Premium Gas?

[Moose]

Doesn't work out that way. I have run 87 octane (and it's that refomulated crap here in SE Wisconsin all year) without problems, although I clean it several times a year too...

 

[Jeff Discos]

It does mix. The octane rating is a rating based on the ratio of octanol to heptanol in the fuel. Octanol is a molecule that resists detonation/combustion, while heptanol does not resist detonation/combustion. More octanol = more detonation resistance = higher octane rating. Like mixes/dissolves in like, meaning the octanol/heptanol in 89 or 91 will mix together fine. And because they're a ratio, the average would be what you would get if you mixed it 50:50.

I actually remember some chemistry from my education, hope that helped.

 

[ayavner]

Just for morbid curiousity, I keep meticulous mileage records, as well as what brand, grade, etc. I normally go with either Chevron Premium or Shell Mid-grade. However, you might find this interesting... once I accidentally filled up wtih Chevron regular (87) - for some reason at the pump, the sign is bright red, so in my early morning fog I just picked that figuring it must be the Premium... anyway... when it was all said and done, that week I recorded the highest-ever mileage for my 01 disco II.... weird... so, i figure I am safe with Mid-grade and it has never caused me any problems. Once in awhile, a can of Seafoam in the tank and one thru the manifold, or even Chemtool B-12 has given me great results.

 

[markthecat]

Good answer on the octane/N-heptane levels Jeff. As a chemist myself I'm quite impressed. Maybe you have another career to fall back on. As far as ayavner's (the rover guru's response) maybe there is some truth to my previous post that oil company's dump the premium in reg and plus tanks.

 

[mddisco]

the higher octane allows higher compression engines to produce more energy.. the ping in an engine is an early warning to let you know your gas/engine are not converting properly in the cylinder chamber. the gas is igniting before the spark of sparkplug.. this is a bad thing....it can lead to big problems down the road...

As mentioned an earlier email there are not many gas stations in alaska that sell premium yet alone mid-grade beyond fairbanks or anchorage... you can cheat by using regular but once you hear the pings put supreme back in it or an octane boost from your local parts shop.

the state-side discovery was made to run on 92 and above.

it would be nice if they made the diesel as an option over here.

 

[tcosson]

Yes,I would love to have a diesel. The new jeep has that as an option... to bad it's not for the Cherokee, or even better something like the wrangler

 

[ColeCam]

It probably will be, Big brother says they are getting ready to allow more cleaner burning deisel, providing more opportunities for car makers to switch over. In '07? correct me if I am wrong

 

[joey]

hmmm 2 long years.... my question is why they don't offer incentives to switch to LPG like they do in Europe...?

 

[MightyMax]

is it bad to alternate using 87 and 91 octane? I figure it would save me money on gas if i filled with regular then premium...and back and forth.

 

[joey]

Basically it is all in how you take care of your vehicle, it doesn't matter if it is a land rover or any other make of vehicle. You have to remember that all vehicles have been tuned for a certain level of octane. The valves, timing, compression of the cylinders all play into how the engine is tuned. The ECU can change the timing to compansate for curtain fuels and they (LR or other companies) also set all of the above for different markets around the world. Will your vehicle run on less than 87 octane, the answer is yes, will it run at its best levels or get the best fuel economy, then the answer is no.

My wife Caravan has a rating of 87 octane, my Disco states 91 octane, my Buick states 89 octane. Will they run with the other levels, yes. How will they perform, that is all in how you drive, how well you take care of them and if you make any mods to the fuel, exhaust or air systems.

I am sure that this isn't the best explination, but I don't run less than Premuim in any vehicle I drive, but that is just me.... if fuel prices get to $3 or more, then I will look at either a more economical vehicle for a daily driver, or look into LPG or Diesel....

Just my thoughts for the morning.