What is the lowest octane an RX8 can safely use?
#1
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What is the lowest octane an RX8 can safely use?
I seem to have noticed my 8 runs better on 91 octane when compared to 93 octane. This is a seat of the pants thing, but what I really want to know is can I run 89 octane? My gas mileage seems to be better (tested two tanks of each) with 91 octane (avg 19mpg) vs 93 octane (avg 16mpg), but I can't really say if it is better because the weather has been cooler or I've been driving a little more highway, etc. I've read on this forum that rotaries run cooler with lower octane, maybe that is what accounts for the differences, I dunno but I'd like to see what happens with the lowest octane that is "safe" for the engine.
TIA,
Alex
TIA,
Alex
#3
I ran a tank of 87 without any problems. It was during the gas-crisis after Katrina and after waiting an hour to get into the station all they had was 87. And I was empty.
#5
I bought mine the end of June last year. Followed the recomendations and used premium, until it jumped up to around $3.60/gal. Seeing as how both my rx7s ran just fine on 87, I tried first 89, then 87, and have been running 87 for months now. Car runs just fine.
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87 is perfectly fine. An NA tuned Renesis, by Mazsport, has also reflected it is the best for power.
I started mine on 93, then backed off to 89...I'm at 22,000 miles and have run the car on 87 for the past 8,000 with no issues whatsoever.
I started mine on 93, then backed off to 89...I'm at 22,000 miles and have run the car on 87 for the past 8,000 with no issues whatsoever.
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Yeah, like ZoomZoomH said, cars nowadays are smart enough to know when it's detonating. There's this neat little thing called a knock sensor...
Anyways, i dunno about getting more power with 87 octane like RedDevil said... but lower octane means retarded timing... which means reduced performance.
But wait, does a Renesis have timing? OMG wow... I actually never thought about that. ^^
Anyways, i dunno about getting more power with 87 octane like RedDevil said... but lower octane means retarded timing... which means reduced performance.
But wait, does a Renesis have timing? OMG wow... I actually never thought about that. ^^
#14
I've been buying 93, wishing there was a mid-grade 91, but instead it is 89. But after the advice to run it at 87, WOW, that will save me $$$ - thanks all!
Can anyone help to define ***good*** gas? I always shop price, am I being stupid?
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Can anyone help to define ***good*** gas? I always shop price, am I being stupid?
#16
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yeah, but that adds up to like $124 pear year! :p
heh...if the difference of $2-3 per tank is making that big of a difference, then perhaps a more fuel economic car is more suitable...
heh...if the difference of $2-3 per tank is making that big of a difference, then perhaps a more fuel economic car is more suitable...
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#17
The "risk" ? What risk?
I've had plenty of people here tell me to use 87. I've had my dealer REQUEST that I use 87 over higher octane fuels to avoid carbon deposit build ups. I've read detailed articles explaining why running 87 in a rotary creates a hotter flame front. An article even referenced a discussion with an engine designer from Hiroshima where the car was built, and HE said to run 87 3 out of 4 tanks with the 4th just being for the cleaning additives. I've been running 87 for 15,000 miles with zero engine trouble.
I've had plenty of people here tell me to use 87. I've had my dealer REQUEST that I use 87 over higher octane fuels to avoid carbon deposit build ups. I've read detailed articles explaining why running 87 in a rotary creates a hotter flame front. An article even referenced a discussion with an engine designer from Hiroshima where the car was built, and HE said to run 87 3 out of 4 tanks with the 4th just being for the cleaning additives. I've been running 87 for 15,000 miles with zero engine trouble.
Last edited by Raevik; 03-14-2006 at 01:49 PM.
#19
Ok, true enough Zoom ZoomH, but what is considered "quality"? I mean I cannnot tell the difference, I really doubt price is it...are you saying that quality = higher octane? I can live with that. But I think quality may be getting confused with brands.
Asheville has lots of BP stations - good? How about Hot Spot? Enmark? Please don't make me shop at Exxon/Mobil - my visit to the Prince William Sound in Alaska made me swear off their products. So far I have only fed it with 93 octane, nothing too good for my baby, ya know?
Asheville has lots of BP stations - good? How about Hot Spot? Enmark? Please don't make me shop at Exxon/Mobil - my visit to the Prince William Sound in Alaska made me swear off their products. So far I have only fed it with 93 octane, nothing too good for my baby, ya know?
#20
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Originally Posted by Raevik
The "risk" ? What risk?
even poor quality 91+ will be at least 89 or so, which is well within the 'OK' fuel octane range for the RX-8
and tominavl, basically to me, a 'quality' gasoline would come from a gas station that is well kept, hopefully a well known regional/national brand, and that prices are not RIDICULOUSLY cheaper than competitors in the area.
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BP, Shell, etc...basically I think he means to stick with the name brands and away from the unaffiliated or small company, like Joe's Garage, Gas and Gum.
As for the 87 providing more power. I can't prove that nor would I claim to see a difference between 87 and 93 in my car. The Mazsport car was ECU tuned and Scott claimed 87 provided the best power while even costing less. I'm inclined to trust Scott so there's where my statement came from.
As for the 87 providing more power. I can't prove that nor would I claim to see a difference between 87 and 93 in my car. The Mazsport car was ECU tuned and Scott claimed 87 provided the best power while even costing less. I'm inclined to trust Scott so there's where my statement came from.
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Originally Posted by Raevik
The "risk" ? What risk?
I've had plenty of people here tell me to use 87. I've had my dealer REQUEST that I use 87 over higher octane fuels to avoid carbon deposit build ups. I've read detailed articles explaining why running 87 in a rotary creates a hotter flame front. An article even referenced a discussion with an engine designer from Hiroshima where the car was built, and HE said to run 87 3 out of 4 tanks with the 4th just being for the cleaning additives. I've been running 87 for 15,000 miles with zero engine trouble.
I've had plenty of people here tell me to use 87. I've had my dealer REQUEST that I use 87 over higher octane fuels to avoid carbon deposit build ups. I've read detailed articles explaining why running 87 in a rotary creates a hotter flame front. An article even referenced a discussion with an engine designer from Hiroshima where the car was built, and HE said to run 87 3 out of 4 tanks with the 4th just being for the cleaning additives. I've been running 87 for 15,000 miles with zero engine trouble.
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Just use 98 octane like me, then you dont need to worry at all
I cant believe you guys moan about petrol prices over there.... here in the UK it costs me £60 to fill my tank. You got it eeeeeasy!!
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