Lets have a discussion about Fuels, unleaded/leaded/octane levels
I see leaded/unleaded racing fuel, 100+ octane around, good, bad, ?
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depends on your motor Brad. In your case, BAD!
Your motor was designed (and hopefully optimized) with a specific combination of cylinder head, camshaft, compressison ratio, ignition timing, carb calibration and fuel octane. At best, any fuel higher in octane is just a waste of money, but more than likely it would result in lower power & poorer fuel economy.
I would never recommend a street driven car to be set up to run on race fuel. What a pain in the butt it would be to acquire fuel while out on the open road.
There's a reason why it is referred to as race fuel.
your friend on the DTBB
Your motor was designed (and hopefully optimized) with a specific combination of cylinder head, camshaft, compressison ratio, ignition timing, carb calibration and fuel octane. At best, any fuel higher in octane is just a waste of money, but more than likely it would result in lower power & poorer fuel economy.
I would never recommend a street driven car to be set up to run on race fuel. What a pain in the butt it would be to acquire fuel while out on the open road.
There's a reason why it is referred to as race fuel.
your friend on the DTBB
I agree with George. Unless your engine needs it because of a high compression rate, pinging, dieseling when you turn it off, etc... then it is a waste of money.
The typical octane boosters you buy at the auto parts store like 108+, etc... are misleading. They only raise the octane a point or two. So if you start out with 91 octane you end up with 91.2 if you mixed it with the correct amount of gas.
If your engine doesn't require it, save your money.
For those that do need a boost I have had a good deal of success using Toluene as an octane booster.
http://patriot.net/~jonroq/Tech/octane2.html
The typical octane boosters you buy at the auto parts store like 108+, etc... are misleading. They only raise the octane a point or two. So if you start out with 91 octane you end up with 91.2 if you mixed it with the correct amount of gas.
If your engine doesn't require it, save your money.
For those that do need a boost I have had a good deal of success using Toluene as an octane booster.
http://patriot.net/~jonroq/Tech/octane2.html
Funny thing about octane boosters... They keep the fuel from ignighting until the spark fires it. You can pour some booster on concrete and it will not burn.
That is how it works Bill. Wwhat you want to do is put something in that has a higher ignition temperature. Pretty much anything will burn at a high enough temperature and the presense of oxygen. Take for instance lead. Believe it or not it does burn. But it has to be really hot first. That is also why they put aluminum shavings in some explosives. It raises the detonation temperature. Nitrogen compounds work pretty well but you will never pass emision test using them. Way to much Nox production. But nitrated methane makes a jim dandy fuel. Expensive, but it makes a bunch of pony power.
I have mentioned this before, But Av Gas (airplane gas) is a very viable option. It has additives in it that are desirable for cars not driven often, such as fuel stablizers and detergents to keep fuel systems clean. Best of all it is much cheaper than race fuel (figure about $1 more a gallon than pump premium) yet delivers the same desired effect. My preferred fuel is the 100/130 grade, but there is a catch. Since Avgas is not (supposed to be) used in cars it is not subject to road tax, thus making it illegal to pump directly into a car. To work aroud this, show up at your small local airport with some 5 gallon cans or 55 gallon drum and tell them it's for "your boat" and pump away. Here is a link for some info on Avgas.
Ron
Ron
We must have different laws in California, because I use av 100 and I just taxi down the side road right to the pumps pay with a credit card enter some numbers like I had tail numbers and the pump is turned on. I just pull the hose to my car and pump. Its open 24hrs.
Thanks
Dennis
Thanks
Dennis
Since the subject of Av-Gas was brought up, I thought I would share this essay by Tim Wusz, not as a rebuttle, but to share the precautions Tim mentions in regards to using Av-Gas in automobiles.
Racing Gasoline Verses Aviation Gasoline
written by, and thanks to
Tim Wusz
76 Products Company
I am going to attempt to address the controversy of aviation gasoline verses racing gasoline for use in race cars. Some racers use aviation gasoline which is fine for some applications but does have shortcomings. There are several grades of aviation gasoline (avgas) that we must identify before going any farther.
1. Avgas 80/87: this product is used in low compression ratio aircraft engines, contains little or no lead, is red in color, and should not be used in any automotive engine due to a low motor octane number of about 80.
2. Avgas 100/130: this product that can be used in some automotive engines. It has both research and motor octane numbers slightly over 100. Avgas 100/130 is green in color, contains four grams of lead per gallon, and is becoming harder to find.
3. Avgas 100 LL: the LL stands for "low-lead" which means two grams per gallon, low compared to the avgas 100/130 that it was designed to replace. It has research and motor octane numbers very similar to the 100/130 product previously discussed. The color is blue. This product sometimes has a high level of aromatics which can contribute to lazy throttle response and dissatisfaction of the consumer.
4. Avgas 115/145: this product was developed for high performance piston aircraft engines used in world war II and in the Korean war. It is very hard to find anymore due to lack of demand although it is of very high octane quality. The color is purple.
The remainder of this discussion will assume that our basis for comparison with racing gasoline is avgas 100/130 and/or 100 LL since they are both available and have acceptable octane quality for limited applications. When the word "avgas" is used, it will refer to avgas 100/130 or 100 LL.
Avgas is less dense than most racing gasolines. Instead of weighing about 6.1 to 6.3 pounds per gallon like racing gasoline, it weighs 5.8 to 5.9 pounds per gallon. The racer must compensate for this by changing to richer (larger) jets in the carburetor when changing from racing gasoline to avgas.
The other major difference is octane quality. Avgas is short on octane compared to most racing gasolines. Many racing engines with "quick" spark advance curves or with no centrifugal advance have more spark advance at low rpm than avgas and some racing gasolines can handle. The result is detonation, especially during caution periods in circle track racing because all of the spark advance is "in", rpm is low, and part throttle air fuel ratios are too lean for the operating conditions. If the driver does not "work" the throttle back and forth, pistons can be "burned" which melts away part of the aluminum piston material. Inadequate octane quality is one of the quickest ways to destroy an engine. Pistons can be severely damaged during one acceleration where detonation is present and the racer may not know what is happening until it is too late.
For maximum performance and power from a racing engine, racing gasoline will normally provide better performance than avgas. Avgas can be a good gasoline for some applications, but since most racers do not know the octane requirement of their engines, they would be better off with a "real" racing gasoline that will give them the overall resistance to detonation that they need to protect their investment. If someone has spent from $15,000 to $50,000 or more on their racing engine, it is foolish to cut corners on gasoline be sure you have a gasoline with adequate octane quality.
Racing Gasoline Verses Aviation Gasoline
written by, and thanks to
Tim Wusz
76 Products Company
I am going to attempt to address the controversy of aviation gasoline verses racing gasoline for use in race cars. Some racers use aviation gasoline which is fine for some applications but does have shortcomings. There are several grades of aviation gasoline (avgas) that we must identify before going any farther.
1. Avgas 80/87: this product is used in low compression ratio aircraft engines, contains little or no lead, is red in color, and should not be used in any automotive engine due to a low motor octane number of about 80.
2. Avgas 100/130: this product that can be used in some automotive engines. It has both research and motor octane numbers slightly over 100. Avgas 100/130 is green in color, contains four grams of lead per gallon, and is becoming harder to find.
3. Avgas 100 LL: the LL stands for "low-lead" which means two grams per gallon, low compared to the avgas 100/130 that it was designed to replace. It has research and motor octane numbers very similar to the 100/130 product previously discussed. The color is blue. This product sometimes has a high level of aromatics which can contribute to lazy throttle response and dissatisfaction of the consumer.
4. Avgas 115/145: this product was developed for high performance piston aircraft engines used in world war II and in the Korean war. It is very hard to find anymore due to lack of demand although it is of very high octane quality. The color is purple.
The remainder of this discussion will assume that our basis for comparison with racing gasoline is avgas 100/130 and/or 100 LL since they are both available and have acceptable octane quality for limited applications. When the word "avgas" is used, it will refer to avgas 100/130 or 100 LL.
Avgas is less dense than most racing gasolines. Instead of weighing about 6.1 to 6.3 pounds per gallon like racing gasoline, it weighs 5.8 to 5.9 pounds per gallon. The racer must compensate for this by changing to richer (larger) jets in the carburetor when changing from racing gasoline to avgas.
The other major difference is octane quality. Avgas is short on octane compared to most racing gasolines. Many racing engines with "quick" spark advance curves or with no centrifugal advance have more spark advance at low rpm than avgas and some racing gasolines can handle. The result is detonation, especially during caution periods in circle track racing because all of the spark advance is "in", rpm is low, and part throttle air fuel ratios are too lean for the operating conditions. If the driver does not "work" the throttle back and forth, pistons can be "burned" which melts away part of the aluminum piston material. Inadequate octane quality is one of the quickest ways to destroy an engine. Pistons can be severely damaged during one acceleration where detonation is present and the racer may not know what is happening until it is too late.
For maximum performance and power from a racing engine, racing gasoline will normally provide better performance than avgas. Avgas can be a good gasoline for some applications, but since most racers do not know the octane requirement of their engines, they would be better off with a "real" racing gasoline that will give them the overall resistance to detonation that they need to protect their investment. If someone has spent from $15,000 to $50,000 or more on their racing engine, it is foolish to cut corners on gasoline be sure you have a gasoline with adequate octane quality.
I agree with everything Mr. Wusz states, but note he never mentions any of the superior charecteristics nor does he mention that it is still superior to pump gas. But that it to be expected since he sells race fuel it is his job to do the best he can to down play Avgas. So if I read his statement correctly, I'm getting a lighter fuel that far out performs pump gas for a couple of bucks a gallon cheaper.
Ron,
I didn't post that to rebutt you. Please notice, the heading is Race Gas verses Av Gas, not Pump Gas verses Av Gas.
The thrust of his essay is that race gas makes a better race gas! hard to believe ....lol....
I'll be happy if people read his comment that the motor needs to be jetted to switch from one to the other.
When you write Av Gas is a better fuel than pump gas, better is a subjective term. Its only better if the motor needs the extra octane. Otherwise it is money down the hole, or worse yet, less bhp & fuel economy, for more money.
So Av Gas has limited application, a motor that won't run on 92 octane, but doesn't need race gas.
Your friend on the DTBB
I didn't post that to rebutt you. Please notice, the heading is Race Gas verses Av Gas, not Pump Gas verses Av Gas.
The thrust of his essay is that race gas makes a better race gas! hard to believe ....lol....
I'll be happy if people read his comment that the motor needs to be jetted to switch from one to the other.
When you write Av Gas is a better fuel than pump gas, better is a subjective term. Its only better if the motor needs the extra octane. Otherwise it is money down the hole, or worse yet, less bhp & fuel economy, for more money.
So Av Gas has limited application, a motor that won't run on 92 octane, but doesn't need race gas.
Your friend on the DTBB
100LL which is blue is the most comon fuel you will find at the airports. Keep in mind Shell payed up on some bad lawsuits from ruining engines and prop governers with pure synthetic oil. If you are running pure synthetic oil (blend generally ok) it can not break down the lead.
You are not paying road tax with this fuel which is why most FBO's won't sell it to people any more. It isn't that you will get in trouble it is that they will get into trouble. If you buy it from them you are asking them to put themselfs in jeapordy. So if you do it is best for them you don't tell anyone.
As far as fuels in general, most stations are or have changed from winter blends to summer blends or mixtures in between. In doing so, if you have a high compression highly cammed engine you may need to adjust your jets every time they change fuel. On top of that I have heard (not known for sure) that they can now put alcohol in fuel without telling you now. Worth finding out.
Gary
You are not paying road tax with this fuel which is why most FBO's won't sell it to people any more. It isn't that you will get in trouble it is that they will get into trouble. If you buy it from them you are asking them to put themselfs in jeapordy. So if you do it is best for them you don't tell anyone.
As far as fuels in general, most stations are or have changed from winter blends to summer blends or mixtures in between. In doing so, if you have a high compression highly cammed engine you may need to adjust your jets every time they change fuel. On top of that I have heard (not known for sure) that they can now put alcohol in fuel without telling you now. Worth finding out.
Gary
Hi George,
I did not take it as a rebuttle by any means, in fact it was an informative post, keep those coming! I just wanted to point out that he is a 76 sales man, so his info although correct, will be biased. Kinda like asking a Coca Cola rep if Pepsi is better.
Thanks again, Ron
I did not take it as a rebuttle by any means, in fact it was an informative post, keep those coming! I just wanted to point out that he is a 76 sales man, so his info although correct, will be biased. Kinda like asking a Coca Cola rep if Pepsi is better.
Thanks again, Ron
I believe that it was Hot Rod magazine that did an article on mixing auto pump gas and leaded gas.
I don't think that I saved it. It had to do with mixing unleaded premium with leaded gas of 1 gram, 2 gram or three gram per gallons.
Where I am located in NY, Westchester County, forget about buying any kind of leaded fuel besides Sunoco Leaded Cam II from a dealer.
I can't even get 50 gallon drums delivered here anymore because a truck carrying the fuel is not permited to cross the George Washington bridge (legally).
Some of my friends on the New Jersey side of the Hudson River may not have this problem. Of course gas is also $.30 a gallon cheaper there but who's counting?
...and to answer others questions generally speaking in the NY Metro area one needs to avoid crossing bridges with any kind of a "valuable" high performance vehicle if at all possible with the Throggs Neck as one of the possible exceptions.
Secondly, about 1978, the Westcheste County Airport forbid the sale of Avi gas for anything other then aircraft.
At that time it was muy understanding (the officer didn't draw his weapon and hold it to my temple but his hand was on the handle) that this was illegal and a class A misdomeanor. (1 year in jail).
I was informed by my Boss 429 friend that worked there that leaded fuels were no longer available at the airport for aircraft.
Since I no longer run higher then 10.5:1 cr in any of my cars, the octane issue has gone away for me. Ordinary pump Premium runs fine.
There was also discussion about regular unleaded fuel burning hotter and making more HP then premium and being cleaner the premium on emissions testing.
I don't think that I saved it. It had to do with mixing unleaded premium with leaded gas of 1 gram, 2 gram or three gram per gallons.
Where I am located in NY, Westchester County, forget about buying any kind of leaded fuel besides Sunoco Leaded Cam II from a dealer.
I can't even get 50 gallon drums delivered here anymore because a truck carrying the fuel is not permited to cross the George Washington bridge (legally).
Some of my friends on the New Jersey side of the Hudson River may not have this problem. Of course gas is also $.30 a gallon cheaper there but who's counting?
...and to answer others questions generally speaking in the NY Metro area one needs to avoid crossing bridges with any kind of a "valuable" high performance vehicle if at all possible with the Throggs Neck as one of the possible exceptions.
Secondly, about 1978, the Westcheste County Airport forbid the sale of Avi gas for anything other then aircraft.
At that time it was muy understanding (the officer didn't draw his weapon and hold it to my temple but his hand was on the handle) that this was illegal and a class A misdomeanor. (1 year in jail).
I was informed by my Boss 429 friend that worked there that leaded fuels were no longer available at the airport for aircraft.
Since I no longer run higher then 10.5:1 cr in any of my cars, the octane issue has gone away for me. Ordinary pump Premium runs fine.
There was also discussion about regular unleaded fuel burning hotter and making more HP then premium and being cleaner the premium on emissions testing.
quote:Originally posted by PanteraDoug:
I was informed by my Boss 429 friend that worked there that leaded fuels were no longer available at the airport for aircraft.
Uhm, 100ll (low lead) is pretty much universal.
It may be a missdemeanor for you but the FBO's are the ones putting their neck out. They have a lot more to loose.
Yup, something like that Comp2. Pitty.
I have found the FAA and many government agencies to be a funny group. They put the "good guys" under the magnifying glass and turn a blind eye to the bad guys. I have seen aircraft accidents where they never visit the FBO the accident aircraft just left for fear of mounds of paper work and violations that would never end. They spend all their time at the good FBO's where people cross their "t's" and dot their "I's". They come in and threaten a fine if this "I" doesn't have a dot on it yet the operator next door is running illegal charters, airplanes are non complient with maintenance, etc...They won't even step foot in that door.
The crap they come up with is never ending. A few years ago the guy washing the airplanes saw a suspicious guy in the corner of the hanger. He acted like he did not see him, walked to the adjacent hanger and grabbed the boss. The two of them confronted the guy. Turns out it was an FAA inspector checking "Employee reaction" to this behavior. He was not happy with the fact that the airplane washer did not confront the guy himself and instead left (for backup). They were fined for $10k. They paid the fine, the FAA guy left "Duty here is done!" and that was the end of it. The airplane washer did not get into trouble and was told he did the right thing. It did not change anything. To fight it means more inspections, more fines.
It isn't just this way with the FAA. It is with many if not most government agencies. This is why I pointed out that when you put the FBO on the spot like that, a line guy may be doing you a favor, but you put the burdon of risk on the business and it's not fair to them. They have enough to deal with when they operate on the up and up. It isn't just county regulations they are dealing with either.
Gary
The crap they come up with is never ending. A few years ago the guy washing the airplanes saw a suspicious guy in the corner of the hanger. He acted like he did not see him, walked to the adjacent hanger and grabbed the boss. The two of them confronted the guy. Turns out it was an FAA inspector checking "Employee reaction" to this behavior. He was not happy with the fact that the airplane washer did not confront the guy himself and instead left (for backup). They were fined for $10k. They paid the fine, the FAA guy left "Duty here is done!" and that was the end of it. The airplane washer did not get into trouble and was told he did the right thing. It did not change anything. To fight it means more inspections, more fines.
It isn't just this way with the FAA. It is with many if not most government agencies. This is why I pointed out that when you put the FBO on the spot like that, a line guy may be doing you a favor, but you put the burdon of risk on the business and it's not fair to them. They have enough to deal with when they operate on the up and up. It isn't just county regulations they are dealing with either.
Gary
Im sad for the troubles they cause but glad that I didn't get involved in flying, although a Huey with a slick hanging out the door under the proper conditions could be attractive.