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Author	Topic: Mixing Premium & Mid-Grade	Topic is locked Back to Topics

Pucelle Rookie Author Rochester Posts:33 Points:72,240 Joined:Jun 2002	Message Posted: Mar 24, 2012 7:39:27 PM Ignore Pucelle Report Abuse Do you mix premium and mid-grade (or regular since these days the spread is sooo wide) to get the best price and octane to get to 91? Or do you just get Premium most of the time and maybe the occasional mid-grade?

Pucelle

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Rochester

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Message Posted: Mar 24, 2012 7:39:27 PM

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Do you mix premium and mid-grade (or regular since these days the spread is sooo wide) to get the best price and octane to get to 91? Or do you just get Premium most of the time and maybe the occasional mid-grade?

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PatAZ Champion Author Tucson Posts:9,253 Points:122,460 Joined:May 2008	Message Posted: Jan 7, 2013 10:29:57 AM Ignore PatAZ Report Abuse Just regular in the Toyota, always premium in the BMW.
LauraLea5 All-Star Author Ontario Posts:779 Points:439,085 Joined:Mar 2011	Message Posted: Jan 7, 2013 6:30:14 AM Ignore LauraLea5 Report Abuse No
medic6133 Champion Author New York Posts:1,120 Points:218,215 Joined:May 2012	Message Posted: Jan 7, 2013 5:36:32 AM Ignore medic6133 Report Abuse Premium only.
dgsteven All-Star Author Los Angeles Posts:812 Points:209,825 Joined:Oct 2012	Message Posted: Jan 7, 2013 3:24:29 AM Ignore dgsteven Report Abuse no way
Pucelle Rookie Author Rochester Posts:33 Points:72,240 Joined:Jun 2002	Message Posted: Apr 12, 2012 1:07:57 PM Ignore Pucelle Report Abuse For those of you that didn't know, most cars that require "premium" gas actually require a minimum of 91 octane. Gas stations usually have 87, 89, and 93 for their gas with a spread of 10 cents between. Now a days that spread is higher, especially between Regular & Mid-grade that mixing Reg & Premium can be more cost effective than Mid & Premium depending on price/station. I have almost 18 gallons in my tank and so the 10+ cent spread is noticeable. I do know that for Top Tier gas stations, I can use 89 (my manual even states it) but there have been times when it has been cheaper to do my own mix of premium & regular than just mid grade since regular was 40-50 cents cheaper.
jimmy544 Champion Author Boston Posts:4,133 Points:655,805 Joined:Feb 2011	Message Posted: Apr 8, 2012 8:44:58 AM Ignore jimmy544 Report Abuse It is true that it is an uncommon situation but I have seen at least one station in Eastern Nevada that had diesel and reg gas and that was all. Also it was really expensive and the only station open for about 100 miles. That was in 2009 in January. I So it does happen. I think I have seen this a couple of other times too since then but that particular experience sticks in my mind because I was really low on gas because the station 100 miles before had been closed. Eastern Nevada even in January is pretty barren and desolate. Because this situation does happen occasionally the government mandates that all gasoline cars need to be able to run on regular gas without damage. It is true that some old cars from the 60's would likely not run well and might be damaged but cars from the late 70's on were supposed to be able to run on unleaded regular without damage. The engine will not develop max power if it needs premium to do so because the ignition system will retard as someone pointed out but this will not lead to damage because the damage comes from pre-ignition AKA knocking. It will just be down on power.
BobSassafrass Rookie Author Houston Posts:12 Points:5,595 Joined:Apr 2012	Message Posted: Apr 4, 2012 4:23:31 PM Ignore BobSassafrass Report Abuse The reason for using Premium is because high compression engines require it to prevent detonation. When you use 87 in these engines it detonates (knocks) then the engine compensates by retarding ignition timing. This is bad for the engine. The retarded ignition timing leads to less MPG as Sluggopyle said. But prolonged use can cause engine problems that will surely cost more than an extra 30 cents a gallon.
alphanyr Champion Author Connecticut Posts:4,850 Points:678,675 Joined:Apr 2011	Message Posted: Apr 3, 2012 7:16:22 PM Ignore alphanyr Report Abuse no
sluggopyle Champion Author North Carolina Posts:23,608 Points:1,075,890 Joined:Dec 2005	Message Posted: Apr 3, 2012 2:55:23 PM Ignore sluggopyle Report Abuse Well Jimmy, I drive a lot all over the eastern US and Canada, and I have yet to see an area where you could only get regular or diesel. Anywhere. I do see plenty of stations where you can't get diesel but that's not the question. The other point, yes the regular will burn, but at what price? How much is the mileage loss compared to the lower cost of the fuel? This is the question (I don't know the answer; haven't tried it yet). But if the loss in mpg translated to cost-per-mile is more than the gain in pump savings, then obviously it will be more expensive to run regular -- in the same way that running E10 costs more even if it's priced a dime lower than ethanol-free if the former creates a mileage loss greater than its own displacement. Bottom line: price per gallon ain't the whole story. [Edited by: sluggopyle at 4/3/2012 3:00:38 PM EST]
jimmy544 Champion Author Boston Posts:4,133 Points:655,805 Joined:Feb 2011	Message Posted: Apr 3, 2012 1:43:41 PM Ignore jimmy544 Report Abuse Even if your car manufacturer recommends that it be run on premium it will run on regular without any damage. It has to as per the government. The car may not be able to develop full power and performance may not be up to what it would be on the premium it will still run ok. It has to be that way as there are some places where you have a choice between diesel and regular gas and that is all you have to choose from. Run out of gas or run regular.
sluggopyle Champion Author North Carolina Posts:23,608 Points:1,075,890 Joined:Dec 2005	Message Posted: Apr 3, 2012 10:45:52 AM Ignore sluggopyle Report Abuse => Looks like most people don't understand the context here. <= I dunno about "most people" but it does seem to be a trend. I tried three times to explain this to Forresj; he just posted on my whiteboard "Up yours" followed verbatim by the same pig-ignorant post he's been trashing this thread with ("up yours"?? what is it, 1962 again?) Then the coward finds a way to lock his whiteboard so I can't respond. Funny he can figure out how to do that, yet he can't read the thread. I don't know why reading is so difficult for some, yet they think they're qualified to write. The OP is not rocket surgery; it says "to get to 91 (octane)". Nobody said squat about using MORE octane than you need; it assumes you already need the higher octane (why else would you be doing a mix like this -- duh). My knowledge from gas station managers confirms what BobSassafrass said-- they'll get a stock of regular and premium and mix the two to get mid-grade. One of my cars is designed for 93; on some future long trip I may try alternating grades to gauge the effects (presumably the fuel efficiency drops). But as BobSassafrass notes, the price differential may not justify it.
BobSassafrass Rookie Author Houston Posts:12 Points:5,595 Joined:Apr 2012	Message Posted: Apr 2, 2012 5:39:39 PM Ignore BobSassafrass Report Abuse Looks like most people don't understand the context here. I drive a 2006 Civic Si. The high compression motor calls for 91 octane or higher. Here in Texas I have only ever seen 93 octane. The OP probably has a similar situation, why pay 10 cents extra for 93 when your car will run on 91? So they want to purchase 5 gallons 89 and 5 gallons 93 to create 91 octane in the tank. We aren't trying to run lower grade the engine wants just get the slightly cheaper 91. I wasn't sure if mixing would actually be able to create 91 octane or just a mix of 89 and 93 but on the octane wiki page I found this: "Purchasing 91 octane fuel (where offered) simply means that more fuel of higher octane is blended with commensurately less fuel of lower octane, than when purchasing a lower grade. The detergents and other additives in the fuel are often, but not always, identical." So that said there should be no problem mixing to get 91. But like others have said this is penny pinching extreme. I get 10 gallons a week so this equates to a savings of $1 a week or $50 a year. While I most definitely make sure my phone, electricity, water, and food bills are as cheap as possible; saving a dollar a week is almost not worth the effort of having to put 2 different grades of gas in at one fill-up.
gasmask78 Champion Author Virginia Posts:2,288 Points:447,540 Joined:Sep 2011	Message Posted: Apr 2, 2012 12:30:44 AM Ignore gasmask78 Report Abuse Unless you drive a Mercedes or Rolls Royce...why get Premium?!!
Jescareno22 Veteran Author Toms River Posts:303 Points:58,070 Joined:Mar 2012	Message Posted: Apr 1, 2012 7:30:52 PM Ignore Jescareno22 Report Abuse no
sc331mustang Champion Author South Carolina Posts:2,154 Points:495,215 Joined:Nov 2011	Message Posted: Apr 1, 2012 6:13:03 PM Ignore sc331mustang Report Abuse I mostly buy mid-grade for my car that call for premium. As long as I am not flooring it and making the pistons rattle. For my motorcycle that also call for 93 octane I put 93 octane in it because of the high compression. 89 octane will make it spit and sputter. It is not worth damaging the motor when you can hear the difference.
forresj Champion Author Wilmington Posts:2,800 Points:546,180 Joined:May 2005	Message Posted: Apr 1, 2012 5:52:32 PM Ignore forresj Report Abuse it's a waste of money to mix fuel if your vehicle runs fine with just regular gas. you're paying extra to fund the CEO's mansion and hooker visits. you're also helping terrorists buy bombs to kill us.
sluggopyle Champion Author North Carolina Posts:23,608 Points:1,075,890 Joined:Dec 2005	Message Posted: Apr 1, 2012 4:15:12 PM Ignore sluggopyle Report Abuse So Forresj, you're going to keep repeating the same ignorant post even after it's been explained that you have the question backwards? Nice.
forresj Champion Author Wilmington Posts:2,800 Points:546,180 Joined:May 2005	Message Posted: Apr 1, 2012 11:53:51 AM Ignore forresj Report Abuse it's a waste of money to mix fuel if your vehicle runs fine with just regular gas. you're paying extra to fund the CEO's mansion and hooker visits. you're also helping terrorists buy bombs to kill us.
2011370Z Champion Author Phoenix Posts:5,983 Points:685,905 Joined:Apr 2011	Message Posted: Apr 1, 2012 10:26:05 AM Ignore 2011370Z Report Abuse My car calls for 91 but after talking with many mechanics I use 89. It works fine for my driving and saves me .10/gal.
ricebike Champion Author New Jersey Posts:10,043 Points:1,857,670 Joined:Oct 2005	Message Posted: Mar 31, 2012 6:38:51 PM Ignore ricebike Report Abuse ..
Jescareno22 Veteran Author Toms River Posts:303 Points:58,070 Joined:Mar 2012	Message Posted: Mar 31, 2012 4:36:55 PM Ignore Jescareno22 Report Abuse ,
sluggopyle Champion Author North Carolina Posts:23,608 Points:1,075,890 Joined:Dec 2005	Message Posted: Mar 27, 2012 10:24:04 AM Ignore sluggopyle Report Abuse Thanks Shock, perhaps it does. I am only the messenger, but the point was to counter the idea floated that "99%" of cars call for regular octane. Here's a comedy of errors post: => it's a waste of money to mix fuel if your vehicle runs fine with just regular gas. you're paying extra to fund the CEO's mansion and hooker visits. you're also helping terrorists buy bombs to kill us. <= You've assessed the point of the thread bass-ackwards. The idea is not to mix higher fuel than you need -- it's whether you can get away with lower than you need. And then the ridiculous end: terrorists and oil companies are in different businesses. Just because a terrorist comes from Saudi Arabia and so does oil doesn't mean they're the same people. Or do "they all look alike to you"?
gazprize Veteran Author Toronto Posts:483 Points:125,120 Joined:Jan 2012	Message Posted: Mar 27, 2012 10:14:41 AM Ignore gazprize Report Abuse no, do not mix
OceanArcher Champion Author Mississippi Posts:5,723 Points:1,331,300 Joined:May 2004	Message Posted: Mar 27, 2012 10:06:16 AM Ignore OceanArcher Report Abuse Fifty years ago, I did mix fuels - but not anymore
forresj Champion Author Wilmington Posts:2,800 Points:546,180 Joined:May 2005	Message Posted: Mar 27, 2012 9:43:27 AM Ignore forresj Report Abuse it's a waste of money to mix fuel if your vehicle runs fine with just regular gas. you're paying extra to fund the CEO's mansion and hooker visits. you're also helping terrorists buy bombs to kill us.
Shockjock1961 Champion Author Illinois Posts:20,148 Points:2,188,085 Joined:Apr 2006	Message Posted: Mar 27, 2012 9:28:36 AM Ignore Shockjock1961 Report Abuse I think that chart might have a few errors Sluggo. A vehicle I own is on that chart, just checked my owners manual, it states that my vehicle requires 87 Octane gasoline...
Dennis783 Champion Author Des Moines Posts:13,609 Points:2,706,810 Joined:Sep 2005	Message Posted: Mar 27, 2012 9:21:54 AM Ignore Dennis783 Report Abuse I just get regular in my car (premium in wife's car since that is what is recommended)
sluggopyle Champion Author North Carolina Posts:23,608 Points:1,075,890 Joined:Dec 2005	Message Posted: Mar 26, 2012 2:07:37 AM Ignore sluggopyle Report Abuse => 99% of the newer engine computers want, need low octane fuels. <= uh, NINETY-NINE percent?? No, not even close, and it's irresponsible to post that. Story >> The number of new vehicle models that need — or at least run better on — the priciest gasoline has steadily risen from 166 in the 2002 model year to 282 this year << list of models requiring premium (high octane) fuel (as of 2004) [Edited by: sluggopyle at 3/26/2012 2:15:11 AM EST]
PaylessKY Champion Author Kentucky Posts:8,740 Points:1,584,375 Joined:Oct 2008	Message Posted: Mar 26, 2012 12:45:23 AM Ignore PaylessKY Report Abuse If it works for you, no problem. [Edited by: PaylessKY at 3/26/2012 12:50:31 AM EST]
CaptDave2012 All-Star Author Arkansas Posts:695 Points:24,735 Joined:Feb 2012	Message Posted: Mar 25, 2012 11:16:32 PM Ignore CaptDave2012 Report Abuse 99% of the newer engine computers want, need low octane fuels. Read your manual and ask your mechanic, car dealer.
djdumlao Rookie Author Chicago Posts:99 Points:24,285 Joined:Apr 2008	Message Posted: Mar 25, 2012 9:42:14 PM Ignore djdumlao Report Abuse will mxing grade improve mpg?
plastic Champion Author Virginia Posts:46,842 Points:2,841,070 Joined:May 2004	Message Posted: Mar 25, 2012 9:28:59 PM Ignore plastic Report Abuse I've done that since the 80s with one car. Low octane would work fine if I drove normally and didn't push it. If I wanted to drive it the way that it was designed then I had to use higher octane. Through trial and error I found that I could get by with less than 93 and worked out a ratio that worked great. The timing gears were set pretty advanced on that cam. I mixed super with mid-grade. [Edited by: plastic at 3/25/2012 9:33:34 PM EST]
Shockjock1961 Champion Author Illinois Posts:20,148 Points:2,188,085 Joined:Apr 2006	Message Posted: Mar 25, 2012 8:24:52 PM Ignore Shockjock1961 Report Abuse I make it a point not to buy a vehicle that needs to run on premium. What a waste...
Jmac2008 Champion Author Missouri Posts:2,289 Points:884,065 Joined:Dec 2008	Message Posted: Mar 25, 2012 7:40:24 PM Ignore Jmac2008 Report Abuse I just run 87
Gas_Buddy Champion Author Maryland Posts:25,986 Points:3,036,015 Joined:Aug 2004	Message Posted: Mar 25, 2012 6:39:37 PM Ignore Gas_Buddy Report Abuse sluggopyle: "No no GB, I see what he means. He's supposed to be running premium, but wants to cheat in some mid-grade now and then so as to save money by 'diluting' his fuel without sacrificing too much octane." I know what I think he might have meant, but I try to give the person credit by assuming they know what they're asking. In this case the member asked if anyone mixes premium and mid-grade... Is it too much to expect the question asked to be what they want to know, or is it too much to expect what they say to be what they mean?
tdioiler All-Star Author Detroit Posts:895 Points:421,625 Joined:Jul 2011	Message Posted: Mar 25, 2012 4:06:21 PM Ignore tdioiler Report Abuse Any car that says they 'have' to use premium isn't worth it since: A) If I'm cruising around town without racing, who cares B) My MPG won't be what I was told at the dealer but I'm saving money anyway?? C) A bike is way cheaper and more fun to ride !!
chemist74 Champion Author Cleveland Posts:13,510 Points:2,395,980 Joined:Apr 2005	Message Posted: Mar 25, 2012 1:35:51 PM Ignore chemist74 Report Abuse No - I have always been smart enough to only buy vehicles that run onregular gasoline.
kxy4fw Champion Author Denver Posts:1,226 Points:275,355 Joined:Nov 2011	Message Posted: Mar 25, 2012 12:25:52 PM Ignore kxy4fw Report Abuse Mid-grade only.
PatAZ Champion Author Tucson Posts:9,253 Points:122,460 Joined:May 2008	Message Posted: Mar 25, 2012 11:46:34 AM Ignore PatAZ Report Abuse When I get gas I buy premium as the manual says.
sluggopyle Champion Author North Carolina Posts:23,608 Points:1,075,890 Joined:Dec 2005	Message Posted: Mar 25, 2012 10:32:00 AM Ignore sluggopyle Report Abuse => I will not buy a vehicle that is supposed to run on premium. <= You can't always git what you want. Some cars are just not made that way, even if we want them to be. << this one f'rinstance. Is it worth it to have the car? Oooooh yeah! Another thing to keep in mind: with the different grades being priced a dime apart, the more the general price of fuel goes up, the less significant that difference is- consequently premium becomes less and less relatively expensive. When gas is one dollar a gallon, a dime difference is 10% -- when it's $4 a gallon, that dime difference is 2.5%. And it means 2.5% of a dollar that's worth less too. In the big picture with neighboring gas stations pricing themselves even less than a dime apart, the savings from one station to the next become less and less significant. In other words, ironically the more fuel prices go up in general, the less relevant this website's purpose is. [Edited by: sluggopyle at 3/25/2012 10:37:46 AM EST]
ricebike Champion Author New Jersey Posts:10,043 Points:1,857,670 Joined:Oct 2005	Message Posted: Mar 25, 2012 10:13:51 AM Ignore ricebike Report Abuse if you just have a high compression eninge and not turbo, you MAY get away with going lower than what's recommended just have to accept that your knock sensor is going to work overtime and then you'll lose some HP and mpg
jes Champion Author Pennsylvania Posts:16,180 Points:3,355,400 Joined:Jun 2003	Message Posted: Mar 25, 2012 7:41:10 AM Ignore jes Report Abuse No. My vehicles are made to run on regular and they do so just fine. I will not buy a vehicle that is supposed to run on premium.
GBHUGVA Champion Author Virginia Beach Posts:4,697 Points:789,160 Joined:Mar 2009	Message Posted: Mar 25, 2012 7:23:53 AM Ignore GBHUGVA Report Abuse only when driving in the mountains other wise just use reg.
bonbNJ All-Star Author New Jersey Posts:979 Points:326,940 Joined:Apr 2011	Message Posted: Mar 25, 2012 5:50:18 AM Ignore bonbNJ Report Abuse desperation
sluggopyle Champion Author North Carolina Posts:23,608 Points:1,075,890 Joined:Dec 2005	Message Posted: Mar 25, 2012 12:33:15 AM Ignore sluggopyle Report Abuse No no GB, I see what he means. He's supposed to be running premium, but wants to cheat in some mid-grade now and then so as to save money by 'diluting' his fuel without sacrificing too much octane. << this car is supposed to be sipping premium, and I've thought about that, but haven't tried it (yet).
Gas_Buddy Champion Author Maryland Posts:25,986 Points:3,036,015 Joined:Aug 2004	Message Posted: Mar 24, 2012 10:38:58 PM Ignore Gas_Buddy Report Abuse That makes absolutely no sense. Why would you go through the trouble of mixing premium and mid-grade to get the mid-grade octane? And then essentially write "mix premium and regular, rather than mix premium and mid-grade, because of the pripce difference". That makes no sense. Of course I have no idea why you'd even wonder about whether people "just get Premium and the occasional mid-grade" when gas prices, at least form the perspective of price posting, doesn't seem to be of any concern. Not being cynical, but with about one gas price every other month for the past ten years, are you really interested in if people mix grades of gas to get a different grade? Just asking; that's all. Just asking.