The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 05-14-2012, 08:15 PM   #1
Mrknowitall
Registered User
 
Join Date: May 2012
Location: Visalia CA
Posts: 118
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...

Ding ding! FIGHT!
Posted via Mobile Device

Last edited by Mrknowitall; 05-14-2012 at 08:19 PM. Reason: Sp
Mrknowitall is offline   Reply With Quote
Old 05-14-2012, 09:36 PM   #2
ymerej71
Registered User
 
ymerej71's Avatar
 
Join Date: Jan 2011
Location: Gainesville, TX
Posts: 144
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..
Posted via Mobile Device
ymerej71 is offline   Reply With Quote
Old 05-14-2012, 09:42 PM   #3
Mrknowitall
Registered User
 
Join Date: May 2012
Location: Visalia CA
Posts: 118
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..
Posted via Mobile Device
Wow! Really!? Nearest 85 is 60 miles from me, that big block dosent ping on 85!? Thats insane. Whats your timing?
Posted via Mobile Device
Mrknowitall is offline   Reply With Quote
Old 05-14-2012, 09:55 PM   #4
GM-power
Registered User
 
GM-power's Avatar
 
Join Date: Mar 2012
Location: Little Rock, Arkansas
Posts: 770
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..
Posted via Mobile Device
Ethanol is less efficient in anyway compared to ethanol free gas. Plus it makes grocreys more expensive
Posted via Mobile Device
GM-power is offline   Reply With Quote
Old 05-14-2012, 09:59 PM   #5
hatzie
Moderator
 
hatzie's Avatar
 
Join Date: Oct 2008
Location: Wentworth, NH
Posts: 4,977
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)
__________________
1959 M35A2 LDT465-1D SOLD
1967 Dodge W200 B383, NP420/NP201 SOLD
1969 Dodge Polara 500 B383, A833 SOLD
1972 Ford F250 FE390, NP435/NP205 SOLD
1976 Chevy K20, 6.5L, NV4500/NP208 SOLD
1986 M1008 CUCV SOLD
2000 GMC C2500, TD6.5L, NV4500
2005 Chevy Silverado LS 2500HD 6.0L 4L80E/NP263
2009 Impala SS LS4 V8


RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials...Please include at least the year and model in your threads. It'll be easier to answer your questions.
And please let us know if and how your repairs were successful.
hatzie is offline   Reply With Quote
Old 05-14-2012, 10:09 PM   #6
Mrknowitall
Registered User
 
Join Date: May 2012
Location: Visalia CA
Posts: 118
Re: Best fuel!?/////Whered all the 92octane go?!

Quote:
Originally Posted by GM-power View Post
Plus it makes grocreys more expensive
Posted via Mobile Device
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
Posted via Mobile Device
Mrknowitall is offline   Reply With Quote
Old 05-14-2012, 10:45 PM   #7
Hubscrub
Cruzin
 
Hubscrub's Avatar
 
Join Date: Dec 2009
Location: on the road
Posts: 2,835
Re: Best fuel!?/////Whered all the 92octane go?!

i run 87 in everything new old etc. no problems
__________________
Lime Wife's 67https://www.google.com/url?sa=t&rct=...wZEMODaS2d94u8

Back to the Fifties 59 https://www.google.com/url?sa=t&rct=...NAeStpydfrcj_U

Proverbs 3:5,6

"Thanks to the Interstate Highway System, it is now possible to travel across the country from coast to coast without seeing anything."Charles Kuralt

In memory of our first baby daughter, daddy and mommy love you.
Danica Grace 6/26/14
Hubscrub is offline   Reply With Quote
Old 05-14-2012, 10:55 PM   #8
TheApocalyptican
Registered User
 
TheApocalyptican's Avatar
 
Join Date: Jun 2010
Location: Las Vegas, Nv
Posts: 312
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.
__________________
1995 Suburban K2500 454.....off road & towing
1999 Astro, work van
2006 Silverado 2wd 5.3 w/4.5" lift and 33s
TheApocalyptican is offline   Reply With Quote
Old 05-14-2012, 11:22 PM   #9
Zane M
Registered User
 
Join Date: Dec 2006
Location: SLC, UT
Posts: 706
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.
Zane M is offline   Reply With Quote
Old 05-14-2012, 11:35 PM   #10
Firebirdjones
Registered User
 
Join Date: Oct 2009
Location: Prescott, Arizona
Posts: 2,396
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
Firebirdjones is offline   Reply With Quote
Old 05-15-2012, 12:24 AM   #11
butch86
Registered User
 
butch86's Avatar
 
Join Date: Mar 2012
Location: harrisville, ms
Posts: 377
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.
__________________
most people sleep peacfully at night because, rough men stand ready to do violenceon there behalf.
butch86 is offline   Reply With Quote
Old 05-15-2012, 09:47 AM   #12
hatzie
Moderator
 
hatzie's Avatar
 
Join Date: Oct 2008
Location: Wentworth, NH
Posts: 4,977
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.
__________________
1959 M35A2 LDT465-1D SOLD
1967 Dodge W200 B383, NP420/NP201 SOLD
1969 Dodge Polara 500 B383, A833 SOLD
1972 Ford F250 FE390, NP435/NP205 SOLD
1976 Chevy K20, 6.5L, NV4500/NP208 SOLD
1986 M1008 CUCV SOLD
2000 GMC C2500, TD6.5L, NV4500
2005 Chevy Silverado LS 2500HD 6.0L 4L80E/NP263
2009 Impala SS LS4 V8


RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials...Please include at least the year and model in your threads. It'll be easier to answer your questions.
And please let us know if and how your repairs were successful.
hatzie is offline   Reply With Quote
Old 05-15-2012, 11:16 AM   #13
gchemist
BAD BOW-Silverado XST
 
gchemist's Avatar
 
Join Date: May 2000
Location: Senior Member from Austin, TX
Posts: 6,431
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.
__________________
Gerardo a.k.a. Mad Chemist
Silverado XST videos
gchemist is offline   Reply With Quote
Old 05-15-2012, 11:25 AM   #14
Firebirdjones
Registered User
 
Join Date: Oct 2009
Location: Prescott, Arizona
Posts: 2,396
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.
Firebirdjones is offline   Reply With Quote
Old 05-15-2012, 05:48 PM   #15
Mrknowitall
Registered User
 
Join Date: May 2012
Location: Visalia CA
Posts: 118
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.
Posted via Mobile Device
Mrknowitall is offline   Reply With Quote
Old 05-15-2012, 09:02 PM   #16
CoggedBelt75
Registered User
 
CoggedBelt75's Avatar
 
Join Date: Nov 2008
Location: Altus, Oklahoma
Posts: 679
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
__________________
Joe
__________________________________________
1975 C10

"Questions are a sign of intelligence indicating a desire to eliminate ignorance"
CoggedBelt75 is offline   Reply With Quote
Old 05-15-2012, 10:43 PM   #17
Firebirdjones
Registered User
 
Join Date: Oct 2009
Location: Prescott, Arizona
Posts: 2,396
Re: Best fuel!?/////Whered all the 92octane go?!

Quote:
Originally Posted by Mrknowitall View Post
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).
Firebirdjones is offline   Reply With Quote
Old 05-15-2012, 11:47 PM   #18
jablack
Classic Chevy Recycler
 
jablack's Avatar
 
Join Date: Dec 2007
Location: Alabama
Posts: 422
Re: Best fuel!?/////Whered all the 92octane go?!

I didn't know there was 85 available. We have 87, 89, and 93 here.
__________________


2004 Chevrolet Trailblazer EXT
1970 Chevrolet C50
1979 Chevrolet C30

Need another 67 or 68 soon...
jablack is offline   Reply With Quote
Old 05-16-2012, 02:39 AM   #19
Mrknowitall
Registered User
 
Join Date: May 2012
Location: Visalia CA
Posts: 118
Re: Best fuel!?/////Whered all the 92octane go?!

Quote:
Originally Posted by jablack View Post
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.
Posted via Mobile Device
Mrknowitall is offline   Reply With Quote
Old 05-16-2012, 03:09 AM   #20
TheApocalyptican
Registered User
 
TheApocalyptican's Avatar
 
Join Date: Jun 2010
Location: Las Vegas, Nv
Posts: 312
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.
__________________
1995 Suburban K2500 454.....off road & towing
1999 Astro, work van
2006 Silverado 2wd 5.3 w/4.5" lift and 33s
TheApocalyptican is offline   Reply With Quote
Old 05-16-2012, 11:58 AM   #21
jablack
Classic Chevy Recycler
 
jablack's Avatar
 
Join Date: Dec 2007
Location: Alabama
Posts: 422
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.
__________________


2004 Chevrolet Trailblazer EXT
1970 Chevrolet C50
1979 Chevrolet C30

Need another 67 or 68 soon...
jablack is offline   Reply With Quote
Old 05-16-2012, 04:49 PM   #22
Firebirdjones
Registered User
 
Join Date: Oct 2009
Location: Prescott, Arizona
Posts: 2,396
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.
Firebirdjones is offline   Reply With Quote
Old 05-16-2012, 04:54 PM   #23
jablack
Classic Chevy Recycler
 
jablack's Avatar
 
Join Date: Dec 2007
Location: Alabama
Posts: 422
Re: Best fuel!?/////Whered all the 92octane go?!

That would be to easy.
__________________


2004 Chevrolet Trailblazer EXT
1970 Chevrolet C50
1979 Chevrolet C30

Need another 67 or 68 soon...
jablack is offline   Reply With Quote
Old 05-16-2012, 05:00 PM   #24
Firebirdjones
Registered User
 
Join Date: Oct 2009
Location: Prescott, Arizona
Posts: 2,396
Re: Best fuel!?/////Whered all the 92octane go?!

Quote:
Originally Posted by jablack View Post
That would be to easy.
Firebirdjones is offline   Reply With Quote
Old 05-16-2012, 10:08 PM   #25
Hubscrub
Cruzin
 
Hubscrub's Avatar
 
Join Date: Dec 2009
Location: on the road
Posts: 2,835
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
__________________
Lime Wife's 67https://www.google.com/url?sa=t&rct=...wZEMODaS2d94u8

Back to the Fifties 59 https://www.google.com/url?sa=t&rct=...NAeStpydfrcj_U

Proverbs 3:5,6

"Thanks to the Interstate Highway System, it is now possible to travel across the country from coast to coast without seeing anything."Charles Kuralt

In memory of our first baby daughter, daddy and mommy love you.
Danica Grace 6/26/14
Hubscrub is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 02:20 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com