Turbinator Posted July 18, 2020 Share Posted July 18, 2020 Gents, a bit of reading revealed 100 octane low lead ethanol free gasoline is available at small airports. Also, the 100 LL is intended for aircraft use only. The fellow at the local small airport said no worries, for the little you are using for consumption in a vintage car is no problem. Come by 9AM-3PM daily and get what you need. So, for the guys that like higher Octane, low lead, and ethanol free gasoline an airport is another source of supply. Turbinator 1 Link to comment Share on other sites More sharing options...
PWB Posted July 18, 2020 Share Posted July 18, 2020 (edited) Curious as to the cost? Couldn't hurt to do a mix with local 92 Octane? Edited July 18, 2020 by PWB (see edit history) Link to comment Share on other sites More sharing options...
BulldogDriver Posted July 18, 2020 Share Posted July 18, 2020 100 low lead fuel for aircraft is not the same as automotive. The amount of lead is compared to the 130 leaded aviation fuel which to my knowledge is no longer made. Aviation 100 LL has different characteristics than automotive fuels and can burn pistons in automotive use. Do your research first. Ray 1 Link to comment Share on other sites More sharing options...
telriv Posted July 18, 2020 Share Posted July 18, 2020 Ray, NOT IF THE ENGINE IS TUNED PROPERLY & IS MIXED WITH PUMP FUEL. One of the problems is it has a lower boiling point for the altitude. I wouldn't run it straight. Tom T. 1 Link to comment Share on other sites More sharing options...
BulldogDriver Posted July 18, 2020 Share Posted July 18, 2020 Understood, but some wouldn’t know that and is why I said do your homework. I really don't see enough benefit for the extra cost and risk on these old engines. Just my 2 cents. Ray 1 1 Link to comment Share on other sites More sharing options...
Turbinator Posted July 19, 2020 Author Share Posted July 19, 2020 6 hours ago, PWB said: Curious as to the cost? Couldn't hurt to do a mix with local 92 Octane? PWB, I answered before but the response evaporated in cyber space. This will be direct: small airports across the country sell aviation fuel. The fuel I’m referring is known as 100 LL ( low lead) ethanol free. Locally the price ranges from $3.69-$5.50 a gallon for 100LL. I’d do so homework before I’d buy the 100LL and run it straight. 100 LL OCTANE may be too much for some of our engines. I did not know that was the case. I have research to do. Turbinator Link to comment Share on other sites More sharing options...
Turbinator Posted July 19, 2020 Author Share Posted July 19, 2020 3 hours ago, BulldogDriver said: Understood, but some wouldn’t know that and is why I said do your homework. I really don't see enough benefit for the extra cost and risk on these old engines. Just my 2 cents. Ray Ray, many thanks for your heads up and 2 cents worth. Turbinator Link to comment Share on other sites More sharing options...
psychostang Posted July 19, 2020 Share Posted July 19, 2020 (edited) Is that 100 octane using the RM/2, Research, or Motor method. According to my calculations, my 65 Riviera whilch requires either 99 research or 90 motor method, would require 94.25 RM/2 method octane. If I use the 90 RM/2 method octane (non etthanol) and use 2 bottles of Gumout octane booster, I should end up with 93.5 octane. Close enough. Edited July 19, 2020 by psychostang (see edit history) Link to comment Share on other sites More sharing options...
Turbinator Posted July 19, 2020 Author Share Posted July 19, 2020 2 hours ago, psychostang said: Is that 100 octane using the RM/2, Research, or Motor method. According to my calculations, my 65 Riviera whilch requires either 99 research or 90 motor method, would require 94.25 RM/2 method octane. If I use the 90 RM/2 method octane (non etthanol) and use 2 bottles of Gumout octane booster, I should end up with 93.5 octane. Close enough. Psychostang, it is interesting to learn a person could earn a living in fuels and having education in chemistry. Here is what I found regarding octane determination methods. “Aviation gasolines used in piston aircraft engines common in general aviation have a slightly different method of measuring the octane of the fuel. Similar to an AKI, it has two different ratings, although it is referred to only by the lower of the two. One is referred to as the "aviation lean" rating and is the same as the MON of the fuel up to 100.[8] The second is the "aviation rich" rating and corresponds to the octane rating of a test engine under forced induction operation common in high-performance and military piston aircraft. This utilizes a supercharger, and uses a significantly richer fuel/air ratio for improved detonation resistance.[5][unreliable source?] The most commonly used current fuel, 100LL, has an aviation lean rating of 100 octane, and an aviation rich rating of 130.[9]”A very good question was asked regarding benefit of higher than normal motor vehicle gasoline octane in our older engines. In error, I thought a higher 100 LL octane would not cause damage to my engine. After some reading and input from on the forum I believe my best gasoline is one that has no ethanol and up to 91-96 octane. I’m no hot rod type, just having the best fuel in my Riviera is what I’m after. Link to comment Share on other sites More sharing options...
EmTee Posted July 19, 2020 Share Posted July 19, 2020 3 hours ago, psychostang said: According to my calculations, my 65 Riviera whilch requires either 99 research or 90 motor method, would require 94.25 RM/2 method octane. If my memory is correct, 94 octane is precisely what was claimed on the pump around here for Sunoco 240 (Premium). Link to comment Share on other sites More sharing options...
BulldogDriver Posted July 19, 2020 Share Posted July 19, 2020 Aircraft operate under different conditions and power loads. Normal operation is in the upper range of RPM’s and using gauges that give you exhaust gas temps EGT a properly tuned engine would run in a condion known as ‘lean of peak’ which is what our modern engines operate using closed looped oxygen sensors. Something our old motors don’t have. Even with aftermarket EFI, most only sense one side of the motor, one sensor in one exhaust pipe, and still won’t be as efficient as factory systems. I've been flying for 40 years now and have seen many miss informed pilots burn valves, cylinders, heads using procedures from factory Operation manuals and what they were taught by instructors and their fellow pilots. There are 2 books that are readily available online written by one of aviation’s most respected technicians, Mike Busch; Manifesto: A Revolutionary Approach to General Aviation Maintenance and Mike Busch on Airplane Ownership that I strongly suggest as reading. It was always a challenge to get an aviation motor to Time Between Overhaul TBO using factory settings. Using Mikes procedures will get you way past that legally and he explains why. Overhauled one in a Bonanza 30 years ago at $30k and it is still going strong from what I’ve been told. TBO on that engine is 1500 hours. Also every aviation engine gets a visual inspection of the cylinders, compression and spark plugs annually. It is not unusual to have all cylinders, pistons assemblies replaced at 1000 hours, roughly 50k miles in a car. Price that out and a rebuild of our engines is cheap by comparison! Ray Link to comment Share on other sites More sharing options...
Turbinator Posted July 19, 2020 Author Share Posted July 19, 2020 2 hours ago, BulldogDriver said: Aircraft operate under different conditions and power loads. Normal operation is in the upper range of RPM’s and using gauges that give you exhaust gas temps EGT a properly tuned engine would run in a condion known as ‘lean of peak’ which is what our modern engines operate using closed looped oxygen sensors. Something our old motors don’t have. Even with aftermarket EFI, most only sense one side of the motor, one sensor in one exhaust pipe, and still won’t be as efficient as factory systems. I've been flying for 40 years now and have seen many miss informed pilots burn valves, cylinders, heads using procedures from factory Operation manuals and what they were taught by instructors and their fellow pilots. There are 2 books that are readily available online written by one of aviation’s most respected technicians, Mike Busch; Manifesto: A Revolutionary Approach to General Aviation Maintenance and Mike Busch on Airplane Ownership that I strongly suggest as reading. It was always a challenge to get an aviation motor to Time Between Overhaul TBO using factory settings. Using Mikes procedures will get you way past that legally and he explains why. Overhauled one in a Bonanza 30 years ago at $30k and it is still going strong from what I’ve been told. TBO on that engine is 1500 hours. Also every aviation engine gets a visual inspection of the cylinders, compression and spark plugs annually. It is not unusual to have all cylinders, pistons assemblies replaced at 1000 hours, roughly 50k miles in a car. Price that out and a rebuild of our engines is cheap by comparison! Ray Ray, seems as though having a very large boat )(yacht) and or an airplane of any size takes more of an investment in fun than our Rivieras. Turbinator 1 Link to comment Share on other sites More sharing options...
Black River Posted July 21, 2020 Share Posted July 21, 2020 (edited) I've been running 50/50 mix of 100LL and pump non-ethanol 91 octane in my 13.5:1 552 cubic inch iron head Ford for 13 years. Ran the same mix on the nitrous oxide 351 Cleveland that was in it for 15 years before that. Without the 100LL it'll ping itself to death, with it we're good to go. We also ran the same in our drag cars since I was just a little tyke and my Dad drag raced back in the 80s, because there was no such thing as the internet and race gas wasn't readily available. My older brother ran it straight in his 11 second Chevelle..... I've heard plenty of naysayers and have yet to have someone actually give me a reason why not to run it. Usually I get the "because it's dry" excuse, whatever dry fuel means and it seems the people that tell me that can't explain it, either. I ran it in my Riviera, and I run it in both my Cadillacs, I ran it in my 2 stroke race bikes and I still run it in my 2 stroke 200 hp 800 cc snowmobile. And I put the little few ounces left in the bottom of my 5 gallon jugs into my lawn mower, because nothing smells better then "race gas" and fresh cut lawn. I've heard the "theories", but I personally have nearly 30 years experience running it in my cars and other equipment, and many others have even more. It's $4.50/gallon, and that's cheap insurance to me. Edited July 21, 2020 by Black River (see edit history) Link to comment Share on other sites More sharing options...
Turbinator Posted July 21, 2020 Author Share Posted July 21, 2020 2 hours ago, Black River said: I've been running 50/50 mix of 100LL and pump non-ethanol 91 octane in my 13.5:1 552 cubic inch iron head Ford for 13 years. Ran the same mix on the nitrous oxide 351 Cleveland that was in it for 15 years before that. Without the 100LL it'll ping itself to death, with it we're good to go. We also ran the same in our drag cars since I was just a little tyke and my Dad drag raced back in the 80s, because there was no such thing as the internet and race gas wasn't readily available. My older brother ran it straight in his 11 second Chevelle..... I've heard plenty of naysayers and have yet to have someone actually give me a reason why not to run it. Usually I get the "because it's dry" excuse, whatever dry fuel means and it seems the people that tell me that can't explain it, either. I ran it in my Riviera, and I run it in both my Cadillacs, I ran it in my 2 stroke race bikes and I still run it in my 2 stroke 200 hp 800 cc snowmobile. And I put the little few ounces left in the bottom of my 5 gallon jugs into my lawn mower, because nothing smells better then "race gas" and fresh cut lawn. I've heard the "theories", but I personally have nearly 30 years experience running it in my cars and other equipment, and many others have even more. It's $4.50/gallon, and that's cheap insurance to me. Black River, just had my 401 completely rebuilt for reliability and longevity. The engine has 10:1 compression ratio and forged pistons along with balancing, head decked, and engine squared. Just some upgrades and thorough inspection for what the needs would be. I have a hard time in area getting ethanol free gasoline. The little airports are close by and they will sell the 100LL gasoline. One of my knowledgeable zRiviera friends said mix the 100LL with ethanol free pump gas. What I’ll probably do is fetch the 92 ethanol free gas back in 55 gallon drums and be done with it. The ethanol Gasoline was hard on my small engines. Thank you for your input. For a minute I thought I was really off base for wanting to use the 100ll. Turbinator Link to comment Share on other sites More sharing options...
Black River Posted July 21, 2020 Share Posted July 21, 2020 13 minutes ago, Turbinator said: Black River, just had my 401 completely rebuilt for reliability and longevity. The engine has 10:1 compression ratio and forged pistons along with balancing, head decked, and engine squared. Just some upgrades and thorough inspection for what the needs would be. I have a hard time in area getting ethanol free gasoline. The little airports are close by and they will sell the 100LL gasoline. One of my knowledgeable zRiviera friends said mix the 100LL with ethanol free pump gas. What I’ll probably do is fetch the 92 ethanol free gas back in 55 gallon drums and be done with it. The ethanol Gasoline was hard on my small engines. Thank you for your input. For a minute I thought I was really off base for wanting to use the 100ll. Turbinator Nope, not off base, just a lot of misinformation and old wives tales out there about AvGas 100LL. It's all we had back in the day for race engines and before hardened seats became a thing on rebuilds. Like I said, years and years of real world experience running it instead of hearsay with nothing but positive results on anything that is not fuel injected, and the only reason not to run it on those is because it will foul O2 sensors. Link to comment Share on other sites More sharing options...
DannyGarcon Posted July 23, 2020 Share Posted July 23, 2020 It’s a shame I didn’t have my Riviera when I was working at the airport. I was pulling a gallon a day of Avgas doing quality control that could have gone right into my tank. Nothing beats the smell of 100LL exhaust. 2 Link to comment Share on other sites More sharing options...
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