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Old 05-14-2012, 08:15 PM   #1
Mrknowitall
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Thumbs down Best fuel!?/////Whered all the 92octane go?!

California valley user here, i cant find 92octane anymore! What the heck!?

What about other states!? What ratings can you get? Ethanol %?

anyone eaisly get 85octane?

And finally what do u run and why?

Im running a compresion ration of aprox 9:5:1

She pings with 87, 89 is just 87 and 91 blended so i stay away from that, 91 runs great in winter, ritch in summer.


Check this out, do a test. Buy 20 bucks woth of 87 then 91/92. Do u get more with the higher rated?
I have a newer sending unit and guage on a single 12g tank so needle accuracy is pretty good, and with 92 the needle is higher despite the price increase.

I also get better mpg with higher octane despite timing or comp ratio.

Tested in my 2003 hundai sonata v6 with cold air intake, averaged 2 mpg better with cold air, 2 mph better with octane...

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Old 05-14-2012, 09:36 PM   #2
ymerej71
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Re: Best fuel!?/////Whered all the 92octane go?!

Here in small town, Gainesville TX I can still by ethanol free 85 octane fuel at the local farm co-op. It runs clean in my 454, and I actually get a little better mileage with it... As far as mileage is concerned with a big block. Haha..
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Old 05-14-2012, 09:42 PM   #3
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Re: Best fuel!?/////Whered all the 92octane go?!

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Originally Posted by ymerej71 View Post
Here in small town, Gainesville TX I can still by ethanol free 85 octane fuel at the local farm co-op. It runs clean in my 454, and I actually get a little better mileage with it... As far as mileage is concerned with a big block. Haha..
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Wow! Really!? Nearest 85 is 60 miles from me, that big block dosent ping on 85!? Thats insane. Whats your timing?
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Old 05-14-2012, 09:55 PM   #4
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Re: Best fuel!?/////Whered all the 92octane go?!

Quote:
Originally Posted by ymerej71 View Post
Here in small town, Gainesville TX I can still by ethanol free 85 octane fuel at the local farm co-op. It runs clean in my 454, and I actually get a little better mileage with it... As far as mileage is concerned with a big block. Haha..
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Ethanol is less efficient in anyway compared to ethanol free gas. Plus it makes grocreys more expensive
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Old 05-14-2012, 09:59 PM   #5
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Re: Best fuel!?/////Whered all the 92octane go?!

I run 87 in my LS4 Impala. No knocking or pinging.
Higher octane fuels burn slower. It's entirely possible to fill the pistons and head chambers with enough carbon to make the engine ping on fuel it would've happily burned before you started running the "good stuff".
Run the lowest octane that doesn't ping.

Mileage based on "I think the gauge shows full longer" is anecdotal evidence at best. Worst case it's just plain wrong. This is one of those rose colored glasses moments.
I did several test runs with more expensive B20 Biodiesel in my truck. My rose colored glasses told me I was getting better mileage... NOPE. at best I gained .3 mpg and at worst I lost 2mpg... You need to know whether you're really getting better mileage using cold hard numbers. Keep your "feelings" out of the equation.

The only way to calculate MPG is based on full tanks with no partial fillups in between.
MPG=((Miles at this fill)-(Miles at last fill))/(Gallons to fill the tank)
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Old 05-14-2012, 10:09 PM   #6
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Re: Best fuel!?/////Whered all the 92octane go?!

Quote:
Originally Posted by GM-power View Post
Plus it makes grocreys more expensive
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Ahahahahahahahahahahahah!!!!! Feeding my town man!

Quote:
Originally Posted by hatzie View Post
I run 87 in my LS4 Impala. No knocking or pinging.
Higher octane fuels burn slower. It's entirely possible to fill the pistons and head chambers with enough carbon to make the engine ping on fuel it would've happily burned before you started running the "good stuff".
Run the lowest octane that doesn't ping.

Mileage based on "I think the gauge shows full longer" is anecdotal evidence at best. Worst case it's just plain wrong. This is one of those rose colored glasses moments.
I did several test runs with more expensive B20 Biodiesel in my truck. My rose colored glasses told me I was getting better mileage... NOPE. at best I gained .3 mpg and at worst I lost 2mpg... You need to know whether you're really getting better mileage using cold hard numbers. Keep your "feelings" out of the equation.

The only way to calculate MPG is based on full tanks with no partial fillups in between.
MPG=((Miles at this fill)-(Miles at last fill))/(Gallons to fill the tank)
Good points, any one else? No ones cussing yet
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Old 05-14-2012, 10:45 PM   #7
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Re: Best fuel!?/////Whered all the 92octane go?!

i run 87 in everything new old etc. no problems
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Old 05-14-2012, 10:55 PM   #8
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Re: Best fuel!?/////Whered all the 92octane go?!

I use 87 mostly. Used 91 today as the truck didn't like some 87 I got from a place I don't usually go to. I'm sure there are some other places, but I know 85 is available at the gas station on the way to Lake Mead here.
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Old 05-14-2012, 11:22 PM   #9
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Re: Best fuel!?/////Whered all the 92octane go?!

We have 10% ethanol in our fuel in SLC.
Stock '87 V20 I used to be able to run 85 octane. Now I run 87.
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Old 05-14-2012, 11:35 PM   #10
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Re: Best fuel!?/////Whered all the 92octane go?!

I run nothing but 91 octane here (I have aggressive tunes in everything), it's the highest junk available here. You may find mileage varies a bit due to the ethanol content not being consistent from station to station.

I use a cheap ethanol test kit (they are everywhere on the internet) and test the gas once in a while. I've found as high as 17% at a pump that claims 10% max Needless to say that tank of gas may produce subpar fuel mileage numbers.

With that said, Even my computer controlled LS engines here have custom tunes that are about as aggressive as I can get on 91 octane. I do pretty well on fuel mileage considering...

2000 SS camaro 6 speed gets 23 in town and 30 highway.

72 4x4 blazer 6.0/4L60E swap and 3.73's gets 18 in town and 22 highway.

79 1 ton pickup now with a 502 crate motor and 400 turbo/3.73 gear 12 mpg in town and 14 mpg highway.

Those I drive the most. A bunch of classic muscle cars that I drive infrequently aren't too bad, anywhere from 10 mpg (650hp 454) to 16 mpg from a stock 70 400 formula, and a few in between.

You can find alot of fuel mileage tuning with a wideband Gas isn't what it used to be. I average about a 1-2 mpg drop compared to the ethanol free gas I used to run.

A tip that I do, and I do this in all the cars whether carbed or fuel injection, is to add 2 cycle engine oil with a TC-W3 rating with every fillup. It acts as a cleaner and a lubricator, and has actually picked up an average of 1 or 2 mpg in each car if used consistently on every fillup, quicker starts, smoother running, lubricates the valves (remember lead in the gas is gone now), cleans the tops of the pistons, cleans sparkplugs, cleans fuel system, injectors, lubes the electric fuel pump (If you have one), and one odd benefit that I've noticed is that it also seems to stabalize the ethanol content from pump to pump, so using this should also cut down on any corrosion issues and you also get a more consistent running engine from tank to tank.

I only add 1 oz per gallon of gas and keep the 5 quart jug and a measuring jar with what ever car I'm driving. $11 at your local walmart and it will treat about 600 gallons of gas. Alot cheaper than any other fuel cleaner and it works better. I even run it in my lawn equipment
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Old 05-15-2012, 12:24 AM   #11
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Re: Best fuel!?/////Whered all the 92octane go?!

i havent thought about using the 2cycle oil in my newest truck 2009 f150 i may have to try it. i do use the 2cycle oil in every carbed motor i own. i buy 87 thats ethenal free at 3 stations around jackson ms all 3 are mom and pop places but have never had issues with fuel. neither of my old carbed motors have an issue with 87. my ford runs well no matter what fuel you drop in it. i do run e85 and mostly 87 with 10% e from the kangaroo station.( high traffic lots of gas sold outta there) or i go to the loves truck stop.
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Old 05-15-2012, 09:47 AM   #12
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Re: Best fuel!?/////Whered all the 92octane go?!

I've heard of running 2stroke oil in Diesels to make up for the lost lubricity in the low sulfur fuel... I run 1 qt of Dexron III every 3/4 tank in the trucks. No way to tell whether the Dexron is doing any good... There's no obvious change in mileage with vs without. The pumps are still working well... but they might keep working well without it too. It's not coking up the pre-chambers like straight waste veggie oil. SO. The best thing I can say about it is "It's not doing any damage.".


No problems with carbon buildup in the exhaust ports from the 2 stroke oil? I just replaced the blocked up spark screen and scraped out the 1/2 blocked exhaust ports on my Stihl trimmer. Do it every 2 years or so. Admittedly 50:1 on Stihl oil is a much higher mix ratio than what you're describing.
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Old 05-15-2012, 11:16 AM   #13
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Re: Best fuel!?/////Whered all the 92octane go?!

I run 87 on a ZZ4 with 10:1 compression. Runs great, but it does have max timing on it. I turn it off in gear when it's hot outside.
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Old 05-15-2012, 11:25 AM   #14
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Re: Best fuel!?/////Whered all the 92octane go?!

Quote:
Originally Posted by hatzie View Post
I've heard of running 2stroke oil in Diesels to make up for the lost lubricity in the low sulfur fuel... I run 1 qt of Dexron III every 3/4 tank in the trucks. No way to tell whether the Dexron is doing any good... There's no obvious change in mileage with vs without. The pumps are still working well... but they might keep working well without it too. It's not coking up the pre-chambers like straight waste veggie oil. SO. The best thing I can say about it is "It's not doing any damage.".


No problems with carbon buildup in the exhaust ports from the 2 stroke oil? I just replaced the blocked up spark screen and scraped out the 1/2 blocked exhaust ports on my Stihl trimmer. Do it every 2 years or so. Admittedly 50:1 on Stihl oil is a much higher mix ratio than what you're describing.
No carbon buildup issues with the mix I use, but as you mentioned, 2 stroke engines use a very high mix ratio. I only use 1oz per 5 gallons of gas.
By the way,,,that's a typo in my original post and I can't go back and correct it (seems the edit option disappears after a while)

It's 1oz per 5 gallons of gas.
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Old 05-15-2012, 05:48 PM   #15
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Re: Best fuel!?/////Whered all the 92octane go?!

Hummm the 2 smoke idea is a goodone. Your claiming 12 mpg in a carbed bb?! Thats insane.

I average 11 when babying it in my 350.
Shes got ele fans mild cam gear drive and 60s 327 vette heads.

Any reccomendations? And yes in using the cold air stock tube.
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Old 05-15-2012, 09:02 PM   #16
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Re: Best fuel!?/////Whered all the 92octane go?!

No 85 around here that I know of. I run 91 in mine. Today's price $3.43. 1 station selling straight gas. 8:1 compression with 10 lb of boost. Pushing the envelope for pump gas so this helps tame the dreaded detonation issue, along with the ecu varying the timing thru the power band. LOL, can't really do the test as I have a condition in my right foot known as lead foot syndrome. Just wouldn't be any way to accurately measure the results. City: anybody's guess. Highway: 10 mpg
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Old 05-15-2012, 10:43 PM   #17
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Re: Best fuel!?/////Whered all the 92octane go?!

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Hummm the 2 smoke idea is a goodone. Your claiming 12 mpg in a carbed bb?! Thats insane.
Yes, not sure which one you speak of but I assume it's my pickup,,,,a 79 1 ton, I'm running a GM crate HT502 (orig 454 spun a bearing) with the original 400 turbo behind it, and 3.73 gears.

I get 12 mpg around town driving it easy,,,and I get 14 mpg highway if I keep speeds reasonable,,,,65ish. If I push it on the highway at say,,,70-75ish then it drops to about 12 mpg highway.

I tow a 28 foot trailer loaded (about 10,000 lbs.) and I get right at 10 mpg highway cruising a steady 65 mph.

Alot of it is tuneup and maintanance, I keep a sharp tune on it using a wideband to dial it in (on every car). My little 2 cycle oil trick helps a tad, but I mainly do that to keep the top half of the engine lubed and clean (in all the cars).
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Old 05-15-2012, 11:47 PM   #18
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Re: Best fuel!?/////Whered all the 92octane go?!

I didn't know there was 85 available. We have 87, 89, and 93 here.
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Old 05-16-2012, 02:39 AM   #19
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Re: Best fuel!?/////Whered all the 92octane go?!

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I didn't know there was 85 available. We have 87, 89, and 93 here.
Yes. Chevy pushed for it as alt fuel for theyre eco line blazers. Its made from corn, to eliminate foreign fuel dependencies.
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Old 05-16-2012, 03:09 AM   #20
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Re: Best fuel!?/////Whered all the 92octane go?!

Also, to anyone who cares, and/or doesn't know...there are two types of 85. There's E85, an ehtanol/gas blend, which should NOT be run in our trucks, and there is in some places an 85 octane gasoline. Just like 87, but two less octane. This second kind is what I posted about being near the lake here. There are lots of E85 stations all over town here.
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Old 05-16-2012, 11:58 AM   #21
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Re: Best fuel!?/////Whered all the 92octane go?!

I've heard of E85, just never seen it. The 85 octane is what I've never heard of.
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Old 05-16-2012, 04:49 PM   #22
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Re: Best fuel!?/////Whered all the 92octane go?!

And if you haven't noticed,,,the price of E85 is slowly catching up to the cost of regular gas.

They lost their government incentives to produce it, so without the extra government funding the price of E85 has been climbing. Last I saw it was only .75 cents different from regular gas. Since you'll burn it at a faster rate of about 30%,,,it's not looking like a good alternative anymore.

We need to just start drilling here and quit depending on foreign oil. Not only would gas prices drop (that alone would boost the economy), but it would create thousands of jobs, something else we need desperately.
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Old 05-16-2012, 04:54 PM   #23
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Re: Best fuel!?/////Whered all the 92octane go?!

That would be to easy.
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Old 05-16-2012, 05:00 PM   #24
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Re: Best fuel!?/////Whered all the 92octane go?!

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That would be to easy.
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Old 05-16-2012, 10:08 PM   #25
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Re: Best fuel!?/////Whered all the 92octane go?!

they claim we have tons of natural gas here lets burn it they use it alot elsewhere
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