| Is premium gas a must?
- Click HERE for Original Thread
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| anjan |
quote:
Originally posted by frainc
I now have been putting in 87 for close to two months now and I don't feel no lost in power or hear or feel any detonation in the motor.
:2: This one always kills me. With the amount of insulation that's in a luxury SUV like MDX, along with the computer detecting and eliminating the engine knocking, even a trained professional race car driver will not be able to "tell the difference". At a minimum your engine is going through a few knocks at every gas fill.
quote:
I know what the manual tells you but until the price of gas goes down, then its 87 for me.
News Flash. Gas prices are relative. No matter what, I pay 20 cents more per gallon than you. Even if its $6 a gallon for regular, I'll pay 20c more per gallon only. Even compared to 87, I'm paying a WHOPPING $3.00 more per tank :eek:
I don't think any of the "camps" here have ever conceded an inch of ground. The issue here is not what the MDX can run on. Its an inherent inferiority complex about owning a luxury car that is not expensive enough (I have friends that drive their BMW and Lexus on 87, and they claim it runs "absolutely fine"). Hence some of us here say Acura's engineers are liars and don't know anything about combustion systems. The rest of us are leaving automotive engineering to the ones we trusted enough to shell out major bucks and get their creation.
Its not octane rating, its personality type. I see lots of people that would try to go see the "best doctor" for a higher price and then second guess their diagnosis and medication. |
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| Ronsully |
quote:
Originally posted by anjan
:2: This one always kills me. With the amount of insulation that's in a luxury SUV like MDX, along with the computer detecting and eliminating the engine knocking, even a trained professional race car driver will not be able to "tell the difference". At a minimum your engine is going through a few knocks at every gas fill.
News Flash. Gas prices are relative. No matter what, I pay 20 cents more per gallon than you. Even if its $6 a gallon for regular, I'll pay 20c more per gallon only. Even compared to 87, I'm paying a WHOPPING $3.00 more per tank :eek:
I don't think any of the "camps" here have ever conceded an inch of ground. The issue here is not what the MDX can run on. Its an inherent inferiority complex about owning a luxury car that is not expensive enough (I have friends that drive their BMW and Lexus on 87, and they claim it runs "absolutely fine"). Hence some of us here say Acura's engineers are liars and don't know anything about combustion systems. The rest of us are leaving automotive engineering to the ones we trusted enough to shell out major bucks and get their creation.
Its not octane rating, its personality type. I see lots of people that would try to go see the "best doctor" for a higher price and then second guess their diagnosis and medication.
You are crazy man..... just crazy.... :2: Don't you know that by putting in 87 versus 91-93 these people will have the 3 dollars to buy a venti mocha latte..
Good luck to everyone that uses 87 octane. I wonder if a compression test or leak down test would show any damage with the 87 octane users.:D |
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| anjan |
quote:
Originally posted by Ronsully
Good luck to everyone that uses 87 octane. I wonder if a compression test or leak down test would show any damage with the 87 octane users.:D
:4: I'm noting this in my mind...I really wouldn't want to buy a used MDX. Who knows - someone tried to run it on Vaseline maybe? Of course, for the brave a confident that have been supposedly running 87 for years, a simple trip to a diagnostic shop will answer that question. I'd get a kick out of seeing the compression numbers on the pistons - it'll be a mess. For $50 (I know that's unthinkable who are saving $3.00 per tank) will really tell you what extended use of regular fuel has wrought on the pistons and emissions. |
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| socalJD |
quote:
Originally posted by anjan
. . . will really tell you what extended use of regular fuel has wrought on the pistons and emissions. . .
Then can you explain how Odysseys & Pilots run 87 octane and drive forever and ever ? Let's see, Odysseys debuted in 1999, and haven't heard of a motor blowing up yet - certainly wouldn't be a CR recommended and top 10 pick if they had chronic motor failure due to cheap gas . . . |
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| anjan |
quote:
Originally posted by socalJD
Then can you explain how Odysseys & Pilots run 87 octane and drive forever and ever ? Let's see, Odysseys debuted in 1999, and haven't heard of a motor blowing up yet - certainly wouldn't be a CR recommended and top 10 pick if they had chronic motor failure due to cheap gas . . .
And neither has Corolla's engine. Or Accord's? So what does that have to do with MDX?
Before you jump up and down -
1. MDX is NOT Odyssey or Pilot. Same platform doesn't mean everything is same.
2. Like I said - the issue here is not octane rating - its the tendency of some to think that Acura's engineers don't know s**t or they are incorrigible liars. |
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| nightguy |
quote:
Originally posted by EXCALIBUR
The original topic of this thread was,"Is premium gas a must?" The test run by QRTLOW found that the mileage from 87 octane gas was in this case actually higher than the more expensive 91 octane gas. Therefore a case has been made that premium gas is not a must.:ucrazy:
I can't think of a better way to put it. :4: |
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| socalJD |
quote:
Originally posted by anjan
1. MDX is NOT Odyssey or Pilot. Same platform doesn't mean everything is same.
2. Like I said - the issue here is not octane rating - its the tendency of some to think that Acura's engineers don't know s**t or they are incorrigible liars. . .
How much deeper would you like to insert your foot ?
Yes, the MDX is not an Odyssey or Pilot, but guess what, they all share the same basic engine ! Check out the bore & stroke, compression ratio, valvetrain - IDENTICAL. One can argue that the MDX engine is tuned slightly different to justify the extra 10HP, but I doubt it - probably has more to do with the improved exhaust system. The '02 MDX was only rated at 240hp and the current Pilot is at 255. Not suggesting that the Acura engineers are liars, I think its a marketing shell game to differentiate the MDX as a premium brand. I.E. Lexus = premium gas, Toyota = regular gas. But don't kid yourself, the engine in the Pilot is not significantly different than that in the MDX, at least not to suggest that if a Pilot can safely run on 87 octane, the MDX can not. But ultimately, like most have said, its a personal preference, and to each their own . . . |
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| Ronsully |
I guess a lot of you do not understand
"Octane has little to no effect of gas mileage"
Of course the MDX will run on 87 octane... Hell it will run on 80 octane. However, you will ruin your engine. Gas Mileage has nothing to do with octane and everything to do with pre-ignition.
Does everyone at least agree with the above statement? |
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| DaleB |
A 3rd possibility:
Or maybe the Honda engineers are lying or deceiving when they make recommendations for the Pilot, and but dead on with the MDX. :rolleyes:
But it's okay, most of us agree, the MDX will run just fine with 91 octane. In fact, spend more, and make it 93 to be sure! |
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| anjan |
4th option - You blindly throw stuff and hope something will stick. If you're so confident - call Acura and ask them precisely why MDX "needs" 91 instead of grabbing things out of air. Same engine block can be tuned completely differently.
Here's what I got from Acura - the engine has been tuned to take advantage of higher octane - meaning the ignition timing default is set to 91+. The gain in hp from pure octane is around 5hp. Combined with a better exhaust system, that's the difference in hp between Pilot and MDX. Since the discussion is seemingly getting obtuse, let me make it clear enough for a three year old - you can TUNE your engine to take advantage of higher octane. Conversely, for you eternal satisfaction get it tuned to burn kerosene. It is NOT the same engine. Ron Sully can attest to the tuning ability of cars to adjust for performance.
What you are saying is that both you and I have one heart, two eyes etc etc so you and I are exactly the same. Now let's see how much you open your mouth and prove what I'm assuming about you :) |
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| socalJD |
quote:
Originally posted by anjan
4th option - You blindly throw stuff and hope something will stick. If you're so confident - call Acura and ask them precisely why MDX "needs" 91 instead of grabbing things out of air. Same engine block can be tuned completely differently.
Here's what I got from Acura - the engine has been tuned to take advantage of higher octane - meaning the ignition timing default is set to 91+. The gain in hp from pure octane is around 5hp. Combined with a better exhaust system, that's the difference in hp between Pilot and MDX. Since the discussion is seemingly getting obtuse, let me make it clear enough for a three year old - you can TUNE your engine to take advantage of higher octane. Conversely, for you eternal satisfaction get it tuned to burn kerosene. It is NOT the same engine. Ron Sully can attest to the tuning ability of cars to adjust for performance.
What you are saying is that both you and I have one heart, two eyes etc etc so you and I are exactly the same. Now let's see how much you open your mouth and prove what I'm assuming about you :)
Hmmm, let me get this straight. You called AHC and spoke to a CS rep just to support your opinion. I imagine the call went like this:
AHC: Good Afternoon. Please be advised that this phone conversation may be recorded to assist in customer service and future training for American Honda employees . . .
You: Hi, I need your help. Please give me some expert information to refute this guy on an internet chat site that I belong to who doesn't buy into my opinions.
AHC: I'll be glad to sir, what seems to be the problem.
You: Well this guy is saying that the MDX & Pilot have the same engine, and the only reason Acura is saying to use premium gas is to promote their upscale brand image.
AHC: Sir, I will have to consult our technical group since this is a specific question for which I don't have the usual canned, scripted, customer service response . . . please hold. (wave music playing in the background)
You: (thinking to self) I'll show that smooty know-it-all to never question my unqualified, unsupported personal opinions again.
AHC: Sir, after consulting the technical group, I can asure you that Acura would surely never do such a thing. Your superbly engineered and crafted MDX engine differs in so many ways from the Honda Pilot & Odyssey engines. For instance . . .
You get the drift. Congratulations. You win. I would blindly and wholeheartedly believe everything that I hear from a 3rd party telemarketing group contracted by AHC over the phone. What was I thinking ??? :rolleyes: |
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| DaleB |
Let's see, if I burn 91 to eek out another 5 hp at WOT.. wonderful things will happen.
But if I decide to forgo the 5 hp for 87 or 89 octane, my engine will crumble.
Did Acura tell you that too, or just half the story?
Have to admit, compared with all the previous threads on the subject (and there were many) this has gone from boring to ridiculous.
At least ridiculous is not boring....
:lurk: |
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| EXCALIBUR |
quote:
Originally posted by socalJD
Hmmm, let me get this straight. You called AHC and spoke to a CS rep just to support your opinion. I imagine the call went like this:
AHC: Good Afternoon. Please be advised that this phone conversation may be recorded to assist in customer service and future training for American Honda employees . . .
You: Hi, I need your help. Please give me some expert information to refute this guy on an internet chat site that I belong to who doesn't buy into my opinions.
AHC: I'll be glad to sir, what seems to be the problem.
You: Well this guy is saying that the MDX & Pilot have the same engine, and the only reason Acura is saying to use premium gas is to promote their upscale brand image.
AHC: Sir, I will have to consult our technical group since this is a specific question for which I don't have the usual canned, scripted, customer service response . . . please hold. (wave music playing in the background)
You: (thinking to self) I'll show that smooty know-it-all to never question my unqualified, unsupported personal opinions again.
AHC: Sir, after consulting the technical group, I can asure you that Acura would surely never do such a thing. Your superbly engineered and crafted MDX engine differs in so many ways from the Honda Pilot & Odyssey engines. For instance . . .
You get the drift. Congratulations. You win. I would blindly and wholeheartedly believe everything that I hear from a 3rd party telemarketing group contracted by AHC over the phone. What was I thinking ??? :rolleyes:
I like that.:29: |
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| EXCALIBUR |
quote:
Originally posted by DaleB
Let's see, if I burn 91 to eek out another 5 hp at WOT.. wonderful things will happen.
But if I decide to forgo the 5 hp for 87 or 89 octane, my engine will crumble.
Did Acura tell you that too, or just half the story?
Have to admit, all the previous threads on the subject (and there were many) have gone from boring to ridiculous.
At least ridiculous is not boring....
:lurk:
Don't touch that dial.:20: |
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| maohaohan |
I just read the fine print in the 05 MDX brochure, it said that with reduction of perfomance, you can use the 87 or 89 gas.
Just my 2 cents, use what ever gas you like, as long as it is unlead, and be persistent, I heard people say that change the grade level cause different size carbon particle in your engine, but that may be a myth. |
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| DaleB |
quote:
Originally posted by maohaohan
I just read the fine print in the 05 MDX brochure, it said that with reduction of perfomance, you can use the 87 or 89 gas.
Just my 2 cents, use what ever gas you like, as long as it is unlead, and be persistent, I heard people say that change the grade level cause different size carbon particle in your engine, but that may be a myth.
When they got the lead out and improved engine oils as well as fuels, deposits became less of an issue.
That does not mean it's wise to burn inferior quality fuel (no relation to octane) or not perform regular oil and filter changes.
Modern engines also run at much higher temperatures to control emissions, warming up faster and have more complete combustion. All these things further reduce the formation of deposits which were more common in older vehicles, especially in stop and go driving. There is some support that changing brands of detergents, by periodically changing fuel brands, does help in keep the fuel system cleaner.
The theory being some additives work better on specific deposits.
http://vettenet.org/octane.html |
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| frainc |
quote:
Originally posted by SuperTech
[B]There is more energy in lower octane fuels, so technically, 87 octane is more efficient than 92/91 octane.
All Auras are reccomended to run on premium unleaded. You can run 87 and get away with it probably forever. If you live in a cool climate, you'll never notice a difference. But if the weather gets warm, you may notice a ping for a moment when you give it some throttle. But the knock sensor will pick it up and retard the timing (robbing horsepower) until it doesn't ping anymore. You may not notice this at all. We're talking maybe losing 10-15hp or so.
Since SuperTech works at Acura, I believe he knows this engine alot better than most of us. And if he tells you that it will not harm this motor, then so be it. And its more than $3 per tank fill, something like $7-8 diff. when putting in 15 plus gals.
Hell on Long Island, I just got my elect. bill for $528 for two months usage, ****, they added a $108 fuel surcharge to my bill because they have to pay for higher oil themselves. I need to save $$$ where I can these days. |
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| xfactor |
quote:
Originally posted by DaleB
Let's see, if I burn 91 to eek out another 5 hp at WOT.. wonderful things will happen.
But if I decide to forgo the 5 hp for 87 or 89 octane, my engine will crumble.
Did Acura tell you that too, or just half the story?
Have to admit, compared with all the previous threads on the subject (and there were many) this has gone from boring to ridiculous.
At least ridiculous is not boring....
:lurk:
As usual, you summed it up perfectly...
:19: |
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| JL_SS |
quote:
Originally posted by DaleB
Let's see, if I burn 91 to eek out another 5 hp at WOT.. wonderful things will happen.
But if I decide to forgo the 5 hp for 87 or 89 octane, my engine will crumble.
Did Acura tell you that too, or just half the story?
Have to admit, compared with all the previous threads on the subject (and there were many) this has gone from boring to ridiculous.
At least ridiculous is not boring....
:lurk:
But given Acura's tranny record, that 5 hp reduction may just increase your tranny life tremendously...:D . |
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| anjan |
quote:
Originally posted by socalJD
Hmmm, let me get this straight. You called AHC and spoke to a CS rep just to support your opinion. I imagine the call went like this:
AHC: Good Afternoon. Please be advised that this phone conversation may be recorded to assist in customer service and future training for American Honda employees . . .
You: Hi, I need your help. Please give me some expert information to refute this guy on an internet chat site that I belong to who doesn't buy into my opinions.
AHC: I'll be glad to sir, what seems to be the problem.
You: Well this guy is saying that the MDX & Pilot have the same engine, and the only reason Acura is saying to use premium gas is to promote their upscale brand image.
AHC: Sir, I will have to consult our technical group since this is a specific question for which I don't have the usual canned, scripted, customer service response . . . please hold. (wave music playing in the background)
You: (thinking to self) I'll show that smooty know-it-all to never question my unqualified, unsupported personal opinions again.
AHC: Sir, after consulting the technical group, I can asure you that Acura would surely never do such a thing. Your superbly engineered and crafted MDX engine differs in so many ways from the Honda Pilot & Odyssey engines. For instance . . .
You get the drift. Congratulations. You win. I would blindly and wholeheartedly believe everything that I hear from a 3rd party telemarketing group contracted by AHC over the phone. What was I thinking ??? :rolleyes:
Thanks for proving my point without a shred of doubt. Welcome to the club of "I have a Ph.D. in Automotive Engineering from MIT" and Acura engineers are liars :) Makes me wonder why you are buying cars from such glib people. With your script writing skills, you must've won a few oscars by now. Go buy a Porsche or something.
Like many others are saying, this is not a question of which octane to use - that's a stupid question. Its the inherent nature of some people to challenge facts without any education in the matter whatsoever. Hey, there's internet - who needs degrees. I'll Google my way to nirvana :2: Its asinine that people don't read comments and come back to the "right octane" issue. This is my last response - bark away at how you can run MDX on sewage water or diet Coke.... |
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| SuperTech |
This is entertaining to say the least. So let me put my two cents in on what I've read in the past few pages.
quote:
Originally posted by Ronsully
I wonder if a compression test or leak down test would show any damage with the 87 octane users.:D
I doubt there'd be any difference if you drove the same with premium or regular unleaded. The amount of deposits left on the piston, valves, and combustion chamber have much more to do with driving style and quality of gas used. Chevron is arguably the best quality gas out there. Their Techron additive is in my opinion the best one of all the gasolines. And unlike Shell...they put this additve in all three grades. So if you used Chevron, no matter the grade...you'd have less deposts than if you had been tanking up at Arco all this time. Also...someone who is doing full throttle pulls on a regular basis isn't going to have many carbon desposits vs. someone who drives like there's an egg under the throttle. Ever see that initial poof of black smoke from the back of a car when someone gives it the whip? That's carbon built up in the combustion chamber goign bye bye.
quote:
Originally posted by socalJD
One can argue that the MDX engine is tuned slightly different to justify the extra 10HP, but I doubt it - probably has more to do with the improved exhaust system.
You could argue if you want...but you'd lose that one. While the motors are mechanically the same, the ECU in the MDX is programmed to allow more timing advance, giving more power...because they are assuming that since you had the coin for a luxury brand vehicle (ok...near luxury), you've got the money to afford the expensive gas too.
quote:
Originally posted by Ronsully
Gas Mileage has nothing to do with octane and everything to do with pre-ignition.
Does everyone at least agree with the above statement?
That's somewhat true. Octane and fuel mileage can be related. But mileage is also dependant on the engine making a clean burn. If detonation or pinging occurs...the computer will retard timing. Retarding the timing lowers the efficiency of the combustion of the fuel charge, which in turn reduces fuel economy. But...by using a higher octane, you can counteract the possibility of pre-ignition. And if there's no pre-ignition, the computer will allow the most efficient timing curve, which in turn gives you better mileage.
quote:
Originally posted by frainc
Since SuperTech works at Acura, I believe he knows this engine alot better than most of us. And if he tells you that it will not harm this motor, then so be it.
I'm telling you that you won't damage the motor. And even if it does blow up, how could I ever prove that it was bad gas that blew it up if I ever wanted to balk at a warranty claim? Unless you fill the tank with half diesel, water, or anything other than gasoline...as long as the knock sensor is working, you probably won't catastrophicly damage your engine with the gas you use.
My final words on this matter, to answer the topic of this thread...no it's not a must. It's recommended.
My own personal opinion? I would use premium anyways. You did in fact pay more for the Acura version of the Pilot. One of the differences is more power. You can really only take advantage of that power by using premium (unless the air temps are really cool where you live). Why not take advantage of it? Otherwise...you're complaining about having to a few extra bucks here and there for gas, yet you had no problem paying several thousands more for the Acura tuned engine over the Honda. And that to me is petty.
I'm aware that some of you are technically savvy enthusiats, engineers, or whatever...and your minds can't be changed because no matter what anyone else says, you believe they are wrong since they lack the analytical ability and degrees on the wall you have and they're nuts to doubt you because you've figured it all out. I've gone up against these types before, and it's just hilarious to me that anyone would still doubt what a professional mehanic who knows theory of operation, technical specifications, diagnosis, and repair of their car better than they think they do. So if any of you care to disagree with what I've said, other than the personal opinion in the last paragraph...go ahead and post it. I'll just rebut every post with simply this... :21: |
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| EXCALIBUR |
quote:
Originally posted by SuperTech
My final words on this matter, to answer the topic of this thread...no it's not a must. It's recommended.
That about sums up everything nicely.:4: |
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| anjan |
| I had to respond again because of SuperTech's great reply. I couldn't have it said it better if my life depended on it :) Great job! |
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| DaleB |
Some are very good at making assumptions with no knowledge or references, whether they be from Google or a text book at home.
No one said acura engineers are stupid, etc. But has anyone actually talked to one on the subject at hand?
No one ever suggested running the MDX on anything but pump gasoline, so you folks who find it necessary to exaggerate to make a point, can stop.
Thanks ST for throwing in your automotive expertise in the mixture, and adding clarity to the final blend. :) |
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| DaleB |
quote:
Originally posted by anjan
I couldn't have it said it better if my life depended on it :)
I'm glad it didn't !!
:D
quote:
Originally posted by anjan
For $50 (I know that's unthinkable who are saving $3.00 per tank) will really tell you what extended use of regular fuel has wrought on the pistons and emissions.
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| anjan |
quote:
Originally posted by DaleB
I'm glad it didn't !!
:D
I'm glad too :4: since the same thing said another way by SuperTech tasted so sweet, didn't it? Cut and dry observations are difficult to digest. |
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| Ronsully |
quote:
Originally posted by SuperTech
I doubt there'd be any difference if you drove the same with premium or regular unleaded. The amount of deposits left on the piston, valves, and combustion chamber have much more to do with driving style and quality of gas used. Chevron is arguably the best quality gas out there. Their Techron additive is in my opinion the best one of all the gasolines. And unlike Shell...they put this additve in all three grades. So if you used Chevron, no matter the grade...you'd have less deposts than if you had been tanking up at Arco all this time. Also...someone who is doing full throttle pulls on a regular basis isn't going to have many carbon desposits vs. someone who drives like there's an egg under the throttle. Ever see that initial poof of black smoke from the back of a car when someone gives it the whip? That's carbon built up in the combustion chamber goign bye bye.
I just had to make a comment about this. You are speaking of detergents in gas. I am speaking about octane. Compression test/leak down test will show you if the motor is hurt from detonation among other things. Also, the poof of black smoke may not be carbon build up. If the smoke is blueish it could be oil burning. Black smoke to me could also mean running rich or a burnt valve. |
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| DaleB |
quote:
Originally posted by Ronsully
I just had to make a comment about this. You are speaking of detergents in gas. I am speaking about octane. Compression test/leak down test will show you if the motor is hurt from detonation among other things. Also, the poof of black smoke may not be carbon build up. If the smoke is blueish it could be oil burning. Black smoke to me could also mean running rich or a burnt valve.
I think ST was just adding some info with regards to the small discussion on engine deposits one poster was asking about. It hardly takes away from the crux of the discussion. |
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| JL_SS |
| OK, if everyone is going to agree with Supertech then maybe his response should be posted as a sticky in the FAQ section so that a new premium gas thread is not started every week......... |
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| Ronsully |
quote:
Originally posted by JL_SS
OK, if everyone is going to agree with Supertech then maybe his response should be posted as a sticky in the FAQ section so that a new premium gas thread is not started every week.........
Yes.. very good idea.. |
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| DaleB |
quote:
Originally posted by Ronsully
Yes.. very good idea..
There is general consensus the man with his hand on the wrench has a clear picture of Acura's recommendation.
So now that only leaves about another 2 dozen topics that need stickies....one down.....:cool: |
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| SuperTech |
quote:
Originally posted by Ronsully
I just had to make a comment about this. You are speaking of detergents in gas. I am speaking about octane. Compression test/leak down test will show you if the motor is hurt from detonation among other things. Also, the poof of black smoke may not be carbon build up. If the smoke is blueish it could be oil burning. Black smoke to me could also mean running rich or a burnt valve.
I warned you...
:21: :21: :21:
Everything you need to know was in my last post. You didn't quote it, but here. Let me quote the part that you need to study more.
quote:
Originally posted by SuperTech
as long as the knock sensor is working, you probably won't catastrophicly damage your engine with the gas you use.
Forget compression tests, smoke, or burning oil. The knock sensor is the key here. It allows you to "get away with" any octane you want. If your knock sensor does not work (most common cause for failure, believe it or not, is that the single wire that goes to it under the intake manifold gets chewed by rodents), then the check engine light will be on, the computer will default to a failsafe fuel/timing curve to avoid damage, and you'll be having that taken care of at the dealer in hopefully short time. But...since it DOES work, it will do what it's supposed to and prevent any damage from occuring by detonation.
Now you could theorize that driving like a grandma could build up carbon on the piston, valves, and combustion chamber...enough so that it can effectively raise the compression ratio. Higher compression ratio = more chance of detenation. Assuming you didn't change your driving style, you'd keep building up carbon, and keep needing more octane to avoid pinging and the knock sensor intervening to pull timing back. Eventually, the carbon would build up so much that the compression ratio would be so high, that even Av Gas, and the knock sensor retarding timing to the limit still couldn't avoid detenation and then you have the damage resulting from constant detonation that you keep implying will happen. Sure...it's possible. But this would take a process of several hundred thousand miles (I doubt any of you will keep your MDX that long), and the head gaskets would probably blow from the increased compression long before the computer just absolutely can not retard anymore timing.
In other words, as I said...you will not damage the engine from deviating from the recommended octane fuel. Deposits can clog things or build up in places...and they can cause damage. But the octane itself...that's what the knock sensor is for. Think of it as an "octane detector" if you want. |
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| mgmdx |
A relevant article on testing was done by Car and Driver magazine on Regular vs Premium topic. Although this article was done in Nov 2001, the results are still valid today.
Partial summary from this article reads as follows:
"Cheapskates burning regular in cars designed to run on premium fuel can expect to trim performance by about the same percent they save at the pump. If the car is sufficiently new and sophisticated, it may not suffer any ill effects, but all such skinflints should be ready to switch back to premium at the first sign of knock or other drivability woes."
Read on... and then make your own choice.
http://www.caranddriver.com/article...4&page_number=1
In my case, $3 per tank difference (approximately .15x20gal), which amounts to approximately $144 per year, is cheap insurance that allows my MDX to perform at the peak performance level when needed.
I will be better off making up this $3 per tank weekly difference by reducing my food intake, which is better for my health anyway. :) |
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| EXCALIBUR |
quote:
Originally posted by mgmdx
I will be better off making up this $3 per tank weekly difference by reducing my food intake, which is better for my health anyway. :)
Cheesecake, gasoline, cheesecake, gasoline...decisions, decisions, decisions.;) |
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| nightguy |
| I'll still take the Miller Lite over 91. The X may not run as smoothly but I will. |
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| Sooner in FL |
quote:
Originally posted by mgmdx
A relevant article on testing done by Car and Driver magazine on Regular vs Premium topic. Although this article was done in Nov 2001, the results are still valid today.
Partial summary from this article reads as follows:
"Cheapskates burning regular in cars designed to run on premium fuel can expect to trim performance by about the same percent they save at the pump. If the car is sufficiently new and sophisticated, it may not suffer any ill effects, but all such skinflints should be ready to switch back to premium at the first sign of knock or other drivability woes."
Read on... and then make your own choice.
http://www.caranddriver.com/article...4&page_number=1
In my case, $3 per tank difference (approximately .15x20gal), which amounts to approximately $144 per year, is cheap insurance that allows my MDX to perform at the peak performance level when needed.
I will be better off making up this $3 per tank weekly difference by reducing my food intake, which is better for my health anyway. :)
My point exactly. Spend a little and get some preventative maintance. |
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| frainc |
quote:
Originally posted by nightguy
I'll still take the Miller Lite over 91. The X may not run as smoothly but I will.
:21: |
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| harmonr1 |
quote:
Originally posted by harmonr1
...I get exactly 20.1 mpg and have to fill up every other day. The mpg is surprisingly consistent and I've checked it with the trip computer, actual fill-ups using the odometer, and over several fill-ups. It currently costs about $48 to fill it up with 1/8 of a tank left.
As an experiment, I'm going to use premium (don't know the octane rating here in CA but probably 93) and test my gas mileage. I'll post the results as well as any noticeable power differences going through the mountain pass. A week should be enough as gas topped $3/gal yesterday. Also, I have always used Chevron exclusively so I will be able to rule out any brand differences. I just hope my bank account can stomach the test!
And the results are in...(drum roll please)...After switching to Chevron Premium (91 octane it turns out), the mileage stayed exactly the same at 20.1 mpg. As far as increased performance, it's hard to say. It might have felt a little zippier when passing but it could have been just as much mental (knowing that I have premium gas instead of regular so it should be zippier) as a real sensation. But nontheless, the change in grade had no difference on the mpg. Just my 2 cents. But keep the debaye going...and friendly...as it's been very educational.:4: |
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| gdot |
| After reading this thread, I decided to switch to regular unleaded from premium for a couple of tanks to see what would happen. I can't wait to switch back. The loss of performance sucks and I find myself with the gas pedal on the floor a lot more often to try to compensate. That might explain the decrease of fuel economy from 16.1 to 14.9. I do have 22's, so I'm thinking I need that extra octane to get those wheels going. So, it's back to premium for me. |
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| DaleB |
| I suspect this topic will die when the last MDX is a rusted out hulk and headed for a crusher. :D |
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| msu79gt82 |
quote:
Originally posted by DaleB
I suspect this topic will die when the last MDX is a rusted out hulk and headed for a crusher. :D
Yea but its a known fact that a car crusher running on 93 will compress an MDX to 17.9 inches thick; whereas if you skimp on 87 it'll only compress it down to 18.5 inches :cool: :1: Assuming no pre-detonation of course. |
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| JL_SS |
quote:
Originally posted by msu79gt82
Yea but its a known fact that a car crusher running on 93 will compress an MDX to 17.9 inches thick; whereas if you skimp on 87 it'll only compress it down to 18.5 inches :cool: :1: Assuming no pre-detonation of course.
You forgot to factor in whether the gas is top-tier or not and whether it is running synth or dino.............. :D . |
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| MrPrescott |
quote:
Originally posted by carguy1234
My X is similar to yours - I get routinely 1.5-2MPG better with the 93 Vs the 87. I wonder - do you drive a lot of hills? My main trip (back and forth to work) has a few steep grade hills that I need to climb quickly to merge in with traffic. The 87 tanks don't seem to like to do this, and I think that's where I see the difference.
If I'm on a road trip and lock the cruise control at ~70, I can get 24MPG+ with either 87 or 93. On my "standard trips", I get ~16.7 with the 87 and ~18.4 with the 93. My price difference between the two is only about 14 cents here usually, so I'll stay with the 93.
But what about the EGR valve contamination? My experience is same mileage - and if it saves me having to pay $150 to clean the EGR valve, it's a no-brainer. |
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| nightguy |
quote:
Originally posted by MrPrescott
But what about the EGR valve contamination? My experience is same mileage - and if it saves me having to pay $150 to clean the EGR valve, it's a no-brainer.
:confused: |
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| SuperTech |
quote:
Originally posted by MrPrescott
But what about the EGR valve contamination? My experience is same mileage - and if it saves me having to pay $150 to clean the EGR valve, it's a no-brainer.
Worried about deposits? Read this again.
quote:
Originally posted by SuperTech
The amount of deposits left on the piston, valves, and combustion chamber have much more to do with driving style and quality of gas used. Chevron is arguably the best quality gas out there. Their Techron additive is in my opinion the best one of all the gasolines. And unlike Shell...they put this additve in all three grades. So if you used Chevron, no matter the grade...you'd have less deposts than if you had been tanking up at Arco all this time. Also...someone who is doing full throttle pulls on a regular basis isn't going to have many carbon desposits vs. someone who drives like there's an egg under the throttle. Ever see that initial poof of black smoke from the back of a car when someone gives it the whip? That's carbon built up in the combustion chamber goign bye bye.
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| QRTLOW |
Orginally posted by GDOT
"That might explain the decrease of fuel economy from 16.1 to 14.9. I do have 22's, so I'm thinking I need that extra octane to get those wheels going"
I'm thinking of 22" now. I see you can do a P265/45/22 and it clears the struts and looks taller. I wonder if I can stretch it to P275 for a wider footprint?? Any ideas??
Also, the wheel diameter increase is an added demand on braking and turning bigger wheels taxes the engine and fuel demand.
Qrtlow
04 Touring
Black on Black |
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| Mahereb |
:4: Last week I tried the regular gas and I would never do it again.
The performance of my MDX was not the same and I got lower gas millage than what I get with the premium.
It is not worse trying it. Just stick to the manufacture recommendation. If you can not, then I recommend to use about 50/50 mix of regular and premium, thus you will get the 91 octane recommended by the manufacture! |
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| Sly_ |
I always use 94 octane that is available at my local Petro Canada. They also have 91 and 89.
Is using 94 octane overkill? :confused: |
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| DaleB |
quote:
Originally posted by Sly_
I always use 94 octane that is available at my local Petro Canada. They also have 91 and 89.
Is using 94 octane overkill? :confused:
I think so. If the manufacturer designs the engine to work most efficiently at a recommended octane, I doubt if they are going to offer you more power if you use something higher.
Maybe a Corvette or other high performance sports car may have additional margin for cranking out even more power with more ocatne. But most cars that could do that are not on the road anymore, unless they were restored, and run over 11:1 compression ratios and hope they will always find fuel for it, so it does not sound like somebody dropped marbles in the intake.
I just don't believe going over 91 will give you any benefit for the majority of today's production cars. And if it does, I doubt it's enough to notice except as less change in your pocket.
Maybe a dyno out there will prove me wrong. :) |
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| wilkie1683 |
| i am very sorry .. this is a very stupid question but i just have to ask .. what does PING means??? ... |
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| dj-mdx2 |
As far as I understand, pinging sounds like rocks being thrown around inside your engine.
"The hotter your engine is, the more likely your engine is to ping. The farther your timing is advanced, the more likely your engine is to ping. The higher your compression ratio is, the more likely your engine is to ping. The lower the octane of gas you use, the more likely your engine is to ping. " |
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| wilkie1683 |
| thank you ... I live in LA .. maybe I should put the 97 gas in for the first 6 month just so that I FEEL better ... and down grade later... |
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| SuperTech |
| 97? Wow. I didn't know you needed near race quality gas to slog along in traffic over there. |
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| mp3car |
quote:
Originally posted by wilkie1683
i am very sorry .. this is a very stupid question but i just have to ask .. what does PING means??? ...
It's what someone says before PONG ;) |
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| nightguy |
I just switched gas stations and wow, what a difference ! My Taurus was lucky to get 24 mpg and every other week was stumbling so badly the check engine light would come on steady for a few days. I was ready to replace my O2 sensor.
By the second tank of the new gas, no more check engine light and I'm averaging 28 mpg (sometimes more)...which is what the sticker said for highway driving. And of course I'm just running 87. I think the other place loads up with extra ethanol.
No change in the MDX yet but I finally put in the new air filter I ordered months ago. I was waiting for some major construction to be completed first. |
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| socalJD |
quote:
Originally posted by nightguy
I just switched gas stations and wow, what a difference. . .
So, which stations did you swith from & to ???? :1pat: |
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| Smiling Phases |
Hi everyone. First post for me. First MDX for me. I am going to be flying to Dallas to pickup a 2001 MDX, hence my first Acura product. Reading with interest the postings re gasoline. I will give you the best/most definitive evaluation on this touchy subject. I will be driving it home, 2,000 miles, over 3 days through mountains, plains, heat, cold (hopefully no snow!).
I will put in 3 tanks of premium, and carefully log the details/results. Then 3 tanks of mid grade and following that, 3 tanks of regular gas. That way with 3 tanks, there will be no 'contamination' and it will allow enough of each gas to go thru the engine. This one has 91k miles on it so it's well broke in. I don't know what to expect as an owner but most people are positive and I hear the engine is pretty good. Having sold a 1995 Jeep Grand Cherokee with the 5.2L V8, anything is an improvement from that piece of junk.
Feel free to email me any suggestions or help you can recommend including about the upcoming timing belt replacement I hear is required around 100k miles. And yes, I am saving many thousands of dollars compared to here, plus no rust, rock chips and other such damage that we get here. Needless to say I could buy all the MDX's possible and sell them here for a very tidy profit, and could include profit for you. Thank you. |
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| DaleB |
quote:
Originally posted by Smiling Phases
Hi everyone. First post for me. First MDX for me. I am going to be flying to Dallas to pickup a 2001 MDX, hence my first Acura product. Reading with interest the postings re gasoline. I will give you the best/most definitive evaluation on this touchy subject. I will be driving it home, 2,000 miles, over 3 days through mountains, plains, heat, cold (hopefully no snow!).
I will put in 3 tanks of premium, and carefully log the details/results. Then 3 tanks of mid grade and following that, 3 tanks of regular gas. That way with 3 tanks, there will be no 'contamination' and it will allow enough of each gas to go thru the engine. This one has 91k miles on it so it's well broke in. I don't know what to expect as an owner but most people are positive and I hear the engine is pretty good. Having sold a 1995 Jeep Grand Cherokee with the 5.2L V8, anything is an improvement from that piece of junk.
Feel free to email me any suggestions or help you can recommend including about the upcoming timing belt replacement I hear is required around 100k miles. And yes, I am saving many thousands of dollars compared to here, plus no rust, rock chips and other such damage that we get here. Needless to say I could buy all the MDX's possible and sell them here for a very tidy profit, and could include profit for you. Thank you.
Be very interested in your experiences. I doubt you will get any meaningful mileage comparisons with different fuels, since you will not be taking the same road every time. But how you feel it runs should be helpful.
Be careful you don't let the tank run too low just to get repeatable results. Not a good idea for more than one reason.
Personally, I would not run under the worst conditions with regular fuel, esp. over mountain passes, etc.
But that's your call and I'm sure many have no problem with it.
(I run 89 almost exclusively).
I would plan on getting the belt changed soon after you get back, along with the water pump (to avoid a bigger bill to replace it later if it goes bad) and of course the spark plugs.
Have a great trip! If the vehicle has been well maintained, you should enjoy the ride! |
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| msu79gt82 |
quote:
Originally posted by Smiling Phases
Hi everyone. First post for me. First MDX for me. I am going to be flying to Dallas to pickup a 2001 MDX, hence my first Acura product. Reading with interest the postings re gasoline. I will give you the best/most definitive evaluation on this touchy subject. I will be driving it home, 2,000 miles, over 3 days through mountains, plains, heat, cold (hopefully no snow!).
I will put in 3 tanks of premium, and carefully log the details/results. Then 3 tanks of mid grade and following that, 3 tanks of regular gas. That way with 3 tanks, there will be no 'contamination' and it will allow enough of each gas to go thru the engine.
First welcome to the group and good luck with your MDX :1:
I do not mean to sound disrespectful, but your proposed "test" will absolutely NOT be definitive. To be a definitive scientific test you would need to drive each grade of gas over the EXACT same course under the EXACT same conditions. |
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| SuperTech |
| The octane number for premium varies by state. In CA, it's 91. Other parts of the country, it's 92 an maybe even 93. |
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| screbr |
Nice to see a fellow Yellow Jacket on this board! How bout that big win over Duke this weekend!!!
Is the "MSU" for Michigan State? |
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| msu79gt82 |
quote:
Originally posted by screbr
Nice to see a fellow Yellow Jacket on this board! How bout that big win over Duke this weekend!!!
Is the "MSU" for Michigan State?
Go Jackets :cool: :1:
Nope - Memphis Tigers. |
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| Pierre |
quote:
Originally posted by wilkie1683
thank you ... I live in LA .. maybe I should put the 97 gas in for the first 6 month just so that I FEEL better ... and down grade later...
Wow -- that's almost aviation gas territory (100 octane). You do not need that much octane. You're just throwing money away. Use what the manual tells you. I've owned many cars in my life and have been very careful to follow what the manual says. The guys (and gals) who build these things know what they're doing. Why should I second-guess them? |
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| carguy1234 |
I'm still fickle about the octane to use....
I've ruled out the 87, since I can make my MDX ping slightly when under heavy load (most probably couldn't hear this, but my ears are super sensitive to this kind of thing). I can also detect a MPG difference between 87 and anything 90 and above (honest - I've set up DOE's with managed variables, and I get statistically significant lower MPG with the 87 (via paried-t analysis)).
So my quandary is between 90 and 92. I can't really notice much difference between the two, so I was planning an staying with the 90. But then a coworker told me to stay away from the mid-grades, since people don't use it as much, so the quality (i.e. freshness) is worse. So I wonder, is this pure bunk, or does anybody else recommend staying away from the mid grade.
I get my gas at Holiday (the blue planet stuff) since the hybrid drivers around here swear by it for it's 'greenness'. Possibly also bunk, but those stations are my closest and cheapest too. They are priced currently as follows: |
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| DaleB |
quote:
Originally posted by carguy1234
I'm still fickle about the octane to use....
I've ruled out the 87, since I can make my MDX ping slightly when under heavy load (most probably couldn't hear this, but my ears are super sensitive to this kind of thing). I can also detect a MPG difference between 87 and anything 90 and above (honest - I've set up DOE's with managed variables, and I get statistically significant lower MPG with the 87 (via paried-t analysis)).
So my quandary is between 90 and 92. I can't really notice much difference between the two, so I was planning an staying with the 90. But then a coworker told me to stay away from the mid-grades, since people don't use it as much, so the quality (i.e. freshness) is worse. So I wonder, is this pure bunk, or does anybody else recommend staying away from the mid grade.
I get my gas at Holiday (the blue planet stuff) since the hybrid drivers around here swear by it for it's 'greenness'. Possibly also bunk, but those stations are my closest and cheapest too. They are priced currently as follows:
I recently read in the auto section of the paper, one of the 'car guys' (not ClickNClack) said it's best to burn the fuel recommended by the manufacturer.
That while the computer will allow adjustment to lower octane fuels, they burn cooler (as in less efficient) and there is greater opportunity for carbon build-up over time. He said the recommendation is primarily based on compression ratio.
Of course, this does not completely explain the recommendation of Regular for the Honda Pilot. | | | | | |
