What's up with midgrade gas?

If performance cars get premium gasoline and standard cars get regular fuel, why does midgrade exist? Because some situations call for fuel with octane between, depending on region of the country, 87 and 90.

Before grabbing that nozzle, Zachary J. Santner, senior specialist of quality at Sunoco, advises you to consult the owner’s manual. It will explain your vehicle’s …

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On the Mazda CX-30 turbo, 87-91 octane can be run and the knock sensor figures it out. Somewhat surprisingly, it affects hp more than torque, where hp drops from 250 to 227, but torque only drops from 320 ft-lb to 310.

Sure, it's not exactly a hot hatch for the track, but the point is that newer engines do indeed cope with varying grades.

Yeah, but which midgrade?

I saw this while passing through Kansas on a trip a few years ago (as you may have guessed by the price). I'm sure this is just a fancy blender pump that can mix different ratios of 87 and 91, but who needs 3 midgrades, with 1-point resolution? It amused me enough to take the picture.

On top of that, temperature and altitude play a huge part.

In reply to obsolete :

Yep, the mid-grade is blended. When I worked at QT years ago, most stores had 4 tanks under the parking lot. 2 of 87, 1 of 91, 1 of diesel. 89 was a blend of 87 and 91. 

z31maniac said:

In reply to obsolete :

Yep, the mid-grade is blended. When I worked at QT years ago, most stores had 4 tanks under the parking lot. 2 of 87, 1 of 91, 1 of diesel. 89 was a blend of 87 and 91. 

I was at a Sheetz last month and saw basically the same thing posted for the tanker drivers.  One 30k gal 87 tank, one 10k gal 87 tank, one 10k gal 93 tank, and a 10k gal diesel tank.  Three grades (plus diesel) at the pumps so either they mix it when it is going in or they just mix at the pump between the high and low to make the mid.

A few years back my island(and other parts of eastern NC) had a regular unleaded shortage. People didn't want to pay for premium so they were buying mid-grade. Being that mid-grade is a blend it was taking ages to pump out. Glad I own a bicycle

In reply to frenchyd :

There are ethanol blender pumps, but that's not what this is. The pump in the picture is only blending gasoline (<=10% ethanol).

Where I live buying "mid-grade" gasoline is a waste of money.  You can get 93 octane or 87 octane. To get 89 which is what mid-grade is around here you don't get a 50//50 mixture of 87 & 93 but something like  60/40 to get 89 but you pay more for it as the price is halfway between 87 & 93.  If I'm looking for something more than 87 I prefer to blend it myself by just buying the amount of each grade to get what I want. 

FYI: I can remember the days when there was only a 10 cent difference between each grade. Now it's something like 45-50 cents.  

My truck is tuned for 91, and on 87 there's a huge drop off in power. But 89 seems to satisfy the knock sensors, and saves me some bucks over 91

obsolete said:

In reply to frenchyd :

There are ethanol blender pumps, but that's not what this is. The pump in the picture is only blending gasoline (<=10% ethanol).

We have the same thing here. 87-88-89-91 non oxygenated and E85  The difference is the E10 is 87 E15 is E88 E10 89 is a blend of 87& 91 

  Then one pump has E45 and the other pump has E85 which varies in ethanol depending on the season.  Oh, forgot Diesel.   I guess they must have a hard time keeping the tanks straight. 
 

In reply to Peabody :

Too bad you don't have Flex fuel.  The computer does the tune depending on what it samples. 
  It's really fun when I run E85. To get the best mileage I have to really feather the throttle lightly. But once in a while  I just gotta smoke the tires.  You'd think at 75 I'd grow outta that. 

frenchyd said:

In reply to Peabody :

Too bad you don't have Flex fuel.  The computer does the tune depending on what it samples. 
  It's really fun when I run E85. To get the best mileage I have to really feather the throttle lightly. But once in a while  I just gotta smoke the tires.  You'd think at 75 I'd grow outta that. 

I keep telling my self I don't need to burry the throttle on my MB but then my inner 12 year old starts telling me how fun it is. I like my 12 year old self. 

obsolete said:

Yeah, but which midgrade?

 

I saw this while passing through Kansas on a trip a few years ago (as you may have guessed by the price). I'm sure this is just a fancy blender pump that can mix different ratios of 87 and 91, but who needs 3 midgrades, with 1-point resolution? It amused me enough to take the picture.

At $2.16 a gallon, to hell with midgrade. I'm gettin' the good stuff.

jimbbski said:

FYI: I can remember the days when there was only a 10 cent difference between each grade. Now it's something like 45-50 cents.  

Ha!  More like $1/gal around here (DMV)

E85 is more than $1 a gallon cheaper than 87 octane  and more than $2 a gallon cheaper than premium.   Yet the extra power it makes feels like 50 horsepower. 
     OK the "cost" is in miles per gallon.  Driving decently it only costs 2 miles per gallon. 
    That still costs less per mile than 87 octane. 
     The flex fuel option is the best option a person can get.  Typically it's about $100  and it saves me on average $10.00 per tank full 

In reply to frenchyd :

  this is one pump the other side has E30  instead of E85 

 Another pump has the E45 plus non oxygenated premium   The pumps with Diesel are on another island  

frenchyd said:

E85 is more than $1 a gallon cheaper than 87 octane  and more than $2 a gallon cheaper than premium.   Yet the extra power it makes feels like 50 horsepower. 
     OK the "cost" is in miles per gallon.  Driving decently it only costs 2 miles per gallon. 
    That still costs less per mile than 87 octane. 
     The flex fuel option is the best option a person can get.  Typically it's about $100  and it saves me on average $10.00 per tank full 

Depending on the vehicle and where you're located, that can definitely work out well.  E85 is unfortunately not as cheap (or even as available) everywhere, so in some locations the math doesn't work as well. 

In reply to rslifkin :

So what is the local price for E85?  
 I was very disappointed  when they raised it here from $2.59/9  to $2.79/9   But the website reports a few still at the old price and one over in Chanhassen at $2.39/9 
   If you'll tell me what city and state you are. n I'll go n the E85 website and tell you where the nearest station is. 

frenchyd said:

In reply to rslifkin :

So what is the local price for E85?  
 I was very disappointed  when they raised it here from $2.59/9  to $2.79/9   But the website reports a few still at the old price and one over in Chanhassen at $2.39/9 
   If you'll tell me what city and state you are. n I'll go n the E85 website and tell you where the nearest station is. 

Looks like E85 around here is in the $3.50 - $3.80 range.  So unfortunately not nearly as cheap as your area.  I don't keep track of the prices all that closely though, as there are only  a handful of stations that have E85 around here, so I don't drive past them all that frequently.  The stations they're spread out enough through the area that it's not hard to get, just have to go a bit out of your way at times. 

Thanks,   I searched from Minnesota to  the challenge site to see if it would be possible to drive my 1972 V12 using E85.  Twin gas tanks for a total of 24 gallons   Plus two spots where I'd have to buy an extra 10 gallons  and it's doable  

Has anyone read up on the differences between how Europe and America measure octane?  I read or saw something that said that 91 In Europe was the equivalent to 89 in the US. This got me thinking that most European cars (mine included) have a 91 minimum sticker on the gas filler door and it got me wondering if that is 91 European and my car could be running the 89 and not the 93 that I usually run.  

dean1484 said:

Has anyone read up on the differences between how Europe and America measure octane?  I read or saw something that said that 91 In Europe was the equivalent to 89 in the US. This got me thinking that most European cars (mine included) have a 91 minimum sticker on the gas filler door and it got me wondering if that is 91 European and my car could be running the 89 and not the 93 that I usually run.  

https://en.wikipedia.org/wiki/Octane_rating#Measurement_methods

If your car was built for the US market, the manufacturer will have accounted for the differences in measurements.

In reply to dean1484 :

MON VS RON.  MOST EUROPEANS USE research octane method ( RON )  America uses RON+ Mon divided by 2