91 Oct Loss of Power
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From: OC
Originally posted by DB8GSR
The Evo sure is hurting on 91 octane pump gas when it comes to engine performance. Everytime I nail the gas all the way thru redline on the highway is a bit dissapointing. The facial expression look on my face changes from excitement to disappointment.
I have a 5 gallon 100 unleaded octane gas sitting at home and just the other day, i decided to pour 2 gallons into the tank. Once the mixture settles into the tank, I drove the car again and you can tell a difference from a 3rd gear and 4th gear pulls on the highway. I'm so accustomed to driving high revving honda motors and I like going to redline every now and then and the Evo on the other hand will love you more if you put higher better gas into.
The Evo sure is hurting on 91 octane pump gas when it comes to engine performance. Everytime I nail the gas all the way thru redline on the highway is a bit dissapointing. The facial expression look on my face changes from excitement to disappointment.
I have a 5 gallon 100 unleaded octane gas sitting at home and just the other day, i decided to pour 2 gallons into the tank. Once the mixture settles into the tank, I drove the car again and you can tell a difference from a 3rd gear and 4th gear pulls on the highway. I'm so accustomed to driving high revving honda motors and I like going to redline every now and then and the Evo on the other hand will love you more if you put higher better gas into.I'm also wondering how soon the change would kick in. I've seen some people quote 100 miles, before the ECU would readjust. So first time I mixed the gas I just waited for the change to take effect. Second time I disconnected the battery for a couple of minutes in the hope it would "reset" itself with regard to how much knock it was getting. And they both felt about the same.
All of the above is real subjective, and of course the real test would be on a dyno, or timed on the track I suppose.
Anybody have any idea as to how soon they think the Evo's ECU would "learn" the new Octane value of the gas it is using ???
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For what it's worth...
Just for fun, I called Mitsubishi and asked them if they stand by their performance numbers on 91 octane.
The lady was perplexed and didn't know how to answer. She looked for the minimum octane rating in her materials, but it wasn't listed (which sounds strange, or suspicious depending on how you look at it).
So she called the engineering department.
The conclusion was, yes, the typical Evo outputs 271 HP on 91 octane gas. Of course, she added that since it was a mass produced car, each one might be different...
Sounds like that's what Shiv is seeing...
Just for fun, I called Mitsubishi and asked them if they stand by their performance numbers on 91 octane.
The lady was perplexed and didn't know how to answer. She looked for the minimum octane rating in her materials, but it wasn't listed (which sounds strange, or suspicious depending on how you look at it).
So she called the engineering department.
The conclusion was, yes, the typical Evo outputs 271 HP on 91 octane gas. Of course, she added that since it was a mass produced car, each one might be different...
Sounds like that's what Shiv is seeing...
Originally posted by zx6r
Although I believe the Evo is down on power when running on 91 Oct, I'm still not quite convinced it's real night and day stuff. I've been mixing in the 100 Oct racing gas from 76, and according to my butt dyno, 5k to 7k feels roughly about the same (3 to 5k is strong all the time). I'd like to believe it's better but not absolutely convinced.
I'm also wondering how soon the change would kick in. I've seen some people quote 100 miles, before the ECU would readjust. So first time I mixed the gas I just waited for the change to take effect. Second time I disconnected the battery for a couple of minutes in the hope it would "reset" itself with regard to how much knock it was getting. And they both felt about the same.
All of the above is real subjective, and of course the real test would be on a dyno, or timed on the track I suppose.
Anybody have any idea as to how soon they think the Evo's ECU would "learn" the new Octane value of the gas it is using ???
Although I believe the Evo is down on power when running on 91 Oct, I'm still not quite convinced it's real night and day stuff. I've been mixing in the 100 Oct racing gas from 76, and according to my butt dyno, 5k to 7k feels roughly about the same (3 to 5k is strong all the time). I'd like to believe it's better but not absolutely convinced.
I'm also wondering how soon the change would kick in. I've seen some people quote 100 miles, before the ECU would readjust. So first time I mixed the gas I just waited for the change to take effect. Second time I disconnected the battery for a couple of minutes in the hope it would "reset" itself with regard to how much knock it was getting. And they both felt about the same.
All of the above is real subjective, and of course the real test would be on a dyno, or timed on the track I suppose.
Anybody have any idea as to how soon they think the Evo's ECU would "learn" the new Octane value of the gas it is using ???
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I got the feeling that no one had much of a clue, so you're prolly right on in that repect.
But let me get this straight:
The manual that COMES WITH the USDM version of the Evo (and is translated from Japanese) states that the car should use 98 octane, or are you referencing the Japanese manual verbatim?
No offense intended, but I don't think looking at the Japanese manual will tell us much. The car is significantly different, with different setup and likely different tuning due to different gas and different emissions regulations.
Does anyone with an 03 USDM Evo VIII have the manual handy? Does it list the minimum octane? Does it recommend higher than 91?
Arrgh! California is great except for the cost of living and the crappy (and expensive) gas!
But let me get this straight:
The manual that COMES WITH the USDM version of the Evo (and is translated from Japanese) states that the car should use 98 octane, or are you referencing the Japanese manual verbatim?
No offense intended, but I don't think looking at the Japanese manual will tell us much. The car is significantly different, with different setup and likely different tuning due to different gas and different emissions regulations.
Does anyone with an 03 USDM Evo VIII have the manual handy? Does it list the minimum octane? Does it recommend higher than 91?
Arrgh! California is great except for the cost of living and the crappy (and expensive) gas!
Originally posted by Claudius
I guess the lady you spoke to and the people SHE spoke to have no clue: the manual states to use 98 octane. This is a translation from the Japanese manual and equates to about 93 - 93.5 octane in the USA.
I guess the lady you spoke to and the people SHE spoke to have no clue: the manual states to use 98 octane. This is a translation from the Japanese manual and equates to about 93 - 93.5 octane in the USA.
Last edited by kurichan; May 15, 2003 at 07:21 PM.
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From: OC
Originally posted by kurichan
For what it's worth...
So she called the engineering department.
The conclusion was, yes, the typical Evo outputs 271 HP on 91 octane gas. Of course, she added that since it was a mass produced car, each one might be different...
For what it's worth...
So she called the engineering department.
The conclusion was, yes, the typical Evo outputs 271 HP on 91 octane gas. Of course, she added that since it was a mass produced car, each one might be different...
Especially since the specs (sometimes) state power with 98 RON fuel.
Originally posted by kurichan
For what it's worth...
Sounds like that's what Shiv is seeing...
For what it's worth...
Sounds like that's what Shiv is seeing...
Originally posted by Claudius
I guess the lady you spoke to and the people SHE spoke to have no clue: the manual states to use 98 octane. This is a translation from the Japanese manual and equates to about 93 - 93.5 octane in the USA.
I guess the lady you spoke to and the people SHE spoke to have no clue: the manual states to use 98 octane. This is a translation from the Japanese manual and equates to about 93 - 93.5 octane in the USA.
But back to the manual - it's confusing ( maybe deliberately ) as they mix 2 different terms - one minute they are talking 98 RON, the next minute they are talking "87 [(MON+RON)/2], or 91 RON may be used temporarily". To me this is akin to saying the top speed of the vehicle is 249 km/h or xx feet per sec. Yeah, you could work it out if you can be bothered, but the commonly accepted rating is (MON+RON)/2, and I think they should use it !
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From: OC
Originally posted by kurichan
Does anyone with an 03 USDM Evo VIII have the manual handy? Does it list the minimum octane? Does it recommend higher than 91?
Does anyone with an 03 USDM Evo VIII have the manual handy? Does it list the minimum octane? Does it recommend higher than 91?
Octane Requirement
Your vehicle is designed to operate on premium grade unleaded gasoline having a minimum octane rating of 98 RON. If premium grade unleaded gasoline is not available, unleaded gasoline having an octane rating of 87 [(MON+RON)/2], or 91 RON may be used temporarily. However, the performance level may be reduced.
MON: Motor Octane Number
RON: Research Octane Number
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From: Tokyo
Originally posted by zx6r
Yeah that manual sucks. In general most documents translated from Japanese suck, because they either get a non-Technical person translating them, a non-native speaker, or even worse a non-technical, non-native speaker
Yeah that manual sucks. In general most documents translated from Japanese suck, because they either get a non-Technical person translating them, a non-native speaker, or even worse a non-technical, non-native speaker
Cheers,
Paul Hansen
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Originally posted by kurichan
I got the feeling that no one had much of a clue, so you're prolly right on in that repect.
But let me get this straight:
The manual that COMES WITH the USDM version of the Evo (and is translated from Japanese) states that the car should use 98 octane, or are you referencing the Japanese manual verbatim?
I got the feeling that no one had much of a clue, so you're prolly right on in that repect.
But let me get this straight:
The manual that COMES WITH the USDM version of the Evo (and is translated from Japanese) states that the car should use 98 octane, or are you referencing the Japanese manual verbatim?
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Claudius,
That's not what I wanted to hear! Take it back and lie to me! Tell me the Evo runs great on 91 and Mitsubishi will back it! Tell me it's a misprint! Tell me ANYTHING...
If the manual is right (sounds like a sloppy translation, not a market targeted document, so who knows?) what are we 91 octane states to do? Is airplane gas unleaded? I have an airport a couple miles from where I live that sells 100LL. That might be an option...
Looks like Subaru's 500 cc bump for the STi might have been the right move. Despite being a happy WRX owner, I was really leaning toward the Evo, but if the Evo doesn't like Cali gas...?
I think Mitsu has a bit of an issue on its hands.
Will be interesting to see what Shiv accomplishes. Thrilled to hear that Mitsu is cooperating with him.
That's not what I wanted to hear! Take it back and lie to me! Tell me the Evo runs great on 91 and Mitsubishi will back it! Tell me it's a misprint! Tell me ANYTHING...
If the manual is right (sounds like a sloppy translation, not a market targeted document, so who knows?) what are we 91 octane states to do? Is airplane gas unleaded? I have an airport a couple miles from where I live that sells 100LL. That might be an option...
Looks like Subaru's 500 cc bump for the STi might have been the right move. Despite being a happy WRX owner, I was really leaning toward the Evo, but if the Evo doesn't like Cali gas...?
I think Mitsu has a bit of an issue on its hands.
Will be interesting to see what Shiv accomplishes. Thrilled to hear that Mitsu is cooperating with him.
Originally posted by Claudius
I mean the manual that comes with the US Evo 8 and that was translated from Japanese language, which, like confirmad above, recommends 98 (Japanese) octane, ie 93 octane.
I mean the manual that comes with the US Evo 8 and that was translated from Japanese language, which, like confirmad above, recommends 98 (Japanese) octane, ie 93 octane.
Last edited by kurichan; May 16, 2003 at 03:56 PM.
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Originally posted by zx6r
How do you make that out [regarding Shiv]? AFAIK the jurys still out on that one ?
How do you make that out [regarding Shiv]? AFAIK the jurys still out on that one ?
Shiv seems to be keeping quiet for now, as he must, but I think that Mitsubishi being "more responsive than any manufacturer" he's ever seen about working out the issues is pretty good evidence that issues actually do exist. Otherwise, they wouldn't be cooperating, would they?
Also, quotes like "don't worry, we're all on the side of the consumer" seem to tell us that the consumer might need an advocate.
Anyway, I don't want to debate whether there is a problem, but I don't want to buy an Evo until I know either. Guess I'll just have to let other people do the Beta testing...
Guess I'm going to stick with my WRX until next summer and wait for feedback on the STi and the Evo. All the excitement will have died down, along with the price, and we should know most of the mechanical issues for both cars. Also, more aftermarket stuff will be out!
Someone at nasioc.com just posted the info on STi owner's manual. Same thing with the EVO, 93/94 octane recommended and 91octane for temporary use only. I guess Shiv will be selling a lot of his kits.
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From: OC
Originally posted by IS2000
Someone at nasioc.com just posted the info on STi owner's manual. Same thing with the EVO, 93/94 octane recommended and 91octane for temporary use only. I guess Shiv will be selling a lot of his kits.
Someone at nasioc.com just posted the info on STi owner's manual. Same thing with the EVO, 93/94 octane recommended and 91octane for temporary use only. I guess Shiv will be selling a lot of his kits.
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From: OC
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Well, I'm a little surprised: it sounds like you cannot get 93 octane ANYWHERE in California? What was it that people were saying about Sonoco 94? Is that available at stations or only in canisters?
In Italy, there is no 98 octane (93 USA) available either, and people run it on 95 (91 US) and dont report any problems with it.
I guess it will retard the ignition a little and reduce power.
Once fully programmable ECUs and their harnesses become available in the USA, you can get it programmed to suit 91 octane gas; you'll be slightly down on power, but nothing frightening. 10 - 15 bhp less on a modified Evo with 350 - 360 bhp isnt something that will be easy to spot...
It's funny how people pull the STI card on us here every time there is something ever so slightly "wrong" with the Evo, as if the STI werent facing the very same issues...
In Italy, there is no 98 octane (93 USA) available either, and people run it on 95 (91 US) and dont report any problems with it.
I guess it will retard the ignition a little and reduce power.
Once fully programmable ECUs and their harnesses become available in the USA, you can get it programmed to suit 91 octane gas; you'll be slightly down on power, but nothing frightening. 10 - 15 bhp less on a modified Evo with 350 - 360 bhp isnt something that will be easy to spot...
It's funny how people pull the STI card on us here every time there is something ever so slightly "wrong" with the Evo, as if the STI werent facing the very same issues...
Re: 91 Oct Loss of Power
Originally posted by I-5Rally
Having a hard time deciding wether or not to get an EVO or a STI.
One question I have is that the EVO really needs 93-94 octane for max power right? How much power loss should I expect having to run 91 octane 90% of the time? If Im only going to get 250 HP because the ECU keeps pulling timing, Im surely going to go with the STI.
I currently have a WRX wagon, stock, that I love and will be keeping (wife drives). And have no experience with Mitsus.
Thanks
Having a hard time deciding wether or not to get an EVO or a STI.
One question I have is that the EVO really needs 93-94 octane for max power right? How much power loss should I expect having to run 91 octane 90% of the time? If Im only going to get 250 HP because the ECU keeps pulling timing, Im surely going to go with the STI.
I currently have a WRX wagon, stock, that I love and will be keeping (wife drives). And have no experience with Mitsus.
Thanks
STi Owners Manual....
2.5 Liter (Turbo) models
Use premium unleaded gasoline with an octane
rating of 94 AKI or higher . If premium unleaded
gasoline with an octane rating of 93 AKI
is not available, premium unleaded gasoline
with octane rating of 91 AKI or higher may be
temporarily used. For optimum engine performance
and driveability, it is recommended that
you use premium grade unleaded gasoline
with an octane rating of 93 AKI or higher.