witch octane gas do you run
- Thread starter bell9440
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GrayGhost1
Guest
The LS was designed to run on at least 91 octane fuel. It states it very clearly in the owner's manual. The LS has a very high compression engine and using anything less will only cause long term problems. Also, there normally isn't but a 20 cent difference in regular and premium at most pumps so you're only talking about a $3.20 - $3.50 difference in total fuel costs per fill up. That doesn't seem a lot to me for having a car running on the required fuel.
Also, the check engine light will come on too from not completely tightening the gas cap. I had this happen to me once. The CEL could mean a numerous things too. I wouldn't rule out other issues too like a bad O2 sensor or similar.
Also, the check engine light will come on too from not completely tightening the gas cap. I had this happen to me once. The CEL could mean a numerous things too. I wouldn't rule out other issues too like a bad O2 sensor or similar.
Slow91z
Active LVC Member
I run 89 oct. all the time.
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GrayGhost1
Guest
There you have it.SoonerLS said:
You can get away with running 89 octane, but their'll be less power under full throttle and passing. It works fine for light city driving and highway cruising. NEVER RUN 87. It's like trying to destroy your engine.
daves2000ls
Dedicated LVC Member
the previous owner of my ls apparently ran 87 and carbon built up in my exhaust and the CEL stayed on for weeks
ohioLS
Dedicated LVC Member
BP 93 or Shell V-Power is all I run.
Jim Henderson
Dedicated LVC Member
I got my 2004 LS V8 with 14,000 miles on it. Since then I have put on about 12,000 miles, most of it with 89 octane. The engine has not blown up. I worry more about the tranny than I do the engine.
I have run 87 and it will ping pretty good on a warm day with moderate to hard acceleration. I even think I can feel the computer pull back the timing under hard acceleration to lessen the ping.
With 89 I almost never get ping. The only time I get ping and it is just noticable, is with hot weather under load. Situations like hot weather, AC on and climbing a steep hill(30 degress?) at 25mph in 4th or 5th will do it. I rarely get ping under hard accelaration alone, almost can't recall any situations where I did. I am one of those who likes to do several full throttle rolling start accelerations to freeway speed several times a day and then most of my driving is steady cruising. The cruising is less octane intensive. Accerlation requires more octane for best performance.
91 as the manual states is the safest choice. 89 appears to work in my car. Not all cars are the same. Carbon buildups due to sluggardly driving habits have been known to increase the tendency to ping. Also older cars will ping easier, and some engines just ping.
Interestingly I appear to get the best mileage with 89. I can drive with 91 for a few tankfuls and get OK mileage. Then when I switch to 89 I get maybe 1mpg more on my commute. I average about 20+mpg on my 30mile one way commute, averaging 70mph+ in the morning and maybe 60+ with a short stretch of stop and go in the evening.
I have run all of my previous "performance" cars on either 87 or 89 with no bad results(several over 100K miles). Some cars did like 89 or 91 more in summer. My 94 F250 is spec'd to run on 87 but likes 89-91 when towing 8000# in hot weather. Cold weather it runs fine on 87. Ping depends on load and engine condition among other things.
The engine computer is supposed to adjust timing to work with the gas you have. Using lower octane decreases the flexibility the computer has so you might get ping under certain conditions. For those of you who drive sedately lower octane probably will work fine. For those who like to drive aggressively then you need the margin of 91+.
The price difference in gas doesn't really make a whole lot of sense for us. I drive my LS about 15000 per year averaging 20mpg. That means I burn about 750 gallons per year. At 10 cents per gallon between 89 and 91 that means I save a whopping $75 per year. Not a whole lot in comparison to maybe $1900 per year in gas. But I am cheap and like to drive with "adequate" octane for my style of driving, plus as mentioned I get about 1mpg more from 89, and again I am cheap.
To be safe use 91. If your car works well with it, you can use 89. I would probably not use 87 except in a pinch. Make your own choice and live with the results.
YMMV,
Jim Henderson
I have run 87 and it will ping pretty good on a warm day with moderate to hard acceleration. I even think I can feel the computer pull back the timing under hard acceleration to lessen the ping.
With 89 I almost never get ping. The only time I get ping and it is just noticable, is with hot weather under load. Situations like hot weather, AC on and climbing a steep hill(30 degress?) at 25mph in 4th or 5th will do it. I rarely get ping under hard accelaration alone, almost can't recall any situations where I did. I am one of those who likes to do several full throttle rolling start accelerations to freeway speed several times a day and then most of my driving is steady cruising. The cruising is less octane intensive. Accerlation requires more octane for best performance.
91 as the manual states is the safest choice. 89 appears to work in my car. Not all cars are the same. Carbon buildups due to sluggardly driving habits have been known to increase the tendency to ping. Also older cars will ping easier, and some engines just ping.
Interestingly I appear to get the best mileage with 89. I can drive with 91 for a few tankfuls and get OK mileage. Then when I switch to 89 I get maybe 1mpg more on my commute. I average about 20+mpg on my 30mile one way commute, averaging 70mph+ in the morning and maybe 60+ with a short stretch of stop and go in the evening.
I have run all of my previous "performance" cars on either 87 or 89 with no bad results(several over 100K miles). Some cars did like 89 or 91 more in summer. My 94 F250 is spec'd to run on 87 but likes 89-91 when towing 8000# in hot weather. Cold weather it runs fine on 87. Ping depends on load and engine condition among other things.
The engine computer is supposed to adjust timing to work with the gas you have. Using lower octane decreases the flexibility the computer has so you might get ping under certain conditions. For those of you who drive sedately lower octane probably will work fine. For those who like to drive aggressively then you need the margin of 91+.
The price difference in gas doesn't really make a whole lot of sense for us. I drive my LS about 15000 per year averaging 20mpg. That means I burn about 750 gallons per year. At 10 cents per gallon between 89 and 91 that means I save a whopping $75 per year. Not a whole lot in comparison to maybe $1900 per year in gas. But I am cheap and like to drive with "adequate" octane for my style of driving, plus as mentioned I get about 1mpg more from 89, and again I am cheap.
To be safe use 91. If your car works well with it, you can use 89. I would probably not use 87 except in a pinch. Make your own choice and live with the results.
YMMV,
Jim Henderson
Jibit
Dearly Departed Friend
People complain about the price of gas but I've heard comparison on the mileage and it usually equals out or comes close. Basically you get better mileage with the better gas so the difference in cost cancels out.
Slow91z
Active LVC Member
dsoul27 said:
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GrayGhost1
Guest
QUIT THAT! I'M TRYING TO WORK!!Slow91z said:
When I first got the car in dec. '04 I put alittle of the cheap stuff in it on my way home. Car sucked the stuff down pretty fast and than I found out it required 91+ after reading the manual and not to mention there is a sticker I found out my second fill up that says it takes 91+on the lil' gas door, so I put in 93 because that is the premium grade around here and have ever since. Price annoys me but only cause one day prem. will be 2.15 and the day I go to get some its back up to 2.30+. Other than that I do not give a crap, I bought the car, wanted the v8, so I put what it needs. I use shell v-power, used to do exxon but it started to seem weird acting and I went and got shell and it seemed to smooth out.
I believe I did use 89 once and it was alright, did not notice much besides the lack of power.
I believe I did use 89 once and it was alright, did not notice much besides the lack of power.
Well now that we have the octane issue settled, does anyone know which brand is supposed to be best? I know on the Corvette forum everyone swears my Chevron because of the additives so that's what I use in the vette. Haven't really settled on a specific type in the LS.
Take it from me man, I went all over the place trying different octanes. Ironic how I replaced the coil packs so much and had so many hard start up problems. RUN 91+, I run 93 and haven't had a problem since.
BMW, GM, Toyota, and Honda have put together a "top tier" gas Web site ( http://www.toptiergas.com/ ) that list their "Top Tier" certified gas vendors.ltnate3 said:
I can tell you that I got significantly better mileage using Conoco (which is a "Top Tier" brand) than I did using 7-11 gas. My dad had the same experience when he had to make round trips from OKC to Amarillo--with Conoco gas, he would make it with miles to spare, but with the cheap 7-11 gas, he would have to stop for gas in El Reno on the return trip.
FWIW, Ford has apparently made a deal with BP-Amoco, and some of the new cars are supposed to have "Ford recommends BP gas" stickers inside the gas door. Interestingly, they're not listed as one of the "Top Tier" brands...
As far as Chevron goes, my LS liked it the one time I filled up with it. We don't have Chevron stations around here; the closest place with it is North Texas, but their price for regular unleaded (remember when that was an oxymoron?) is normally higher than our price for premium, so I don't buy gas down there very often. Once, however, not long after Katrina hit, the price at the Chevron in Denton was the same as the Conoco in Norman where I usually fill up, so I filled up with Chevron, and my gas mileage was almost 2mpg higher than normal for the trip.
I normally get better gas mileage going north from DFW, so it may not have been the Chevron gas, but I still think it was a bit higher than normal...