RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   3rd Generation Specific (1993-2002) (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/)
-   -   Ethanol in gasoline (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/ethanol-gasoline-1028825/)

SoundwaveFD 03-10-13 06:53 AM

Ethanol in gasoline
 
Just wondering if I should be looking for gasoline without ethanol for my stock 3rd gen.

I cannot find Sunoco or any other 94 octane gasoline in my area, so I use Exxon 93 only.

Does ethonol content vary by grade or manufacturer? For instance 91 vs 93, or Shell vs Exxon vs BP etc?

Thanks,
Drew:nod:

ohioredrx7 03-10-13 03:38 PM

Theoretically you should. E10 will run ~4% leaner than pure gasoline. I guess it depends on Mazda's fueling strategy and whether or not they apply long term fuel trim correction during open loop operation. Perhaps someone knows for sure if they do or not.

As far as ethanol content I don't know for sure if it would vary by grade/manufacturer. When the ethanol subsidy was still on the table it was in the fuel distributor's best financial interests to mix up to the max allowed by law which was 10%. I believe the subsidy ended in 2012 so now I'm not sure if it makes sense financially for them to continue to mix in up to 10%. However there is a federal mandate in place to use a certain amount of ethanol as fuel each year so perhaps they must mix in 10% ethanol.

Anyways, according to pure-gas.org there are no ethanol free stations in your state (assuming you live in Delaware) but there are some right across state lines in Maryland.

RotaryEvolution 03-10-13 03:55 PM

there is no fuel trims on the stock ECU... treat this car as a 1st generation electronic fuel injected car. closed loop enrichment based off the narrowband O2 sensor which does not affect hard load situations is about the extent of it's ability, all other fuelling is hard mapped and taken directly from correlation tables.

remember, a narrowband is useless beyond about a full point above and below 14.7:1 AFR, in boost that figure is worthless. you have closed loops moderate fuel trimming while cruising at steady speeds but that is about all.

ideally you would want the least amount of ethanol as possible but you will never find a station with pure gasoline content. ethanol is like a meat filler for Mcdonald's hamburgers. the stock mapped ECU is also basically set to work just fine on E10 fuels, because ethanol has been a fuel additive since before you were born(long before these cars were ever built).

ideally pump gas will likely always have close to the same mixing ratios, because all car manufacturers specify their tunes based on that mix. if the gas suppliers were allowed to start mixing up to say 30% ethanol, there would be a rash of engine failures and then the finger pointing would begin and wallets would open, otherwise the general public would find out why they had a $5k bill on their hands X100's of thousands(billions of dollars in damages just to skimp). ethanol is cheaper to produce than gasoline and likely always will, because it is a renewable energy source.

cewrx7r1 03-10-13 10:39 PM


Originally Posted by RotaryEvolution (Post 11401880)
). ethanol is cheaper to produce than gasoline and likely always will, because it is a renewable energy source.

:icon_tdow

That is wrong. It currently takes more total energy to produce ethanol than what it produces when burned. You have to add in all the cost: planting, fertilize, harvest,
and the cost of converting the corn to ethanol.

It is the government subsidies that make it available, not true costs.

Were gas gasoline comes out on the positive side.

Not until 1988 was ethanol added to gasoline in the USA.

RotaryEvolution 03-11-13 09:58 AM

ok, i should say that it will likely always be CHEAPER than gasoline since it is renewable.

Monkman33 03-11-13 11:01 AM

Again. No. Its actually much more expensive. B government subsidies is what brings the price down. Ethanol is not the future.

RotaryEvolution 03-11-13 11:41 AM

not for the end user it isn't.

realistically you can make methanol yourself with just a still and some calories. of course it is regulated because it is also considered "moonshine" and is a consumable form of alcohol and subject to ATF. methanol being wood fuel, ethanol being rice/corn fuel. main reason for ethanol being expensive to produce is it takes diesel fuel to transport to distilleries. if the refinery process was less reliant on fossil fuels to produce, not to say if the trucks were using the same fuel they produced they would consume nearly the same amount they produced from a truckload, maybe less. if the refinery and distillery were all located on the same location as the harvest, it would be quite a bit more efficient.

i never said it was the future but it will always have an alternative fuel status. if every car ran on ethanol/methanol it would outgrow a renewable resource, because there is no way we could support only fuel crops or tree crops to power every car out there.

every taxi in las vegas is a hybrid vehicle(regulated to be). they run on E85, propane or are hybrid gas/electric.


All times are GMT -5. The time now is 11:46 PM.


© 2024 MH Sub I, LLC dba Internet Brands