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What types of fuel work best in your toy home? Also do you change octane depending on the terrain you're going through.

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I run the middle octane. Its only 10 cents a gallon more then regular. I think it helps but its hard to tell. Its not a drastic difference. Saw a special nozzle at a local 76 station the other day. It read "Not a 76 product-Racing Fuel 110 octane" $8.00 a gallon! Here in California there's always something to climb so I figure for 10 cents more a gallon if it helps its worth it.

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Use the lowest possible octain avalable - if your truck runs good (no spark knock). The lower the octain the higher your gas mileage. Higher octain actualy has less energy units. The higher octain's purpose is to stop spark knock, or the piston fireing under compresion befor spark.

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Use the lowest possible octain avalable - if your truck runs good (no spark knock). The lower the octain the higher your gas mileage. Higher octain actualy has less energy units. The higher octain's purpose is to stop spark knock, or the piston fireing under compresion befor spark.

WOW that is an eye opener. After reading your post I did a google search on the subject and found the same exact answers. Here is one http://www.wanderings.net/notebook/Main/IsHighOctaneGasWorthTheMoney and http://www.state.mn.us/mn/externalDocs/Commerce/Gasoline_Octane_Facts_102902052227_OctaneFacts.pdf

I have been wrong all this time assuming a higher octane would give me more horsepower and therefore better mileage. Thanks for setting us straight! One thing I read is that the higher the octane the more energy it requires to ignite the fuel. I am still in the WOW mode.

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WOW that is an eye opener. After reading your post I did a google search on the subject and found the same exact answers. Here is one http://www.wandering...asWorthTheMoney and http://www.state.mn....OctaneFacts.pdf

I have been wrong all this time assuming a higher octane would give me more horsepower and therefore better mileage. Thanks for setting us straight! One thing I read is that the higher the octane the more energy it requires to ignite the fuel. I am still in the WOW mode.

Haha...I have been trying to convince my GF of this forever! "Premium" gas doesn't mean BETTER gas! It just means it will resist pinging better, and that is almost entirely dependent on your engines compression ratio. You don't need mid-grade gas till your motor is up over 9.5:1 compression ratio. 93 octane is for hi performance engines sporting 10.5+. Our poor lil Toyos 22RE's sport around 9.0. However, in high mountain areas the fuel ratio can lean out enough where bumping up to the next highest octane level can help. This happened to me in CO.

Basically, just listen to your engine. It will tell you what it needs. But for normal driving, 87-89 is just fine.

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I live in Vancouver BC Canada. Last time I drove to Montana I was surprised to find out the regular gasoline there only has a 85.5 octane rating (where mostly in the west coast regular gas rates 87). Would that be enough for our Toyota MH?

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I noticed the same thing driving thru Idaho and Utah from Oregon. Kind of startled me; I even refused to fill-up at a station, thinking it was an inferior product. The next station had the same fuel ratings, so I figured that the altitude may have something to do with it. Crossing the Great Divide (800 miles?), I didn't experience a noticeable drop in mpg's. The hardest climb was Medicine Bow (I-80 East) between Laramie and Cheyenne, Wyoming. 35 mph with a Sunrader V6 Automatic. And that was with the 85 octane.

Edited by toyota222

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All the 22RE's and V6 have knock sensors that listen to the engine for you and crank the timing back if they detect a knock this may or may not be a good thing climbing the hills where you need all the power you can call up so a little upgrade on the the fuel in the hills would help. But I agree you don't need hi test it's a waste of money for any thing less then a high performance car.

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The pump listed octane is lower as you climb into higher elevation areas. It still works just fine because at the higher elevations there is less air density to compress in the engine cylinders, thus the compression pressure goes down (even thought the compression ratio remains the same). What that means is that the risk of predetonation is lowered in higher elevations, also it is lowered in cooler air temperatures. I suppose if you filled up with low octane in the mountains and drove down into a hot low elevation valley you might get more detonation. Predetonation is the combustion chamber flame front exploding rapidly before the piston is past top dead center, thus trying to "knock" the piston backward (reverse rotation) instead of forward. The sound of "knocking pinging" are all the metal parts from your piston crown, to the piston pin, to the piston rod, into the crank bearing, being slammed backwards by the expanding flame pressure. Higher octane fuel actually "lights" & "burns" slower so the flame front does not make maximum pressure until the piston has passed over the top of the stroke and is starting its downward movement. It is a little like trying to push a child on a swing while they are still coming back toward you instead of timing the push as the swing starts swinging away from you.

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I agree with the recommendation to use the lowest octance, as long as it's 87 which is what my manual calls for. I never use the 85, and I really don't like to use the ethanol blends if I can avoid them. I haven't kept careful records, but it seems clear that a tankful of the ethanol blend goes much faster than straight gasoline. Unfortunately, it's getting harder and harder to avoid the ethanol blend gas, especially when we're down in the states. I tried a few tanks of high test on a trip across Canada last summer and actually got about 2 MPG worse mileage with it. Wayne

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There are less BTU's (British Thermal Units) in ethanol than in gasoline. BTU's are a unit of heat, the more heat available per gallon the further you can drive per gallon. Diesel has way more BTU's than gasoline and propane has way less, thus they get more or less MPG hauling the same weight. This is where congress needs to go take a science class before making laws, as they want more ethanol put into gasoline and more miles per gallon. The more ethanol you put into a gallon of gas the less MPG you will get, all other things being equal.

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Is there a way you can tell which gasoline stations do NOT add ethanol to their fuel before you pull in to fill-up? Or is it a federal mandate to add 10% ethanol to all petroleum sold in the US? Thanks!

There are less BTU's (British Thermal Units) in ethanol than in gasoline. BTU's are a unit of heat, the more heat available per gallon the further you can drive per gallon. Diesel has way more BTU's than gasoline and propane has way less, thus they get more or less MPG hauling the same weight. This is where congress needs to go take a science class before making laws, as they want more ethanol put into gasoline and more miles per gallon. The more ethanol you put into a gallon of gas the less MPG you will get, all other things being equal.

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I think they have to post it. Here in Maine it's 10% it does cheese me to pay for 10gls. of gas and only get 9 nor do I think burning food (corn) is the answer. My ideal of the proper use for alcohol is in a good glass of wine.

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Well !

Explain this.

I have a 2001 Toyota Tacoma Extend cab SR 5. When It was a couple yrs old I took it to Louisville Ky ( around 6 -7 hr driving time there) I used low octane gas and averaged 20 MPG.

there and back. The next yr I went the same route to same place and used Premium gas and averaged 25 MPG there and back. After the premium was all used up I went back to the regular gas and my miles per gal. drops to 20 MPG. When I am planning a longer trip I use up most of the reg gas and then fill up with premium and it seems as I always get the 25 MPG. I know that this is a FACT and goes against the grain as to what has been posted in this thread.

'homer'

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There are so many variables when it comes to this subject. If you buy a less quaility gas most of the time you will not get your highest MPG compaired to using a higher quaility gas such as shell or cheveron. The higher octane can help if you engine can use it to create more power which could equal more MPG. If you engine can sense that your running a higher octane and advance your engine timing more this will gain you more power. Most of these older engines do not even have knock sensors or good systems that can detect this kind of tuning. That being said the higher quailty of gas can burn more complete and also if you had dirty injectors to begin with the higher quailty gas will help clean them out. Like I said there are way to many variables to say any 87 octane gas will get your more MPG the any 91 octane gas.

On another note I will be running my 1985 toyota dolphin on E85 ethonal fuel this trip will at least as many places as I can get it around the country. I have it all mapped out and it looks like I will have to get 3-4 tanks of reg gas along the way. E85 fuel is 105 octane and also burns about 20 degrees cooler then gas. Its a much cleaner fuel that keeps the inside of your motor clean and your injectors clean too. I am installing a converter on mine so I can run straight E85 but you can also mix E85 with stright gas into a stock setup. I usally mix about 50% gas to 75% gas with 50%-25% of E85. This mixture will raise your octane rating in the mid to upper 90's. There are also study's out there that show ethanol in a mixture around 30-40% E30-E40 will get a lot better MPG then with just E10 which is whats just about at every pump in the country. It has to do with the chemical mix of the two and allowing a more complete burn.

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I've learned that people (myself included) can be passionately convinced of the "truth" of something that is entirely erroneous and it is easy to point to anecdotal evidence to support an incorrect hypothesis. For example, I long believed that higher octane fuel ("ethyl" in my youth, from the addition of tetra ethyl lead) gave more power and higher fuel economy. But I am a believer in the scientific method, and science just doesn't support that belief. There are lots of web sites that can give you good, correct information about fuel octane issues. The State of Oregon has some very good and correct (but concise and not terribly detailed) information about octane here. The scientific truth is that, in most properly tuned engines, any octane rating above that which prevents "pings" or "knock" (preignition caused by the fuel igniting from compression before the spark plug sparks) adds no performance benefits and does not increase the life of the engine. If higher octane rated fuel truly does increase your performance or fuel economy, you probably need a tune up. However, in some engines that have electronic knock sensing, there may be some slight benefit to using a higher octane rated fuel.

As to E85, even the ethanol fuel industry admits that it may decrease fuel economy by about 2% in fuel injected vehicles. The U.S. Department of Energy gives much gloomier information, stating that flex fuel vehicles usually have a 25% to 30% loss in fuel economy when running on E85 because of its lower energy content. The Wikipedia article on the subject points out that E85 has 30% less energy by volume than conventional gasoline.

I'll stick with good ol' gas - I even avoid 10% ethanol when I can, since the Department of Energy acknowledges that it will reduce fuel economy by 3% - 4%.

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Very true, good info.

Premium or higher octain fuel is used in a high compresion engine to prevent spark plug knock or predetonation. With lower octain fuel the engine fires under compresion actual fireing and trying to force the pistion back down on a upward cycle. The higher octain has less energy - less explosive - less energy units. than lower octain to prevent spark plug knock. Less energy less milage, more expensive (it really should be a cheeper fuel).

Also adding as little as 10% ethinal to the gas causes a 15% increase in fuel demand. e85 is 60%. The differance in a multifuel car is a larger fuel pump and larger injectors to handle the increase of fuel.

Dale

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Burton, Please keep us posted on the E85 usage.

My concern with using E85 in a vehicle this old is the compatibility of E85 with fuel system components, i.e. rubber seals, hoses, etc.

John Mc

88 Dolphin 4 Auto

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You are right by saying that higher octane fuels will not give you more power but it's not the fuel that's holding you back it's your engine. Yes if you have a bone stock motor run the lowest octane it can handle but also remember that higher octane helps keep down the heat. So if you are thinking about driving across death valley (which I am in a month) and you camper already has trouble staying cool you might want to bump up to high grade that tank.

Yes most of the 10% ethanol gas at the pumps today is crap. This is most of the reason why ethanol has a bad name. What happens is the oil companies are mixing in 10% at the factory and putting it into the pumps as 87 octane. Ethanol at 100% is 115 octane so if you adding 10% into regular gas that is a really good octane booster. So really there are cutting corners even more and really taking like a dirty 84 or 85 octane gas and putting 10% ethanol in and there you have it thats the cheap grade and just about every pump in the country. Oh and even better the rich oil companies are the ones that get the gov tax criedt for mixing in bio fuels, win win for them I guess. The only kind of pumps you will not find this setup at is blender pumps. These are getting more popular but still mostly in the midwest now. What a blender pump is is it has one tank of staight gas and another tank of straight ethanol underground. On the pump you can select e0, e10, e20, e30, e50, and e85. The thing with this is the e0 still has to be 87 octane by law if it says it on the pump so if you select e10 from there you will be getting a much better quality e10 fuel then a non blender pump and also the oil company doesnt get the tax criedt and that money can be used to build new blender pumps.

Now with E85 it is 105 octane and burns much cooler and cleaner then gas. In the summer time it is at full 85% ethanol 15% gas. They also have blends for colder areas of e74, and e70. It will still say e85 on the pump but in the winter time your getting one of those two blends. Yes flex fuel cars have larger fuel injectors and maybe a few other parts but are just about the same as a non flex fuel car. It cost the car makes less then $100 more to make it a flex fuel car. The problem is we are wasting the energy. There is already companies out there that make motor's that can run on both gas and ethanol but if run on ethanol have much more power and in return get about the same MPG as when run on gas. Here is a great paper on this subject its a little hard to follow at times but if you know a thing or two about motors you should read it. http://delphi.com/pdf/techpapers/2010-01-0619.pdf

waiter I will keep you posted on the E85 update for my 1985 dolphin. If I get my interior done by next weekend I am going to drive to southeren CA to drop off my dolphin to aero tanks to get the larger 30 gal installed. It does cost a little bit but I need to either clean or get a new tank with mine as it is because it was sitting for 5 years and the guy told me he already had to drop the tank once because the rust cleaned the fuel pump sock. So I would really just like to get a brand new tank and with taking this 8000 mile + 30 day trip next month I am trying to use E85 as much as possiable so a larger tank would help for sure.

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If I get my interior done by next weekend I am going to drive to southern CA to drop off my dolphin to aero tanks to get the larger 30 gal installed.

I am really anxious to hear how the 30-gallon tank installation goes. That is one of the big drawbacks of the Toy Homes from my perspective. Even though they get good gas mileage, a 17 gallon tank means fill-ups every 200 miles or so to be safe. I've put a jerry can on the back to give me a little cushion, but it would be great to have a larger tank. Please put a note in Fuel Tanks and ETC when you've completed the swap!

I hope you enjoy your first long trip with the Toy! I'm about to take off on my first real trip in a week - but it will only be 2000 to 2500 miles. Nanaimo, baby!

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The only thing cooler is the cylinder temps during the firing cycle reducing engine coolant temp is doubtful internal combustion engines are inefficient and produce lots of wasted heat no matter what they burn. The same effects can be achieved by injecting water instead of ethanol if you want to reduce spark knock or cool cylinder temps common trick on high HP diesels. There flat is not as much energy (heat) in any thing burning ethanol the flex fuel cars/trucks dump more fuel into the cylinders they have to, to maintain the power there is no way around it the energy value just is not there.

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The only thing cooler is the cylinder temps during the firing cycle reducing engine coolant temp is doubtful internal combustion engines are inefficient and produce lots of wasted heat no matter what they burn. The same effects can be achieved by injecting water instead of ethanol if you want to reduce spark knock or cool cylinder temps common trick on high HP diesels. There flat is not as much energy (heat) in any thing burning ethanol the flex fuel cars/trucks dump more fuel into the cylinders they have to, to maintain the power there is no way around it the energy value just is not there.

I understand what your saying about in cylinder temp's and having to do with coolant temps. I know that it's not the largest impact on the overall coolant temp but it does affect it. If you look at a lot of air cooled motorcylces they suggest running higher octane to help keep the heat down. This is the same thing just air carrying the heat away instead of water. Everything is cooler on E85 the EGT's are around 200 degrees cooler. Less heat everywhere add's up.

As to not being able to get better MPG or more energy out of E85 I highly recommend you read that link that I had posted it's a great write up. Yes the energy BTU rating is still lower then gas I know what you saying but you can build motor's that are smaller then motor's ment for gas and build them with more power so that they make the same power as the larger gas motor. Let's say you have a truck that runs on gas and has a v-8 engine and makes 250hp. What if you make a v-6 engine setup of e85 that made 250hp. rough outline of where I am going with this but that is what I am saying about getting more out of ethanol.

Edited by burton9010

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Air cooled motor cycle engines are cooled by fuel, they run a very rich mix that is why comparatively small engines get poor mileage. To me a 1.5 liter 700# rider and motorcycle getting 30 MPG is pretty bad when a 1.5 liter car can get better then 35MPG. You are correct small engines with lots of HP needing to cool EGT and one of the main reasons for that is turbo/super chargers and a comparatively high fueling rate. High fueling rates particularly with a high performance diesel have to have some type of cylinder cooling to prevent a melt down usually done with water. It takes 7 times the energy to change water to steam as it does to take it from ice water to a boil so it sucks up huge amounts of heat changing to steam. Ethanol will lower cylinder temps as will as water and high test fuel but in any thing other then a performance application the need is not there so for the best bang for the buck is plain old regular in an every day driver.

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All I am trying to say is there is a link between running higher octane fuels and being able to controll engine temps not just in cylinder pinging. I have a buell motorcycle which has a air cooled harley motor in it and they are known for there down flaw off having a hard time of getting rid of heat. If you are ever in traffic or low speeds the cooling fan would run non stop trying to cool the motor. When the bike was tuned on E85 it ran much cooler and the cooling fan would almost never kick on. Yes for the everyday driving on your motorhome you will be fine running the cheap grade gas as long as you dont get any ping out of the motor. I am just saying if your in for a long day of driving with big hills or high outside temps it might help you running high grade that day even if your not experiencing pinging.

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