I taught someone how to save on 89 octane

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I used to work with a guy that drove a little Toyota truck with the 22R four cylinder engine . He would burn premium gas in it to " make my truck last longer " . Figure that one out . Also , if he was on the highway at cruising speed he would turn the AC off and roll down the window . Same reason . We just smiled and waved ...
 
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Just don't do the practice that many did here in the midwest in the mid 70's during the shortages. People who owned cars that needed premium leaded fuels bought regular leaded fuel and then dropped moth balls (made from naptha) in their tanks to try to raise octane ratings. This practice gummed up the mechanical diaphragm fuel pumps something fierce. Of course these were the same folk who put magnets on their fuel lines to get better gas mileage.

JC Gyp Me, I mean Whitney made thousands off this type of merchandise.

 
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AutoMechanic

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I’m one that insists on using 89 too lol. Especially in my old stuff it just seems to do better. My truck shakes like mad when you use 87 for some reason though it specs 87 but 89 or 93 here seems to be ok. I’m guessing because generally the higher the octane the less the ethanol in general, not always the case. Only thing I would change from your mix is it would have to be half 87 and half 93 so that way it’s exactly equivalent to what you get at the pump.
 
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Use 89 in the wifes 08 Malibu LTZ 3.6, states in the manual 87 is good but 89 will give the best performance. :D
 
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Use 89 in the wifes 08 Malibu LTZ 3.6, states in the manual 87 is good but 89 will give the best performance. :D
I can confirm. Drove a 09 Malibu 3.6 and the engine and shifting performance was worlds better at all temps with at least 89 octane. The mileage increased enough that it would almost entirely offset the increase in price for 89 at least in my area.

For anyone else that thinks a vehicle recommending 87 cant be improved with performance and mileage by running more octane..... It depends on the car and about a half a dozen other environmental factors.

Same issue with my Regal GS. The manual recommends 91 octane minimum and power increases very noticeably with 93 in the tank. Logging the MAF meter with Torque Pro you'll see a max of about 205-212 grams per second and WOT on 91 octane fuel. With 93 in the tank you'll see more timing and boost and readings and 217-221 grams per second at WOT from the MAF. That is a difference of 10-15 hp.
 
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I have the QT PumpStart card so I throw my pocket change in filling with non ethanol then go in an pay and use the facilities then head out and pay for the E10. My guess is my tank gets roughly a e9 with a 88 octane rating in my tank.
 
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I worked for a major oil company. Most gas stations have two underground gasoline storage tanks. One for regular and one for premium.

89 octane gasoline was blended at the dispenser using 65% 87 octane regular and 35% 93 octane premium.

The ones that had old style seperate pumps with no in pump blending and individual tank for 89 the tanker driver dropped 1 gallon of 93 to 2 gallons of of 87 and they charged half way in between, making additional profit.
 
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Ford recommends 91 octane for the Maverick's Hybrid. Recently put a tank of 89 E10 followed by the current tank of 91 E0. Have used a bit over a quarter tank and I am at 18X miles. This is with a higher % of highway driving than normal.
 
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It seems like having the attendant drip gas down his fender twice per fillup instead of just once would offset that small cost savings.
 
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I can confirm. Drove a 09 Malibu 3.6 and the engine and shifting performance was worlds better at all temps with at least 89 octane. The mileage increased enough that it would almost entirely offset the increase in price for 89 at least in my area.

For anyone else that thinks a vehicle recommending 87 cant be improved with performance and mileage by running more octane..... It depends on the car and about a half a dozen other environmental factors.

Same issue with my Regal GS. The manual recommends 91 octane minimum and power increases very noticeably with 93 in the tank. Logging the MAF meter with Torque Pro you'll see a max of about 205-212 grams per second and WOT on 91 octane fuel. With 93 in the tank you'll see more timing and boost and readings and 217-221 grams per second at WOT from the MAF. That is a difference of 10-15 hp.
My Accent runs like crap on 87, pings like mad at highway speeds and acceleration is noticeably worse. I think I actually get better gas mileage on 87 mostly because I can't drive around as fast.
 
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I'm not sure the dilution is linear as in 1 gallon of 87 plus one gallon of 93 equals 2 gallons of 90. You need a chemical engineer to explain it and I don't remember the details now, but it's something like the lower octane will reduce the higher octane rate greater than the ratio of the mix. So my example may give 89 octane and yours, 88. Not that your guy would ever notice.
89 is literally a 50/50 mix of 87/91. He's probably close with his mix of 93/87.
 
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