# What Fuel Type ?



## OrlUberOffDriver (Oct 27, 2014)

Any of you fill up with whatever is cheapest, even if your vehicle requires premium?


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## Adieu (Feb 21, 2016)

Have Flexfuel, have diesel


The flexfuel isnt particularly particular (long as it ain't diesel), but the diesel is capricious as all hell (think unlabeled "premium diesel", since no such separate subclass for ULSD exists).... and only likes high-cetane Mobil, G&M, or Costco, the latter two abundantly doped with Howe's or Liquimoly


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## OrlUberOffDriver (Oct 27, 2014)

I chose to burn E-85 v premium but every 4-5 tank got to fill with premium. 
Mileage suffers with E-85 but is still worth it paying $2.159 v $3.089 today in Orlando.


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## Fauxknight (Aug 12, 2014)

...of course I fill up with whatever is cheapest. Usually I go with regular, but when diesel drops in price I top it off with that. My mechanic isn't very good at explaining why my car keeps having issues.



E85 burns hotter and will do more damage to the engine and seals. Usually the extra mpg from regular will make up the price difference. E85 isn't bad on its own, a vehicle designed to exclusively run E85 would actually do well. At 100-105 octane E85 has the potential to perform better than other fuels. The issue is flex fuel vehicles aren't designed that way and instead of getting increased power and mpg they generally take a loss of near 30% on mpg on top of running hotter. Just stick to the regular, most places water it down with a little corn anyways.

Side note, we had an Ethanol tanker crash on an underpass a couple years back. Caught fire and melted the concrete above it. Messed up traffic big time for a month, city paid big bucks to get a contactor to work 24/7 on the repairs. Nasty stuff...of course the kicker was he wasn't even allowed to be on that underpass with an ethanol tanker.

Unless you have a high performance car that requires it there isn't much point in using premium, particularly since the price difference from regular has been upped significantly recently.


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## UberDez (Mar 28, 2017)

Two of my cars require Premium however one of them I'll use Regular or Mid Grade in when working as it really doesn't matter if you're driving easy . My other car is flex fuel I've figured E85 gets me about 20% worse gas mileage so as long as E85 is over 20% less than Reqular I'll use it


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## Dude.Sweet. (Nov 15, 2016)

I always use premium, I have a v6 and don’t want the cheap stuff to ruin my engine. Dirty gas (low octane) will cause more corrosive build up over time.

If I had a 4 cyl I would probably go with the middle stuff.


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## Spork24 (Feb 5, 2018)

Dude.Sweet. said:


> I always use premium, I have a v6 and don't want the cheap stuff to ruin my engine. Dirty gas (low octane) will cause more corrosive build up over time.
> 
> If I had a 4 cyl I would probably go with the middle stuff.


wrong. where you get your gas is more important than what grade you get.


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## EcoboostMKS (Nov 6, 2015)

Dude.Sweet. said:


> I always use premium, I have a v6 and don't want the cheap stuff to ruin my engine. Dirty gas (low octane) will cause more corrosive build up over time.


Nothing about the statement is correct. Are you sure you know what octane is?

Unless your driving a high compression engine, you're wasting your money with higher octane gas. Put in whatever your owner's manual tells you to put in. That's what your car is tuned to drive on.


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## Sariandan (Feb 3, 2018)

Dude.Sweet. said:


> I always use premium, I have a v6 and don't want the cheap stuff to ruin my engine. Dirty gas (low octane) will cause more corrosive build up over time.
> 
> If I had a 4 cyl I would probably go with the middle stuff.


Octane is resistance to knock. Knock is the premature ignition of fuel under compression. You're pissing away money if you don't drive an engine that requires premium fuel. We used to have a drag strip, around here, that would allow the public to come in and race their cars. It really cut down on the street racing, as they now had an outlet to do this stuff legally, and quite a bit safer. But, I always laughed at the people that would line up at the gas station, down the street from the track, that sold 106 octane fuel. They swore it made the car faster.


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## bsliv (Mar 1, 2016)

Octane is a measure of its ignition point, not its energy capacity. A low octane rating will ignite easier than a high octane rating. Pre-ignition is bad for an engine. Pre-ignition sounds like marbles in a tin can. Generally, a high compression engine requires a high octane rating. But not always. My Mazda has a 13:1 compression ratio and it likes normal 87 octane. Others have tested a higher octane and it actually reduces its performance. Spend more money for less performance? No thanks.


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## EcoboostMKS (Nov 6, 2015)

Sariandan said:


> Octane is resistance to knock. Knock is the premature ignition of fuel under compression. You're pissing away money if you don't drive an engine that requires premium fuel. We used to have a drag strip, around here, that would allow the public to come in and race their cars. It really cut down on the street racing, as they now had an outlet to do this stuff legally, and quite a bit safer. But, I always laughed at the people that would line up at the gas station, down the street from the track, that sold 106 octane fuel. They swore it made the car faster.


Ironically, they're most likely hurting engine performance by putting in that high octane gas. You put in the fuel the your car was designed to consume for optimal performance. It's as simple as that.

Once you start modding and tuning, now that's a different story.


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## UberDez (Mar 28, 2017)

Dude.Sweet. said:


> I always use premium, I have a v6 and don't want the cheap stuff to ruin my engine. Dirty gas (low octane) will cause more corrosive build up over time.
> 
> If I had a 4 cyl I would probably go with the middle stuff.


Wow

Who taught you this ?


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## Mars Troll Number 4 (Oct 30, 2015)

You should really just use what is recommended for your car by the manufacturer.

They have little need to lie to you, but if Mercedes or BMW says your car needs premium you gotta run premium.

These are finely tunes machines engineered to run on Hi octane go juice. Using too low of an octane can cause knocking and that can cause extra engine damage over time.

My racing car is loaded down with custom mods and the engine get's really bad fuel economy because it is running so fast, and tuned for high speeds. It also NEEDS high Octane fuel.

However everything else i drive is fine with 15% or les ethanol..

EXCEPT my Harley trike which runs badly on ethanol added gasoline and needs Ethanol free gasoline or it just doesn't run properly. (i buy from Wawa)

So this poll really needs a "it depends on the car" option.


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## Fauxknight (Aug 12, 2014)

Mears Troll Number 4 said:


> However everything else i drive is fine with 15% or les ethanol.


I'm glad the stations around here max out at 10% in their normal gas. Still it's almost as useful as adding water to the fuel, you pretty much lose that 10% on the mpg backend. Might as well charge me 10% more and give me 100% pure gas, but that's not how the ecopolitics of ethanol work.


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## Signal Twenty (Jun 26, 2017)

Electric!


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## Fauxknight (Aug 12, 2014)

Signal Twenty said:


> Electric!


Sure, but with 2 conditions:

1. I can afford an electric vehicle with a near 300 mile range.

2. I can convince my condo association to add car chargers in the parking lot.


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## Signal Twenty (Jun 26, 2017)

I’ve got a much more affordable car. Sure it’s less range than a Tesla, but 110 miles is 110 miles. I only drive very part time, so I haven’t had any requests to go really far (~20miles). It works for me. 

Having a plethora of public chargers has definitely helped, too.


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## Fauxknight (Aug 12, 2014)

Signal Twenty said:


> I've got a much more affordable car. Sure it's less range than a Tesla, but 110 miles is 110 miles. I only drive very part time, so I haven't had any requests to go really far (~20miles). It works for me.
> 
> Having a plethora of public chargers has definitely helped, too.


I drive full time, any good day is more than 110 miles. I have had a few 50-60 mile in state requests and one 215 mile request.

Public chargers are few and far between here, and if I was cranking out a good day I'd hate to stop for awhile just to get a few more miles.

Electric vehicles are taking big steps in the right direction. The Model 3 could sate my range needs, but I still need better access to charging. Such will come with time if electric vehicles continue to become more popular. I'll eventually trade my condo for a house and that would give me at least on dedicated plug to use.


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