Gas $3.98/gallon. Death to the rotary?
03-04-2012, 03:52 AM
#129
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Gas prices are one reason that I sold my RX8. 20MPG driving easy and premium sucks. My Thunderbird SC is getting the boot as well, 22 average with premium fuel. I am sticking with two cars, my 38MPG saturn and my 28MPG Formula Firebird.
03-04-2012, 09:43 AM
#132
4 DOORS FOR MORE WHORES
San Clemente, CA I paid $4.55 for premium. Not too bad.
Cruising down Pacific Coast Highway, checking out the beautiful beaches & women and doing Ortega HWY canyon runs isn't hurting yet.
Good thing my daily driver (2002 Accord 3.0L VTEC V6) gets 25MPG for my 95 mile round trip Mon-Fri commute to work. :D
Cruising down Pacific Coast Highway, checking out the beautiful beaches & women and doing Ortega HWY canyon runs isn't hurting yet.
Good thing my daily driver (2002 Accord 3.0L VTEC V6) gets 25MPG for my 95 mile round trip Mon-Fri commute to work. :D
03-11-2012, 06:28 PM
#134
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What Octane are you filling with? I fill with 93, but with these prices I'm going down to 91, which is recommended,...the manual says 87 is okay...Anyone with some info regarding 87 Octane? I don't want to damage my engine. 
Thanks!
Thanks!
03-11-2012, 06:35 PM
#135
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1) Octane is the resistance to pre-ignition, as it raises the pre-ignition temperature point.
2) This is of a concern since as compression of the air/fuel mixture increases, the mixture heats up.
3) The more compression you have, the greater the amount of heat buildup.
4) The lowest octane you can run safely is the lowest pre-ignition temperature that is still OVER the temperature that your mixture is being heated to.
A perfectly good Renesis can not safely run 87 octane. If it's above just "good", it probably can't even run safely on 89 octane. If you can run lower without issues, it means that your engine's compression is lower than optimum, and isn't heating the mixture as much as it would if the engine was "good".
So...what can you run safely? That's going to depend on the health of your engine. And it's not really going to be good news. Either you have a healthy engine and need to pay the $3 more per tank. Or you have a failing engine can can pay less per tank, but then you are getting much worse fuel economy and are wasting more than $3 per tank anyway.
If you can run 87 "without issue" then you are probably below minimum spec on your engine's compression.
If you are determined to test it, then run the tank almost dry. Ideally with 1 gallon or less remaining, but since running out of fuel OR starving the fuel pickup on a hard left turn can destroy your fuel pump and/or engine (no, not exagerating, plenty of examples) do this with an extreme attention to detail and what you are doing with the car. Put in ~3 gallons of the grade you want to test, and safely carry 1 gallon of 93+ octane. Start driving. Test slowly at increasing loads and RPMs. Pay close attention to any changes in the feel of the engine. If it begins misfiring, power loss, shaking, coughing, etc... pull over and dump in the gallon of the high grade gas that you brought along. Stop at the nearest gas station and fill up the rest of the way with the top grade. The grades will mix fine, and the effective octane is an average of the octane in there (3 gallons of 87 + 13 gallons of 93 is effectively 91.8 octane)
Do this entirely at your own risk. Don't come crying on here if you damage your engine from using 87.
In the end, it's not worth going lower. It really isn't.
2) This is of a concern since as compression of the air/fuel mixture increases, the mixture heats up.
3) The more compression you have, the greater the amount of heat buildup.
4) The lowest octane you can run safely is the lowest pre-ignition temperature that is still OVER the temperature that your mixture is being heated to.
A perfectly good Renesis can not safely run 87 octane. If it's above just "good", it probably can't even run safely on 89 octane. If you can run lower without issues, it means that your engine's compression is lower than optimum, and isn't heating the mixture as much as it would if the engine was "good".
So...what can you run safely? That's going to depend on the health of your engine. And it's not really going to be good news. Either you have a healthy engine and need to pay the $3 more per tank. Or you have a failing engine can can pay less per tank, but then you are getting much worse fuel economy and are wasting more than $3 per tank anyway.
If you can run 87 "without issue" then you are probably below minimum spec on your engine's compression.
If you are determined to test it, then run the tank almost dry. Ideally with 1 gallon or less remaining, but since running out of fuel OR starving the fuel pickup on a hard left turn can destroy your fuel pump and/or engine (no, not exagerating, plenty of examples) do this with an extreme attention to detail and what you are doing with the car. Put in ~3 gallons of the grade you want to test, and safely carry 1 gallon of 93+ octane. Start driving. Test slowly at increasing loads and RPMs. Pay close attention to any changes in the feel of the engine. If it begins misfiring, power loss, shaking, coughing, etc... pull over and dump in the gallon of the high grade gas that you brought along. Stop at the nearest gas station and fill up the rest of the way with the top grade. The grades will mix fine, and the effective octane is an average of the octane in there (3 gallons of 87 + 13 gallons of 93 is effectively 91.8 octane)
Do this entirely at your own risk. Don't come crying on here if you damage your engine from using 87.
In the end, it's not worth going lower. It really isn't.
Last edited by RIWWP; 03-11-2012 at 06:43 PM.
$4.55 a gallon ... you must use different gallons to us! were paying about £1.40 a litre over here 
03-11-2012, 09:43 PM
#139
With gas going up to what's supposed to be $5 per gallon, I think it may be a while before we see another rotary from Mazda.
I drive about 70 miles roundtrip to work daily. This car is killing me with this terrible mileage. I love the 8 but I may have to trade her in if gas goes up past $4.50 gallon. I coulkd save hundreds of dollars per month if I bought an econobox. The next rotary would have to be putting out at least 10 more miles per gallon city for me to be interested.
I drive about 70 miles roundtrip to work daily. This car is killing me with this terrible mileage. I love the 8 but I may have to trade her in if gas goes up past $4.50 gallon. I coulkd save hundreds of dollars per month if I bought an econobox. The next rotary would have to be putting out at least 10 more miles per gallon city for me to be interested.
03-12-2012, 06:43 PM
#145
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1) Octane is the resistance to pre-ignition, as it raises the pre-ignition temperature point.
2) This is of a concern since as compression of the air/fuel mixture increases, the mixture heats up.
3) The more compression you have, the greater the amount of heat buildup.
4) The lowest octane you can run safely is the lowest pre-ignition temperature that is still OVER the temperature that your mixture is being heated to.
A perfectly good Renesis can not safely run 87 octane. If it's above just "good", it probably can't even run safely on 89 octane. If you can run lower without issues, it means that your engine's compression is lower than optimum, and isn't heating the mixture as much as it would if the engine was "good".
So...what can you run safely? That's going to depend on the health of your engine. And it's not really going to be good news. Either you have a healthy engine and need to pay the $3 more per tank. Or you have a failing engine can can pay less per tank, but then you are getting much worse fuel economy and are wasting more than $3 per tank anyway.
If you can run 87 "without issue" then you are probably below minimum spec on your engine's compression.
If you are determined to test it, then run the tank almost dry. Ideally with 1 gallon or less remaining, but since running out of fuel OR starving the fuel pickup on a hard left turn can destroy your fuel pump and/or engine (no, not exagerating, plenty of examples) do this with an extreme attention to detail and what you are doing with the car. Put in ~3 gallons of the grade you want to test, and safely carry 1 gallon of 93+ octane. Start driving. Test slowly at increasing loads and RPMs. Pay close attention to any changes in the feel of the engine. If it begins misfiring, power loss, shaking, coughing, etc... pull over and dump in the gallon of the high grade gas that you brought along. Stop at the nearest gas station and fill up the rest of the way with the top grade. The grades will mix fine, and the effective octane is an average of the octane in there (3 gallons of 87 + 13 gallons of 93 is effectively 91.8 octane)
Do this entirely at your own risk. Don't come crying on here if you damage your engine from using 87.
In the end, it's not worth going lower. It really isn't.
2) This is of a concern since as compression of the air/fuel mixture increases, the mixture heats up.
3) The more compression you have, the greater the amount of heat buildup.
4) The lowest octane you can run safely is the lowest pre-ignition temperature that is still OVER the temperature that your mixture is being heated to.
A perfectly good Renesis can not safely run 87 octane. If it's above just "good", it probably can't even run safely on 89 octane. If you can run lower without issues, it means that your engine's compression is lower than optimum, and isn't heating the mixture as much as it would if the engine was "good".
So...what can you run safely? That's going to depend on the health of your engine. And it's not really going to be good news. Either you have a healthy engine and need to pay the $3 more per tank. Or you have a failing engine can can pay less per tank, but then you are getting much worse fuel economy and are wasting more than $3 per tank anyway.
If you can run 87 "without issue" then you are probably below minimum spec on your engine's compression.
If you are determined to test it, then run the tank almost dry. Ideally with 1 gallon or less remaining, but since running out of fuel OR starving the fuel pickup on a hard left turn can destroy your fuel pump and/or engine (no, not exagerating, plenty of examples) do this with an extreme attention to detail and what you are doing with the car. Put in ~3 gallons of the grade you want to test, and safely carry 1 gallon of 93+ octane. Start driving. Test slowly at increasing loads and RPMs. Pay close attention to any changes in the feel of the engine. If it begins misfiring, power loss, shaking, coughing, etc... pull over and dump in the gallon of the high grade gas that you brought along. Stop at the nearest gas station and fill up the rest of the way with the top grade. The grades will mix fine, and the effective octane is an average of the octane in there (3 gallons of 87 + 13 gallons of 93 is effectively 91.8 octane)
Do this entirely at your own risk. Don't come crying on here if you damage your engine from using 87.
In the end, it's not worth going lower. It really isn't.
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