| Fuel change
- Click HERE for Original Thread
|
| Escaper |
| Has anyone considered changing the chip in the computer with that of Honda's clone to inable the use of 85 octane fuel? |
|
|
| JL_SS |
quote:
Originally posted by Escaper
Has anyone considered changing the chip in the computer with that of Honda's clone to inable the use of 85 octane fuel?
If you are not towing or racing, then just use regular grade gas in your MDX instead. You might experience a slight power loss under extreme conditions but the knock sensors will prevent any damage. There are a lot of owners that use regular and there have been no reported problems. Do a search for regular vs premium. |
|
|
| deejay |
| I've never heard anything about the chip. I just bought mine and have always used 87 in it. No problems even though Acura doesn't reccomend it. |
|
|
| SRSEN1999 |
| I have never use anything lower than Octane 91 or premium gas, because Acura doesn't recommend anything below that. |
|
|
| nightguy |
In mountainous areas, I can't imagine why the engine would know the difference unless you spend more time at lower elevations. I thought that was the point of lower octane gas. Looking at your location, I have no idea what you do.
If you're closer to sea level more often than not, I'd stick with a minimum of 87, probably wouldn't go lower than 86. I don't think I've ever seen anything less than 86 myself. |
|
|
| Echo2625 |
quote:
Originally posted by Escaper
Has anyone considered changing the chip in the computer with that of Honda's clone to inable the use of 85 octane fuel?
85 octane??
I wouldn't use that in an old junker much less a MDX! 87 octane or normal regular gas is fine in most instances however.
I use 89 octane and it works great for me. |
|
|
| dj-mdx2 |
| Is there any significant savings advantage by switching? |
|
|
| TooHypper |
I have a friend who is a Certified Honda Mechanic and he explained to me about the 2003 Accord (I sold it) , witht the Fly by Wire throttle...the computer adjusts the ignition timming depending on Octane, I am not sure about the MDX but I would assume it is the same thing.
The accord would produce 10 more horses with 91 Octane.
Just my 2 cents |
|
|
| DaleB |
quote:
Originally posted by TooHypper
I have a friend who is a Certified Honda Mechanic and he explained to me about the 2003 Accord (I sold it) , witht the Fly by Wire throttle...the computer adjusts the ignition timming depending on Octane, I am not sure about the MDX but I would assume it is the same thing.
The accord would produce 10 more horses with 91 Octane.
Just my 2 cents
The FBW throttle should have no bearing on the octane rating or the performance of the engine.
But yes, the computer does adjust based on feedback from knock sensors. Again, compression ratio is the major factor in determining octane requirement. Not the only, but the major.
The Pilot and MDX are essentially the same mechanically. One recommends regular (Pilot) the other recommends premium.
This topic is discussed ad nauseum in several different threads over the years. In the meantime, there are still folks comfortably running regular and others running premium. So no real conclusion.
Or maybe we should call it a split-decision. |
|
|
| m2pc |
I think 87 is fine and the knock sensors should prevent damage. Just wondering though, do the premium gas contain higher amounts of additives for fuel injector cleaners? Just wondering because not sure of the effect of the ethanol/methanol adds in the gas these days.
I guess if it is a concern, could occassionally throw in some fuel injector cleaner. |
|
|
| EXCALIBUR |
quote:
Originally posted by m2pc
Just wondering though, do the premium gas contain higher amounts of additives for fuel injector cleaners?
There has long been a perception that higher octane gas is "better, higher quality, cleaner, etc." than lower octane gas. Like you, I just run the 87 octane gas, and my MDX runs fine.:4: |
|
|
| DaleB |
quote:
Originally posted by EXCALIBUR
There has long been a perception that higher octane gas is "better, higher quality, cleaner, etc." than lower octane gas. Like you, I just run the 87 octane gas, and my MDX runs fine.:4:
I agree. I don't think the grade vs. how much detergent makes any real difference these days. Since so many cars are now built with recommendations for regular fuel, it's like saying it's okay for their engines to be degraded sooner.
I don't see as many ads these days promoting that premium has more detergent.
Of course, if they advertise it does, it better. But it does not have to have much more. Just enough to keep the advertising legal and make it sound so good you want to drink it! :) |
|
|
| screbr |
quote:
Originally posted by Echo2625
85 octane??
I wouldn't use that in an old junker much less a MDX! 87 octane or normal regular gas is fine in most instances however.
I use 89 octane and it works great for me.
85 is available at every gas station out here at elevation. It is your "87". Our 3 choices are 85, 87 or 91.
I use the 87 (mid) in mine. |
|
|
| G. COLTON |
quote:
Originally posted by nightguy
In mountainous areas, I can't imagine why the engine would know the difference unless you spend more time at lower elevations. I thought that was the point of lower octane gas. Looking at your location, I have no idea what you do.
If you're closer to sea level more often than not, I'd stick with a minimum of 87, probably wouldn't go lower than 86. I don't think I've ever seen anything less than 86 myself.
I thinks maybe that you are just pulling our collective legs.
HIGHER and LOWER octane numbers have nothing to do with altitude.
.
G |
|
|
| Mr. Mom |
“HIGHER and LOWER octane numbers have nothing to do with altitude.”
Tell that to an aircraft mechanic. He’ll introduce you to the blower of hot air. |
|
|
| DaleB |
Per Chevron:
"Altitude - The higher the altitude above sea level, the lower the octane requirement. Modern computer-controlled engines adjust spark timing and air-fuel ratio to compensate for changes in barometric pressure, and thus the effect of altitude on octane requirement is smaller in these vehicles." |
|
|
| anjan |
quote:
Originally posted by DaleB
The Pilot and MDX are essentially the same mechanically. One recommends regular (Pilot) the other recommends premium.
I don't want to get into the entire question of saving a whopping $3 per tank by going down a grade, since I'm not sure I can handle that kind of fortune.
But that statement above is hilarious because of the amount of misinformation you have. Check my other post here that is from an interview with the Chief Engineer who designed the Pilot here. Remember that MDX came first. They took away a lot of things, and as you would see in the excerpt I posted, he talks about how numerous settings were changed to adapt the engine to run on 87 properly.
Now you might come up with an imaginative response to why the engineer has no clue but I just had to mention this because this is one my my pet peeves. Sure they share a lot of parts just like Highlander and RX330 do. Calling them "similar" is misinformed.... |
|
|
| DaleB |
quote:
Originally posted by anjan
I don't want to get into the entire question of saving a whopping $3 per tank by going down a grade, since I'm not sure I can handle that kind of fortune.
But that statement above is hilarious because of the amount of misinformation you have. Check my other post here that is from an interview with the Chief Engineer who designed the Pilot here. Remember that MDX came first. They took away a lot of things, and as you would see in the excerpt I posted, he talks about how numerous settings were changed to adapt the engine to run on 87 properly.
Now you might come up with an imaginative response to why the engineer has no clue but I just had to mention this because this is one my my pet peeves. Sure they share a lot of parts just like Highlander and RX330 do. Calling them "similar" is misinformed....
Spare the attitude, Anjan. It's not necessary to make a point.
I am not saying I doubt your source, but it might interesting to read the enitre 'article' if you could link or post it for all member's benefit on the forum.
It is very easy to overlook or forget a past discussion especially when the question comes up so often. Maybe it could even get front page notice as it is one of the most asked questions on the forum.
I don't purposely state misinformation, and will gladly accept corrections if a valid source is posted.
And calling them 'similar' is not misinformaton. Calling them the same would be (in this case). |
|
|
| DaleB |
quote:
Originally posted by socalJD
:lurk:
Oh go put away your popcorn! I am fair game for the next few days while I am out of town! Have a good week, y'all! (even Anjan). :D |
|
|
| anjan |
Not sure why you'd consider that "attitude." Just pointing out something that I see crop up often to justify miniscule savings and something that's not true.
Here's an article discussing the technologies in the Pilot, Odyssey, and MDX. As you go through, you'll see that Pilot and MDX have 65% similar parts. 35% is a lot of different parts.
In other words, if a MDX owner needs to penny pinch in order to survive, its fine. Its not my MDX so I could care less but to make assertions to justify why manufacturer's recommendations are not being followed, it gets a little funny. Again, no attitude. Just pointing out a rampant misconception I see in this thread. |
|
|
| DaleB |
quote:
Originally posted by anjan
Not sure why you'd consider that "attitude." Just pointing out something that I see crop up often to justify miniscule savings and something that's not true.
Here's an article discussing the technologies in the Pilot, Odyssey, and MDX. As you go through, you'll see that Pilot and MDX have 65% similar parts. 35% is a lot of different parts.
In other words, if a MDX owner needs to penny pinch in order to survive, its fine. Its not my MDX so I could care less but to make assertions to justify why manufacturer's recommendations are not being followed, it gets a little funny. Again, no attitude. Just pointing out a rampant misconception I see in this thread.
If it's a rampant misconception then obviously the right information is not widely known. Although I think most of us know it is a recommendation, and not a requirement. But you would be operating in the more effective range of the intended design by following it. I would not assume everyone's motive is based on penny pinching, etc. There could be other reasons like just stubborness, but I think misinformation is the biggest reason.
I am reluctant to assume anyone's motive for doing anything.
I don't find someone posting misinformation as 'hilarious'. I would simply correct them with the right information if available to me, and leave it at that.
Again, thanks for the link! It's good info! I know I will make every effort to reference it in the future for everyone's benefit when the opportunity presents itself on this topic. I probably will not have to wait long either! |
|
|
| nightguy |
quote:
Originally posted by DaleB
Per Chevron:
"Altitude - The higher the altitude above sea level, the lower the octane requirement. Modern computer-controlled engines adjust spark timing and air-fuel ratio to compensate for changes in barometric pressure, and thus the effect of altitude on octane requirement is smaller in these vehicles."
I guess I assumed everyone would know that but obviously I was wrong. Good explanation.
Like screbr said about 85. "It is your '87'. Which still makes me wonder why you'd need a chip if you stay at high elevations.
True modern engines can compensate, but why would you waste the money on high octane only to have the car make due with it ?
G.- Altitude certainly makes a difference in how gasoline is burned. Heck, you can't even turn cake mix into cake with the same cooking directions. Just read the back of the box. |
|
|
| DaleB |
quote:
Originally posted by nightguy
I guess I assumed everyone would know that but obviously I was wrong. Good explanation.
Like screbr said about 85. "It is your '87'. Which still makes me wonder why you'd need a chip if you stay at high elevations.
True modern engines can compensate, but why would you waste the money on high octane only to have the car make due with it ?
G.- Altitude certainly makes a difference in how gasoline is burned. Heck, you can't even turn cake mix into cake with the same cooking directions. Just read the back of the box.
Maybe the difference in lifestyle based on altitude should be called the 'Loftiness Factor'. :) |
|
|
| nightguy |
Found this on faqs.org It's interesting, no idea if it's 100% true.
What is the effect of altitude?
The effect of increasing altitude may be nonlinear, with one study reporting a decrease of the octane requirement of 1.4 RON/300m from sea level to 1800m and 2.5 RON/300m from 1800m to 3600m [27]. Other studies report the octane number requirement decreased by 1.0 - 1.9 RON/300m without specifying altitude [38]. Modern engine management systems can accommodate this adjustment, and in some recent studies, the octane number requirement was reduced by 0.2 - 0.5 (R+M)/2 per 300m increase in altitude.
The larger reduction on older engines was due to:-
- reduced air density provides lower combustion temperature and pressure.
- fuel is metered according to air volume, consequently as density decreases the stoichiometry moves to rich, with a lower octane number requirement.
- manifold vacuum controlled spark advance, and reduced manifold vacuum results in less spark advance. |
|
|
| screbr |
quote:
Originally posted by DaleB
Maybe the difference in lifestyle based on altitude should be called the 'Loftiness Factor'. :)
Also a term that could be used to describe a post from anjan.:2:
(just a light-hearted jab, not intended to offend....) |
|
|
| anjan |
quote:
Originally posted by screbr
Also a term that could be used to describe a post from anjan.:2:
(just a light-hearted jab, not intended to offend....)
Hey, potatoe - potato. I call it Pragmatism factor, you call it Loftiness. I guess its a compliment in a way. Thank you :2: :1: |
|
|
|
|
|
