NM gas.

Then I realized that a NM mountain pass was that car's happy place.
Not an autocross course... Not a highway...
Put it at 7,000ft of elevation, feed it 91 octane and lots of curves. Wheee!!!

 

[69mach1-395]

Yes, higher elevation requires less octane but...not a word about this in the owner's manual IIRC. It states 87 min, regardless.

 

[331GT]

one thing i noticed just yesterday was how much dirtier my exhaust tips are after using non-e85 for the last maybe 12 tanks or so. im assuming just much more carbon coming out than when i was e85 only most of the summer. i kind of liked the smell of e85 as well.

anyone know which is easier on cats, e85 or regular 87-93? based on the amount of carbon coming out id guess e85 would clog them less quickly but not sure if that's accurate.

 

[analogman]

FWIW, there are videos and tests out there comparing 87 vs 93 octane in the 5.0 engine, like this one -



My own personal experiences, after owning the car for 6 years, I've run both 87 and 93 octane. My seat-of-pants butt-dyno can't feel the difference. In normal street driving, I've never felt any difference in power, knocking, pulling timing, or anything else when running 87 regular.

Dyno runs suggest losing a handful of hp on regular. Maybe 10-15 ish? That's around 3% of the maximum output, and much less at 'normal' rpm's and street driving. My butt isn't sensitive enough to detect a 3-ish% difference.

I suspect if someone is tracking the car, or living at high altitudes or in high temperatures, there might be a discernible but not significant difference. I personally use regular in cold weather and premium in the summer, when higher temperatures might make a difference. But I've never felt any even then.

I hear all the arguments about 'buying a $40 or $50k car and then being worried about saving a few bucks on gas. They're true. If a few bucks on a fill-up makes the difference between being able to afford the car or not, then there are bigger issues. But regardless of how few the dollars might be, if the car doesn't need them, it's still flushing money down the drain.

Your mileage may vary.

 

[Dave2013M3]

FWIW, there are videos and tests out there comparing 87 vs 93 octane in the 5.0 engine, like this one -



My own personal experiences, after owning the car for 6 years, I've run both 87 and 93 octane. My seat-of-pants butt-dyno can't feel the difference. In normal street driving, I've never felt any difference in power, knocking, pulling timing, or anything else when running 87 regular.

Dyno runs suggest losing a handful of hp on regular. Maybe 10-15 ish? That's around 3% of the maximum output, and much less at 'normal' rpm's and street driving. My butt isn't sensitive enough to detect a 3-ish% difference.

I suspect if someone is tracking the car, or living at high altitudes or in high temperatures, there might be a discernible but not significant difference. I personally use regular in cold weather and premium in the summer, when higher temperatures might make a difference. But I've never felt any even then.

I hear all the arguments about 'buying a $40 or $50k car and then being worried about saving a few bucks on gas. They're true. If a few bucks on a fill-up makes the difference between being able to afford the car or not, then there are bigger issues. But regardless of how few the dollars might be, if the car doesn't need them, it's still flushing money down the drain.

Your mileage may vary.

To be frank 10-15rwhp isn't just a handful to me...we mod with an intake and tune to get 20rwhp we spend money on. Its your car do as you like...for me the $3.30 per gallon is a non issue for me. If a few bucks per fill up mean you can afford the car or not than you shouldn't own this car. Especially a car that gets the horrendous mileage that these cars do.

As far as high altitude you don't need that much octane, octane requirements drop at altitude.

BTW, the video is nonsense. There in no dyno runs no back to back runs or anything. Not impugning you, just for me the video is nonsense.

 

[velocityblue5.0]

Or, I can easily afford the 50k car, but I would like to put as much in my Roth as possible as well as into my savings, so yes, a few bucks here and there can add up, when running 87 which does nothing detrimental whatsoever to my 5.0.

 

[sk47]

To be frank 10-15rwhp isn't just a handful to me...we mod with an intake and tune to get 20rwhp we spend money on. Its your car do as you like...for me the $3.30 per gallon is a non issue for me. If a few bucks per fill up mean you can afford the car or not than you shouldn't own this car. Especially a car that gets the horrendous mileage that these cars do.

As far as high altitude you don't need that much octane, octane requirements drop at altitude.

BTW, the video is nonsense. There in no dyno runs no back to back runs or anything. Not impugning you, just for me the video is nonsense.

Hello; I get you point clearly. Let me illustrate another point. That being money works in the mind off of people in strange ways. I have a buddy. We both wanted a Porsche Cayman. I was shopping for a base Cayman because I knew it would have plenty of performance for driving on public streets, so why spend the extra money to get a Cayman S.
My buddy wanted and got the Cayman S. He paid more for it. It was a used model to be sure. Thing is he drives like the grandpa he actually is. He will only use a fraction of the performance of the car. The base Cayman would have been several times faster than he would have ever used, but he had to have the S model.

I used to do the work on his cars. He was looking at a used Toyota MR2. He brought it around for me to check out. I drove it around some, pushed it a bit and gave it a thumbs up. I fixed the electric power steering and a few other small things. Many years later he told me the test drive we went on with me driving was the hardest the car had ever been pushed. I had not driven it close to the limit, but closer than he had ever driven it.

This buddy likes the idea of having a performance car even if he never pushes one hard.

 

[m3incorp]

There are a lot of people like your buddy. Many relate it to I pay x amount of dollars over another that cost less, so it has to be the best for me. I know people that buy Cup2 tires and never drive the car over 50 mph and definitely not on a track......but they have been told the Cup2 is the best performance tire money can buy.

Hello; I get you point clearly. Let me illustrate another point. That being money works in the mind off of people in strange ways. I have a buddy. We both wanted a Porsche Cayman. I was shopping for a base Cayman because I knew it would have plenty of performance for driving on public streets, so why spend the extra money to get a Cayman S.
My buddy wanted and got the Cayman S. He paid more for it. It was a used model to be sure. Thing is he drives like the grandpa he actually is. He will only use a fraction of the performance of the car. The base Cayman would have been several times faster than he would have ever used, but he had to have the S model.

I used to do the work on his cars. He was looking at a used Toyota MR2. He brought it around for me to check out. I drove it around some, pushed it a bit and gave it a thumbs up. I fixed the electric power steering and a few other small things. Many years later he told me the test drive we went on with me driving was the hardest the car had ever been pushed. I had not driven it close to the limit, but closer than he had ever driven it.

This buddy likes the idea of having a performance car even if he never pushes one hard.

 

[Dave2013M3]

Or, I can easily afford the 50k car, but I would like to put as much in my Roth as possible as well as into my savings, so yes, a few bucks here and there can add up, when running 87 which does nothing detrimental whatsoever to my 5.0.

Sorry man, thats laughable. Bringing up a Roth IRA and paying $3.20 per tankful more in the same breath is asinine. Once you get past the fact that a new Mustang has to be one of the worse investment decisions you can ever make. You would be better off just not getting a latte at Starbucks once a month.

 

[velocityblue5.0]

Sorry man, thats laughable. Bringing up a Roth IRA and paying $3.20 per tankful more in the same breath is asinine. Once you get past the fact that a new Mustang has to be one of the worse investment decisions you can ever make. You would be better off just not getting a latte at Starbucks once a month.

Good thing I don’t drink Starbucks, right? How about rather than judge how other people spend their money and save for their retirement, you worry about yourself? Thread was made as a joke, and clearly some people are way too invested and take too much offense to how other people live their lives. Kind of pathetic, honestly. Mods should just lock this thread already.

 

[food_fanaticz]

lmao I sure as hell didn't buy my Mustang because of some investment decision. And who cares how someone wants to spend or save their money. If someone want to spend a little more to fill up with 93 or save a little and use 87 who cares. You do you and screw everyone else. I've just been lurking but had to comment cuz this thread is getting ridiculous lol

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