using higher octane on v6

[phenixdragon]

Originally Posted by ptone

what scrming saying is accurate. i built a few cars some turbo some all motor. higher the octane the slower it burns. slower it burns cooler it is. cooler temps=more power and less knock. and u should always get better mpg with high octane,again becasue it burns slower.

Slower burns also mentions less combustion which also means less overall power. And high octane does not mean high MPG. You go with what it was designed for. Why not just put in 110 octane? According to your logic, we should be.

[GoPaul]

so has anyone done the fuse pull after switching to Premium ?

Link

Not sure if it would do anything for the V6, but I'd imagine the computer can't be too different...

[phenixdragon]

Originally Posted by Shadow II

I recommend the mid grade, Chevron or any other "cleaner" gasoline. I've tried all three for a spell, and prefer the mid grade. You can feel a difference.

You do realize that all gas stations (nearly), except for Chevon actually, tread between each other don't you? If one station is running low they will buy gas from their competitor. You could be going to Arco and filling up with gas from BP, or vis versa.

[DarkneSS]

Originally Posted by GoPaul

so has anyone done the fuse pull after switching to Premium ?

Link

Not sure if it would do anything for the V6, but I'd imagine the computer can't be too different...

+1 on this I'd really like to know.

[squat]

Where can I get one of those gizmos scrming used? I want to test this on my G8.

[Angrybird 12]

Originally Posted by GreenMonster

my question is will putting 91 (supreme) in my v6 or any regular gas car effect the engine LONG TERM???

the answer is No it won't harm your engine.

[2010SLVRBULIT]

higher altitude, our options are 85,87,91. With less air, 87 works great. Don't think I'd drop down to 85, though. 91 would be pointless for a n/a engine up here, imo.

[Angrybird 12]

Originally Posted by GoPaul

so has anyone done the fuse pull after switching to Premium ?

Link

Not sure if it would do anything for the V6, but I'd imagine the computer can't be too different...

there are tons of differences between the two. the engines are in no way the same other than they both are internal combustion engines... the v6 is an overhead cam direct injected engine. the V8 is a pushrod Multiport injected engine. I have read on here previously that the fuse pull method will not work on the V6 because it is not designed to be able to "sense the Octane" as the V8 Can ( and even that is just a quick method of the engine reseting it's self to the proper octane. If you leave it alone it would recalibrate it's self in a couple fuel refills anyway). The only change for the V6 will be is the Knock Sensor may not detect as much spark knock and allow a little more timing to be put into the motor thus producing the slight power increase people sometimes claim.

[The_Blur]

I hate to change sides on this issue, but having the knock sensors active at 87 and not at 89 indicates that there is an empirical benefit to using 89. This does not preclude that using higher octane in general is better for the engine, but there is enough evidence to suggest an upgrade to 89 might be worthwhile. Anything higher seems to have no additional benefit.

[phenixdragon]

Read back to what I said, higher may produce high power per combustion but over all there is less power comping out as it burns slow.

[Abygale]

Originally Posted by squat

Where can I get one of those gizmos scrming used? I want to test this on my G8.

That is a Dashhawk. I got mine from MSD Ignition:

http://www.msdignition.com/info.aspx...196&taxid2=204

I have been using 87 since I got my car. I'm going to hook up the Dashhawk on the way home tonight and monitor that knock sensor. I'm about out of gas so once I am, I will put in 91 and see if it makes a difference for me as well.

[Angrybird 12]

FYI, I found this information on Octane's effects.

Higher octane ratings correlate to higher activation energies. Activation energy is the amount of energy necessary to start a chemical reaction. Since higher octane fuels have higher activation energies, it is less likely that a given compression will cause autoignition.

It might seem odd that fuels with higher octane ratings are used in more powerful engines, since such fuels ignite less easily. However, an uncontrolled ignition is not desired in a spark ignition engine.

A fuel with a higher octane rating can be run at a higher compression ratio without causing detonation. Compression is directly related to power (see engine tuning), so engines that require higher octane usually deliver more motive power. Engine power is a function of the fuel, as well as the engine design, and is related to octane rating of the fuel. Power is limited by the maximum amount of fuel-air mixture that can be forced into the combustion chamber. When the throttle is partially open, only a small fraction of the total available power is produced because the manifold is operating at pressures far below atmospheric. In this case, the octane requirement is far lower than when the throttle is opened fully and the manifold pressure increases to atmospheric pressure, or higher in the case of supercharged or turbocharged engines.

Many high-performance engines are designed to operate with a high maximum compression, and thus demand high-octane premium gasoline. A common misconception is that power output or fuel mileage can be improved by burning higher octane fuel than a particular engine was designed for. The power output of an engine depends in part on the energy density of its fuel, but similar fuels with different octane ratings have similar density. Since switching to a higher octane fuel does not add any more hydrocarbon content or oxygen, the engine cannot produce more power.

However, burning fuel with a lower octane rating than required by the engine often reduces power output and efficiency one way or another. If the engine begins to detonate (blow up), that reduces power and efficiency for the reasons stated above. Many modern car engines feature a [knock sensor] – a small piezoelectric microphone which detects knock, and then sends a signal to the engine control unit to retard the ignition timing. Retarding the ignition timing reduces the tendency to detonate, but also reduces power output and fuel efficiency.

Most fuel stations have two storage tanks (even those offering 3 or 4 octane levels), and you are given a mixture of the higher and lower octane fuel. Purchasing premium simply means more fuel from the higher octane tank; the detergents in the fuel are often the same.

By the way someone else had mentioned it before but the higher the altitude you drive at the less effect of going to a higher octane fuel will have. so the ones that live in lower altitude areas will probably feel the difference while someone living in a high altitude area may not feel or see any difference... I live in the Mountians of East Tennessee and tried all 3 grades, I really could not tell any difference at all...other than it cost about 4 bucks more to fill up on premimum.....I could have bought another gallon and a half of regular...

[Abygale]

If you are going to "cut and paste" it would be very helpful if you would link the source of the information as well. Thank you!

[Angrybird 12]

Originally Posted by Abygale

If you are going to "cut and paste" it would be very helpful if you would link the source of the information as well. Thank you!

I'll go back and see where it was, I got it from Wiki...
But I read several articals from different sources all seemed to have the same info, and this summed it up better..