High gas prices..how about regular?

[gitchies]

yeah might have to give it a shot with a few tanks of 87....i'm curious...i'm at about $5 a gallon here in ontario....

[diyanich]

Originally Posted by gitchies

yeah might have to give it a shot with a few tanks of 87....i'm curious...i'm at about $5 a gallon here in ontario....

I used few tanks of 87 from Esso and I could feel a power loss and engine was sounding differently,so I went and tried the premium and wouldn't say it was better than 89 in anyway,I run 89 for 2 years already..no complaints on performance..only the price
Once I read an article about gas and what it was pointing to : use lower octane in winter,use higher octane in summer.
I'll stick with 89 I think it's the golden middle point.
V8 has plenty of power and I am averaging 17-15mpg mostly city driving.

[gitchies]

might have to give a try...i've always wondered if it was more a myth about premium gas and me just falling for the marketing!!! i only use shell gas....i've tried esso in my audi....and it didn't seem to work very well....so i went back to using only shell since i was 16.

[Buzzcut]

I'm going to throw a hand grenade into this conversation...

I started mixing E85 into my gas. E85 is 105 octane, and costs $3.00 a gallon when 87 is $3.50 and 93 is $3.70.

I started with 4 gallons of E85, to get about 89 octane. Next tank was 5 gallons, getting me to about 90 octane. I'm going to build up to 7 gallons, which will be a little over 91 octane.

Right now, the tank is about 22% ethanol. At 7 gallons, it will be about 29%.

It is hard to say if there is a hit to mileage. We've had a very hard winter here in Chicago, very cold and snowy, and my mileage has been just awful. Unfortunately, I started mixing when the weather warmed up a bit, and it looks like my mileage improved. I'm sure that it has nothing to do with the ethanol, it's the weather.

I've mixed E85 with gas in my previous car (see my blog The Drunken Swede), so I have some experience with this. We shall see about reliability and durability using increased amounts of ethanol (it was not an issue on an '07 Saab for 15,000 miles of driving with 30% ethanol). I'm prepared to replace whatever needs to be replaced if it breaks.

[CT_X5_Joe]

Originally Posted by albertax5

i tried 2 tanks in my 06 4.4.seemed to run the same but my in town fuel mileage went from 19-20mpg to 14-15 mpg.so the extra cost of the 91 and the drop in mpg with regular might balance itself out...we are paying about 5$ a gallon here in alberta..

How do you get 19-20mpg around town? I get about 15 in my 2006 4.4i that just hit 20k miles yesterday.

[HPIA4v2]

Originally Posted by gitchies

might have to give a try...i've always wondered if it was more a myth about premium gas and me just falling for the marketing!!! i only use shell gas....i've tried esso in my audi....and it didn't seem to work very well....so i went back to using only shell since i was 16.

If the engine can take advantage higher octane it'll produce more power it's not myth.
I've been participating in e90post.com/forums when N54 twin turbo engine just come out and from many2 dyno run by many-many people it matters what octane of gas to what power being produced; for example 93 octane produce more power than 91 (93 octane gas available in some southern states), the engine response even to race gas in triple digit octane. in case of N54 engine it takes almost 1/5 to 1/4 tank before the DME completely adjust to different fuel map and timing though so it's not instantaneous.


for me who drives around ~8000 miles annualy the saving is rather small,
7500/16 = 468.75 gallons, if I save $.11 per gallon by switching to 89 from 92 then per year I'll save $51.5625. I'll skip one sushi bar visit the entire year and call it good

[Big "J"]

I know this thread is focused on V8 engines. Are there any thoughts or recommendations for those of us with I6 engines using 87 or 89 regularly?

[motordavid]

Originally Posted by Big "J"

I know this thread is focused on V8 engines. Are there any thoughts or recommendations for those of us with I6 engines using 87 or 89 regularly?

There have been several threads on the 'which gas' topic...the responses range from "I only use this top tier gas brand" to quasi-technical discussions, to "it's a $70G car, so buy premo".

I have run every/any brand of gas I have encountered, and octane ratings from 93 to 87. I don't do technical tests, the 'apparent performance' is simply the seat of my pants, but I do keep careful mpg records. I am not obsessed about mpg in a 2 1/2 ton vehicle, just curious about mpg.

My best mpg/tank ranges have come on 89 octane, probably a summer blend vs winter, and with less to no ethanol; I've done a few 500+ mile tanks with that combo, in one day long trips. I have also had good results from crummy 87, especially on 600+ mile day long trips where that tank of low octane was run through the car in hours, in high speed highway cruising.

Purely anecdotal, but I have never been able to determine that the higher octane/big name juice gave any more 'performance' or better mpg. And, our 3.0 IL 6 X is going on 10 yrs old with 78k miles, and seems to run well and has been basically problem free over that decade.

I think many of us 'feel better' when we dump 91/93 gas into our cars, but I suspect the actual 'impact/effect' is minimal vs 89, on occasion...since few of us have test equipment in our front seats, and fewer of us can really discern differences in seat of the pants, and 'conditions' may play a part on how the ol'engine 'feels' that day. So it seems to me to be mostly mythical and a function of typical human senses condition, as to the 'premium/top gas brand effect'.

Do I save a few bucks running 89/87 on occasion? Yes...does saving a few bucks, or the real effect on performance, or engine systems potential debilitation matter? No to all above, imo. Would I run 87 in the X or, my Vette continuously, esp in daily stop and go, probably not, but that is 'emotional' too, imo.

The more technically astute here on the Board can explain about engine mgmt systems, etc., but few of us require full throttle on take offs, ala driving jet planes. Most of us stumble around in daily traffic, or take trips.
Even our ol' 3.0 has all the grunt I have ever needed in ~10 yrs of driving it, often loaded to the gunwales.

Obviously, the 'cost' of premo vs non-premo, over a year or even several years of ownership is not the main issue, even if the car headline writers would lead one to feel that dumping their 15 mpg car for a 30 mpg is the cure for one's financial ills. So, run what one likes and drive the sumbitch.
YMMV...
My 50Cts.
GL, mD

[TowX]

In my '97 E39 528 if I run 89 on the highway with no a/c there is no loss of power or fuel economy, or any gain. But get off the highway and turn on the a/c and the car feels like it lost 20 hp. So if I'm going on a several hundred mile trip in the winter I'll put in 89 for the highway, but not in the summer.

With my current 4.4 I was forced to put 89 octane in it once last summer. Was pulling my race car to MidOhio and pushed the tank capacity a bit too far and had to get off at the next available exit and fill up. Took 22.7 gallons so I was on fumes. The problem is that this Mobil station was out of 93 and I had to put in 89. I didn't get maybe two miles up the road and every time I accelerated hard (4500 lb trailer in tow) it surged and was way down on power. I suspect the surging was the knock sensor constantly retarding the timing to deal with the crappy octane. And even on the flat Rte 30 driving at 70, even in 5th it struggled to pull hills. Normally I get 11-11.5 mpg pulling my trailer on long trips. I was down to almost 9 with the low octane. I got 100 miles on a half a tank of that junk, stipped and pulled one of the 100 octane jugs off my trailer and added 5 gal of the really good stuff ($7.50 a gal unfortunately). Within a couple of miles I got my lost power back!! I figure I had created an octane of about 92.5 or 93. So I won't ever put anything but 92 or 93 in it now.

[Jordo]

Originally Posted by Buzzcut

I'm going to throw a hand grenade into this conversation...

I started mixing E85 into my gas. E85 is 105 octane, and costs $3.00 a gallon when 87 is $3.50 and 93 is $3.70.

I started with 4 gallons of E85, to get about 89 octane. Next tank was 5 gallons, getting me to about 90 octane. I'm going to build up to 7 gallons, which will be a little over 91 octane.

Right now, the tank is about 22% ethanol. At 7 gallons, it will be about 29%.

It is hard to say if there is a hit to mileage. We've had a very hard winter here in Chicago, very cold and snowy, and my mileage has been just awful. Unfortunately, I started mixing when the weather warmed up a bit, and it looks like my mileage improved. I'm sure that it has nothing to do with the ethanol, it's the weather.

I've mixed E85 with gas in my previous car (see my blog The Drunken Swede), so I have some experience with this. We shall see about reliability and durability using increased amounts of ethanol (it was not an issue on an '07 Saab for 15,000 miles of driving with 30% ethanol). I'm prepared to replace whatever needs to be replaced if it breaks.

You sure did throw a hand grenade into this!!! lol

Let me give a tid bit into my backround before I kick my $.02.

I was a motocycle mechanic for 12 years... 6 of those years I work at a proformance only shop... a "speed shop" is the street term. We made national level drag bikes that ran on everything from pump gas, to leaded gas, to alcohol and everything in between. We also were very successful at building motors used in Pro motocross racing. (me)

After saying that.... I personally have at least 100 hours of dyno time just testing diffrent fuels.
I made a spread sheet, and tested .25 of a gal of each of the 32 fuel blends that VPfuels offered for NHRA bike drag racing.

The results....

Hands down no contest, the more lead, the more I can push the limits, the "tighter" I can take it. Or technicly speaking, the tighter we take the squish area with out detecting detonation.(a thin area around the diameter of the pistion that has the smallest clearances...compressing the fuel/air the most)

So seeing that means you can cram more in it. I would grind a steeper angle in the cam lobe, and increase its lift as well, timing, blah, blah blah.

I say this to show I'm not just giving my opinion, I have come to this conclusion based on data.

Ethonal is one of the worst things you can put in your motor.....IMHO.

Why?

1) It burns hotter, but has a much slower expantion rate. (aka smaller explosion = less umph) Less umph, is less MPG.

2) Fuel with lead burns, Fuel with Ethonal "pops". The abrupt "pop" that Ethonal produces accelerates the wear on bushings, and pivot points. (lower rod bearings even more so)

3) Ethanol also leave a more corosive residue behind. (This is why your chrome exhaust tips get dirty so quick)

I tried to keep this as short as possible, but it is a complex subject, so sorry if I wasnt clear on somthing. Hit me up, if so.

So to recap... THE ONLY ADVANTAGE OF ETHANOL is that it keep U.S. money here. Not over seas. Ethanol is not only more expensive to produce then gas, it hikes the price of corn based foods up as well. Famers are tempted to grow fuel corn instead of corn for consuption. The fuel corn pays better, which up-sets the supply and demand scale of consumable corn.


Ok, thats my point. No Ethanol.

P.S. The Getty brand gas stations sells Ethanol FREE fuel only! Thats the only place I go. Good for 1.5 MPG better then 15% Ethanol. (about .03 more per gal)