Honestly has anyone noticed a difference while driving on regular and premium?
#1
Honestly has anyone noticed a difference while driving on regular and premium?
The manual says a slight decrease in "Performance" but have u guys really noticed anything like horse power difference etc.
#6
I've talked to a mazda mechanic and he said that premium contains lead which in the long term clogs and damages the engine, once again u may not feel a difference in the short run but in the long term the lead will damage the engine.
#8
Administrator
iTrader: (7)
56,000 + miles of 91 octane. Never seen a drop of 89, wouldn't know...
#9
Certified Mazda Tech
*removed due to improper word choice*
*intentions are better clarified then this post further down.*
kevin.
*intentions are better clarified then this post further down.*
kevin.
Last edited by teknics; 04-16-2009 at 08:32 PM.
#10
Certified Mazda Tech
nope, the ignition timing maps are *designed* for premium octane, california emissions vehicles are tuned for 91 octane. While the PCM will adjust the map based on knock sensor data and other inputs you want to keep everything as close to what the PCM expects/wants as possible.
true, 89 octane *probably* wont hurt, but thats because the motor isn't designed to have the octane as it's only lifeline. a change in octane on a highly modified, built to the borderline of safety and tuned on 93 octane can blow from one run on 89.
lead in street gas is illegal and would destroy your cat, the tech you spoke with is wrong. Otherwise lead is actually a lubricant and wouldnt clog or do any other damage to the motor's internals. The only time you'll find lead in fuel is higher octane, non-street gas. Such as in cam2's 105 octane leaded fuel.
If you have a midpipe you can run leaded gas with few if any problems, but premium fuel contains *no* lead, or it wouldnt be legal for sale in the US for use in a street vehicle)
cause your car wasn't tuned to the 91, it was tuned to the 93, therefore your timing was off.
tune it to 91 and you'll achieve the same results if not *better* due to the faster burning and advanced timing required.
personal opinion, you own a $30k+ *sports* car if you cant afford the gas it requires sell it since that is going to be the least of your worries down the road. If you *have* to use standard octane look into an auxiliary injection system to add a layer of safety against pre-ignition/detonation.
kevin.
true, 89 octane *probably* wont hurt, but thats because the motor isn't designed to have the octane as it's only lifeline. a change in octane on a highly modified, built to the borderline of safety and tuned on 93 octane can blow from one run on 89.
If you have a midpipe you can run leaded gas with few if any problems, but premium fuel contains *no* lead, or it wouldnt be legal for sale in the US for use in a street vehicle)
tune it to 91 and you'll achieve the same results if not *better* due to the faster burning and advanced timing required.
personal opinion, you own a $30k+ *sports* car if you cant afford the gas it requires sell it since that is going to be the least of your worries down the road. If you *have* to use standard octane look into an auxiliary injection system to add a layer of safety against pre-ignition/detonation.
kevin.
Last edited by teknics; 04-16-2009 at 07:35 PM.
#11
Out of NYC
iTrader: (1)
Race gas, some yes.
Lead is a wonderful lubricant, try to get a piece of paper, and rub your pencil on it. Then feel the paper, nice and smooth ,right ? (yeah I know some pencils are made from graphite, but lead is still wonderful)
its just that Lead is not that wonderful for human beings.
Last edited by nycgps; 04-16-2009 at 07:39 PM.
#12
Administrator
i've had knock on 87 but none on 89 and of course never on 90-whatever
kevin thanks for getting that lead bit so i dont have to buuuuuuttt...
you are wrong about lower octane fuels having a higher burn rate than higher octane fuels. the octane tells you zip about the burn rate. you can look up previous discussions for the info i and others have posted before or i can post it here later when i have time.
kevin thanks for getting that lead bit so i dont have to buuuuuuttt...
you are wrong about lower octane fuels having a higher burn rate than higher octane fuels. the octane tells you zip about the burn rate. you can look up previous discussions for the info i and others have posted before or i can post it here later when i have time.
#13
Certified Mazda Tech
i've had knock on 87 but none on 89 and of course never on 90-whatever
kevin thanks for getting that lead bit so i dont have to buuuuuuttt...
you are wrong about lower octane fuels having a higher burn rate than higher octane fuels. the octane tells you zip about the burn rate. you can look up previous discussions for the info i and others have posted before or i can post it here later when i have time.
kevin thanks for getting that lead bit so i dont have to buuuuuuttt...
you are wrong about lower octane fuels having a higher burn rate than higher octane fuels. the octane tells you zip about the burn rate. you can look up previous discussions for the info i and others have posted before or i can post it here later when i have time.
"If we just look at the fuel to reduce the engine's tendency to detonate, we have to look at the chemistry of the fuel itself. This can be accomplished in several ways, as we can alter the chemistry of the fuel by adding octane or several other chemical compounds. Yes, octane is a chemical, just like benzene, tetraethyl lead, and isooctane. The formula for octane is CH3 (CH2)6CH3. From a molecular level, octane is a chain of 8 carbon atoms surrounded by 18 hydrogen atoms. It is a measure of the resistance of fuel (in this case gasoline) to knock or pre-ignite. The desired result of combustion is an even, controlled burn of the fuel in the combustion chamber. We want to avoid multiple areas of burn at different rates across the face or crown of the piston."
octane (ŏk'tān') Pronunciation Key
Any of several hydrocarbons having eight carbon atoms connected by single bonds. It is commonly added to gasoline to prevent knocking from uneven burning of fuel in internal-combustion engines.
Any of several hydrocarbons having eight carbon atoms connected by single bonds. It is commonly added to gasoline to prevent knocking from uneven burning of fuel in internal-combustion engines.
I will attempt to no longer use simplified terminology here, or when i do use simplified terminology I will amend it with a "*" and provide a full footnote as to it's specific meaning. I was unaware of the scientific level of speech used here apparently, my bad (do i define this now?)
seriously i'm tired of my *words* being jumped on, at least have a level to stand on, i'm sorry some of us do too much in one day to be able to sit squarely at the computer and completely think out every single thing we type. As we speak I'm building a motor actually, so again my bad* if my wording suffers, what are you doing while on the forum?
hell lets throw in another quote thats almost identical to my original post:
Q. What is Octane?
A. Quite simply, octane is a fuel’s resistance to burn. The higher the octane, the easier it can withstand higher compression and temperature without igniting and causing pre-ignition or detonation.
A. Quite simply, octane is a fuel’s resistance to burn. The higher the octane, the easier it can withstand higher compression and temperature without igniting and causing pre-ignition or detonation.
now if we want to be super technical in reality unless you know your fuel's specific antiknock index, represented in the formula (R+M/2) (R=RON,M=MON). But this is a casual forum...i thought.
kevin.
*my bad - slang used to admit, in 1st person, the failure to accomplish, complete, or do something.
Ex. "i forgot to do the laundry, my bad"
apologies for aggressiveness but seriously this week alone i have had 5 posts taken apart due to simple phrases being misinterpreted. If you need a definition or better explanation of one of my posts or even a specific word my PM box is WIDE OPEN and monitored constantly by my iphone, no need to waste a post (i believe this is even part of the forum rules?), i mean i expect this from typical forum members but.... I do understand that you assumed i was using the industry standard terminological definition of "burn rate" however I was simply using it as basically my own personal abbreviation, in a sense, you should've just PMed me and it would've been easier.
Last edited by teknics; 04-16-2009 at 08:31 PM.
#14
Registered
iTrader: (2)
Premium usually has more cleaning additives - correct? If so, it seems like that makes it worthwhile right there, particularly on our motors.
Also, one issue I became "sensitized" to a few years ago is that no all gasoline is created equal, from a cleanliness standpoint. In fact, my home state, Oregon, is purposely shipped some of the dirtiest gas in the nation. Why? Because we have some of the cleanest air in the nation, so we can "afford" the crappy gas & it's associated increased emmisions.
For that reason alone, I tend to buy premium, with the (perhaps) hope that it is cleaner than regular. Again, if for no other reason, the additives would hopefully help combat the dirty gas.
Don't know if the additives present in premium actually do anything, or if it's marketing crap. Anybody know?
Also, one issue I became "sensitized" to a few years ago is that no all gasoline is created equal, from a cleanliness standpoint. In fact, my home state, Oregon, is purposely shipped some of the dirtiest gas in the nation. Why? Because we have some of the cleanest air in the nation, so we can "afford" the crappy gas & it's associated increased emmisions.
For that reason alone, I tend to buy premium, with the (perhaps) hope that it is cleaner than regular. Again, if for no other reason, the additives would hopefully help combat the dirty gas.
Don't know if the additives present in premium actually do anything, or if it's marketing crap. Anybody know?
#15
Certified Mazda Tech
i'd say each probably has a specific benefit but its hard to choose which is better in overall terms.
kevin.
*special mix - used in place of "proprietary scientific/chemical combination of additional chemicals or additives to the fuel based on results determined in their own personal labs"
#16
Administrator
sorry you took that so badly. it was supposed to be more of a light hearted jab thats why the long buuuuutttttt. judging from your other posts i was surprised to see you make that error. its a pet peeve of mine to not let the octane misinformation go because i have spent so much time previously trying to correct people spreading around the incorrect info.
side note- when i posted that i was
unpacking groceries
feeding a 10 month old
starting dinner
helping my 4 year old pick up his stuff
taking out the recyclables
so yeah some of have more to do than sit at the computer
side note- when i posted that i was
unpacking groceries
feeding a 10 month old
starting dinner
helping my 4 year old pick up his stuff
taking out the recyclables
so yeah some of have more to do than sit at the computer
#17
Certified Mazda Tech
sorry you took that so badly. it was supposed to be more of a light hearted jab thats why the long buuuuutttttt. judging from your other posts i was surprised to see you make that error. its a pet peeve of mine to not let the octane misinformation go because i have spent so much time previously trying to correct people spreading around the incorrect info.
side note- when i posted that i was
unpacking groceries
feeding a 10 month old
starting dinner
helping my 4 year old pick up his stuff
taking out the recyclables
so yeah some of have more to do than sit at the computer
side note- when i posted that i was
unpacking groceries
feeding a 10 month old
starting dinner
helping my 4 year old pick up his stuff
taking out the recyclables
so yeah some of have more to do than sit at the computer
I just dont understand why unnamed people have decided to attack me, so ive been on the defensive lately. nothing like having other people ruin the party huh?
BTW, you win, just *having* a kid eliminates any ability of full focus on anything....ever. lol.
kevin. (not an angry or rude person, don't run away anybody, ask those who've met me I'm relatively reserved and a heavy thinker.)
#19
Registered
iTrader: (4)
More about Lead. Lead was used to increase the octane of gasoline. A byproduct was that it protected/lubricated the valve seats. Lead also leaves deposits. This was bad enough with the spark plugs in the old days. It would turn into Lead fouling between the electrode and ground. Plugs would, at the most last 20k miles. Today, on the piston engines, they last 100K. It would be even worse on the spinning rotors, seals and rotor housings on our engines.
#20
Registered
iTrader: (4)
debatable. Every fuel manufacturer adds its own "special mix"* nevermind government rules and regulations requiring certain amounts of specific "ingredients".
i'd say each probably has a specific benefit but its hard to choose which is better in overall terms.
kevin.
*special mix - used in place of "proprietary scientific/chemical combination of additional chemicals or additives to the fuel based on results determined in their own personal labs"
i'd say each probably has a specific benefit but its hard to choose which is better in overall terms.
kevin.
*special mix - used in place of "proprietary scientific/chemical combination of additional chemicals or additives to the fuel based on results determined in their own personal labs"
#21
Senior Member
Join Date: Jul 2003
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57k on 87 octane Shell. I don't drive the hell out of my car either, so I don't hear marbles in the can. When I first got it, I tried 87 octane after reading the manual and could not tell the difference between regular and premium. I also read early on that may RX7 owners had used 87 octane successfully. I'll post when I need a new engine .
Last edited by rx8cited; 04-16-2009 at 09:47 PM.
#22
Super Moderator
apologies for aggressiveness but seriously this week alone i have had 5 posts taken apart due to simple phrases being misinterpreted. If you need a definition or better explanation of one of my posts or even a specific word my PM box is WIDE OPEN and monitored constantly by my iphone, no need to waste a post (i believe this is even part of the forum rules?), i mean i expect this from typical forum members but.... I do understand that you assumed i was using the industry standard terminological definition of "burn rate" however I was simply using it as basically my own personal abbreviation, in a sense, you should've just PMed me and it would've been easier.
Seriously, don't let it get you down and PLEASE DO NOT Let it stop you from forwarding your knowledge and Experience here...OK Kevin.
You will always get accused of talking too much or not enough information, or can you "back up what you say" comments...
While NONE of us are Always correct (some think they are), I like to think in most cases you, I, and a few others (regulars) post what is true as they see it.
Take it easy mate...
Ash
#23
Super Moderator
OH, BTW, I remember back in the 70's before "Unleaded Fuels" Mazda rotaries HAD to run on "Standard" gas, low Octane and low lead, it was a NO NO to put in High lead or "Super" fuels. You were told that "No" performance gains in using Super gas, the Cheaper Low Lead fuels were a marketing advantage for the rotary back then.
#24
Certified Mazda Tech
More about Lead. Lead was used to increase the octane of gasoline. A byproduct was that it protected/lubricated the valve seats. Lead also leaves deposits. This was bad enough with the spark plugs in the old days. It would turn into Lead fouling between the electrode and ground. Plugs would, at the most last 20k miles. Today, on the piston engines, they last 100K. It would be even worse on the spinning rotors, seals and rotor housings on our engines.
kevin.
#25
Registered User
Wow, this is more information than I thought I'd find randomly searching a forum. Thank you.
I have one question though. Isn't it possible for companies to just say that they are giving you high octane gas yet are truly giving you crap without letting you know? How can you separate the lies from the true without the proper knowledge of the intricacies of each company and whatnot?
Forum/Car Noob,
Ace
I have one question though. Isn't it possible for companies to just say that they are giving you high octane gas yet are truly giving you crap without letting you know? How can you separate the lies from the true without the proper knowledge of the intricacies of each company and whatnot?
Forum/Car Noob,
Ace