Those with 2.3L engines, which octane gas do you put in?

amiro

Member
We've got 87, 89, 92, and 94 octane here. The manual says 87 is needed, is that enough? i generally like to put in one grade higher in my cars.
 
dont bother. if the manual says 87 no reason to upgrade unless you start running something like n2o or turbo or s/c
 
Higher octane levels should be used in high performance cars and cars with high compression ratios. However, once you start to hear you engine knocking or pinging, that's when you should step up one grade of octane.

That's probably how this "old wives tale" got started, higher octane levels in your gas tank will result in high levels of performance.
 
I have noticed a little diffrence with sheels V-Power 94 octane gas, it might just be me, I like to hear from some one else who tired it
 
you shouldnt use octane higher than what the manual says. This engine has been calibrated to work most efficiently with 87 octane.
 
only the 2.3 jdm mazda 3 and 6 is required to use 91 octane. our pcm will only detect a change if you go below 87 octane and retard timming. 91 will not completely burn and cause build up for our us/canada spec cars uless you "touched" your ignition system, added turbo/super or spraying...
 
amiro said:
We've got 87, 89, 92, and 94 octane here. The manual says 87 is needed, is that enough? i generally like to put in one grade higher in my cars.

This is going to sound odd but me and the guys at dyno4mance, GA had a theory asking if it is better to use a mid grade gasoline over bottom grade. Well research and dyno testing gave proof that useing a mid grade gasoline did infact save money and result in a better a/f rateing and better gas milage. The theory is simple really with cars today ecu learn to adapt to the way we drive and the conditions in which it is used. This brought up the question if the car was used to a richer condition would the ecu compensate for that.... Time for test subjects, Andrew of dyno4mance wife drives a honda van and his monther in law drive the same year honda van (both same model and specs) his wife has always filed up with mid grade gasonline where his mother in law used the "cheap stuff". Well they strapped the two vans down and did base line testing (lol dyno tuned the cars lol) In the end both vans came out with the "same" whp but the intresting part were the a/f curve and slightly more torque from better gas milage. The mid grade van had a much better a/f reading than the "cheap" stuff van. This resulting in less wasted gas.
Now looking at the better gas milage and calculating amout of fills in a month or year even it was easy to see that yes at the gas station you pay 10 cents more but you stop less and get better gas milage. (forgive me I forget the total saveings but it was quite a bit in just a months time) For proof Andrew has a video of the van being dyno'd at Dyno4mance and you can always call and asking about how it was proven that mid grade gasoline gave better gas milage and saves money in the end.

www.dyno4mance.com


anyways my .02, also sorry for the poor writing its late and kinnda tired but if you have question feel free to message me or contact andrew at dyno4mance the only tuneing shop I will use for my toys (cool)
 
not to say anthing that might sound stupid(like most stuff I say doesn't) Honda engines and pcms are difrent from mazda and other cars I experienced...higher an octane the more I lost out...when I drained the tank and went back 87 it felt like I gaind HP off a but dyno. If you wish to use 89 and up in vehices other than the EVO then I can't phiscally be there at the pump lexuring you.
 
While your lil' experiment sounds like a good idea, it seems far from controlled. Did the cars have the same air filters? were they both equally clean, allowing the same air flow through? Were o2 sensors both operating in the same manner? There are hundreds of different factors that could have varied between two cars. I don't quite think the experiment is very relevant.

Additionally, can you really get torque from better gas mileage? Seems like a really whack claim to make.

DigitalHeadShot said:
This is going to sound odd but me and the guys at dyno4mance, GA had a theory asking if it is better to use a mid grade gasoline over bottom grade. Well research and dyno testing gave proof that useing a mid grade gasoline did infact save money and result in a better a/f rateing and better gas milage. The theory is simple really with cars today ecu learn to adapt to the way we drive and the conditions in which it is used. This brought up the question if the car was used to a richer condition would the ecu compensate for that.... Time for test subjects, Andrew of dyno4mance wife drives a honda van and his monther in law drive the same year honda van (both same model and specs) his wife has always filed up with mid grade gasonline where his mother in law used the "cheap stuff". Well they strapped the two vans down and did base line testing (lol dyno tuned the cars lol) In the end both vans came out with the "same" whp but the intresting part were the a/f curve and slightly more torque from better gas milage. The mid grade van had a much better a/f reading than the "cheap" stuff van. This resulting in less wasted gas.
Now looking at the better gas milage and calculating amout of fills in a month or year even it was easy to see that yes at the gas station you pay 10 cents more but you stop less and get better gas milage. (forgive me I forget the total saveings but it was quite a bit in just a months time) For proof Andrew has a video of the van being dyno'd at Dyno4mance and you can always call and asking about how it was proven that mid grade gasoline gave better gas milage and saves money in the end.

www.dyno4mance.com


anyways my .02, also sorry for the poor writing its late and kinnda tired but if you have question feel free to message me or contact andrew at dyno4mance the only tuneing shop I will use for my toys (cool)
 
do be accurate you'd have to test them when they were exactly the same then test them using the diffrent gasoline, i mean take two cars coming off the assembly line and their likely to run a bit off.
 
yeah thats the reason why we say dyno car bone stoch and then dyno after mods.
 
DigitalHeadShot said:
This is going to sound odd but me and the guys at dyno4mance, GA had a theory asking if it is better to use a mid grade gasoline over bottom grade. Well research and dyno testing gave proof that useing a mid grade gasoline did infact save money and result in a better a/f rateing and better gas milage. The theory is simple really with cars today ecu learn to adapt to the way we drive and the conditions in which it is used. This brought up the question if the car was used to a richer condition would the ecu compensate for that.... Time for test subjects, Andrew of dyno4mance wife drives a honda van and his monther in law drive the same year honda van (both same model and specs) his wife has always filed up with mid grade gasonline where his mother in law used the "cheap stuff". Well they strapped the two vans down and did base line testing (lol dyno tuned the cars lol) In the end both vans came out with the "same" whp but the intresting part were the a/f curve and slightly more torque from better gas milage. The mid grade van had a much better a/f reading than the "cheap" stuff van. This resulting in less wasted gas.
Now looking at the better gas milage and calculating amout of fills in a month or year even it was easy to see that yes at the gas station you pay 10 cents more but you stop less and get better gas milage. (forgive me I forget the total saveings but it was quite a bit in just a months time) For proof Andrew has a video of the van being dyno'd at Dyno4mance and you can always call and asking about how it was proven that mid grade gasoline gave better gas milage and saves money in the end.

www.dyno4mance.com


anyways my .02, also sorry for the poor writing its late and kinnda tired but if you have question feel free to message me or contact andrew at dyno4mance the only tuneing shop I will use for my toys (cool)
Hi there
I have just read your post and there are a few things to correct....
The savings over the lifetime of the van that run the higher octane fuel were calculated at over $300.00...(over three years)
Both filters were changed for new..
More torque was actually displayed lower down the rpm on the van running the richer fuel map, this is quite normal and we see this happen all the time when mapping various cars.
All that was happening was the ECU on the Van running the better gas had selected a fuel trim that optimized the vans performance, reliability and drivability...this happened to be a full 1.5 points in A/F above 40% TP than the van that run the 87 octane gas..
To conclude the test a tank of 93 oct was put through the van over the next week and the van was re dynoed with the same grade fuel in as the first van, the results of that final test showed that once the fuel was changed to a higher octane this vans ECU had selected the exact same map as the first van we dynoed a week previously.
It is not uncommon for some ECU's that are reset on the dyno to display a very rich condition on the very next pull....this is done naturally on purpose to allow the ECU to collect data before selecting the relevant fuel map.
Todays modern ECU's have multiple fuel maps/trims programmed into them. we have observed many times different fuel trims being used on the same make model year vehicle depending on a number of factors....if you think about it this is logical as the same vehicle is sold into different markets...for example California with 91 octane, the south west with thier oxygenated fuel and colorado where the altitude exceeds 9-10,000 ft above sea level an so on
by making multiple fuel/timing maps available to the ECU the performance and reliability remains safe and constant no matter where it is sold in North America.
If I get time later I will post both graphs...
Hope this helps your debate...
regards
Andrew
Dyno4mance.com
 
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3 and 6 can't change fuel maps w/o modifications...87 and below is all it can detect. Godamn shell and their V-power brainwashing ads!
 
our cars can't detect anything over 87. Everyone is under the beleif going above 87 is better for their car cause 87 is "The Cheap Stuff" 91 isn't doing anything but clogging injectors, cat, and washing down cylinders untill you can burn hotter or change timing. When vvt kicks in 91 still will not work. I said shell cause they basicly in every damn ad that you should pump 93 cause thats the grade with all the detergents and goodes for your car and extend its life. If I told you this cigarrete will not kill you faster but for $.20 more than the brand you smoke now will you switch brands?
 
Da 6 said:
our cars can't detect anything over 87. Everyone is under the beleif going above 87 is better for their car cause 87 is "The Cheap Stuff" 91 isn't doing anything but clogging injectors, cat, and washing down cylinders untill you can burn hotter or change timing. When vvt kicks in 91 still will not work. I said shell cause they basicly in every damn ad that you should pump 93 cause thats the grade with all the detergents and goodes for your car and extend its life. If I told you this cigarrete will not kill you faster but for $.20 more than the brand you smoke now will you switch brands?
Your theory of how your car operates is flawed at so many levels it would be difficult as well as time consuming for me to respond further.
Your car will be fine if you continue to use inexpensive 87 octane fuel
Have a great Christmas and a happy new year (drive)
 
? n/m I used 87 in engine #1 and now engine#2 those views were an example...not of my own...

P.S. Happy Holidays to you too(birthday)
 
I have actually thought about putting 89 in mine. I hear a little spark knock/pinging usually under easy accelration in 3rd and 4th gears. It isn't that I am in the wrong gear, because the car is still accelerating fairly easy. I dunno.... thoughts?
 

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