Premium gas only for the XK8s?
#21
Any time a member is deleted or removed he "inherits" your garage. It just seems to be the way the system works. To me it looks like he has my garage.
#23
back to the octane topic.... since performance is lower with low octane, and some "traffic issues" required acceleration to avoid mishap, I would prefer to spend and extra $200/year using premium, and know that the car can always get out the traffic situation quickly. Same goes for my motorcycle.
alfred
alfred
#24
I ran leaded fuel in my Alfa Romeo track car, which I purchased at the race track itself, but a few of the local stations also offered the stuff.
I ran my 97 Vanden Plas on mid-grade unleaded fuel (89 octane) many times without any problems whatsoever. If I have to I will run my 07 XK on mid-grade, but knowing about some funky Jag issue with water in the gas tank, which requires "dry gas" treatments periodically, I will try to avoid 1) letting the tank get below 1/4 and 2) using less than premium unleaded.
It is my understanding from an article I read several years ago that all modern engine computers are designed to detect the octane level of the gas and alter ratios accordingly, including MPG and HP. However, in most cases, using lower octane fuel will cause only a 2-3 HP reduction.
I ran my 97 Vanden Plas on mid-grade unleaded fuel (89 octane) many times without any problems whatsoever. If I have to I will run my 07 XK on mid-grade, but knowing about some funky Jag issue with water in the gas tank, which requires "dry gas" treatments periodically, I will try to avoid 1) letting the tank get below 1/4 and 2) using less than premium unleaded.
It is my understanding from an article I read several years ago that all modern engine computers are designed to detect the octane level of the gas and alter ratios accordingly, including MPG and HP. However, in most cases, using lower octane fuel will cause only a 2-3 HP reduction.
#25
Join Date: Oct 2009
Location: Perth Ontario Canada
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.... If I have to I will run my 07 XK on mid-grade, but knowing about some funky Jag issue with water in the gas tank, which requires "dry gas" treatments periodically, I will try to avoid 1) letting the tank get below 1/4 and 2) using less than premium unleaded.
It is my understanding from an article I read several years ago that all modern engine computers are designed to detect the octane level of the gas and alter ratios accordingly, including MPG and HP. However, in most cases, using lower octane fuel will cause only a 2-3 HP reduction.
It is my understanding from an article I read several years ago that all modern engine computers are designed to detect the octane level of the gas and alter ratios accordingly, including MPG and HP. However, in most cases, using lower octane fuel will cause only a 2-3 HP reduction.
No car I am familiar with has a system for detecting octane levels, nor does it alter 'ratios'. As stated many times previously, if detonation (pinging/knocking) is detected via the knock sensors, the spark timing is retarded from it's standard setting until the detonation ceases.
If the engine is not being operated in such a manner as to induce detonation, then full spark advance is resumed and full power and economy can be expected irrespective of a low octane rating.
Sounds like you've read some misleading info.
#26
Speaking of water in the gas tank, I would think that it wouldn't be a problem these days since the gas contains a certain amount of ethanol. Water can't dissolve in gasoline, but it can dissolve in alcohol. If you have water in your tank, the solution is to put alcohol in the tank to absorb the water. The water is then distributed amongst the alcohol and it doesn't hit the engine in big globs.
Having said that, I had a problem with water in the fuel this past summer. I got some bad gas at a gas station in the middle of nowhere.
Having said that, I had a problem with water in the fuel this past summer. I got some bad gas at a gas station in the middle of nowhere.
#27
leaded fules... DO NOT DO IT!
DO NOT USE LEADED FUEL! it will damage the cats! unless you want to buy a set of Namless Performance Cat delete pipes then go for it!
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