Bill Goddard
Well-known member
Can you use 100 octane Avgas in a model A? Bill G
AvGas in the ford
- Thread starter Bill Goddard
- Start date
Railcarmover
BANNED
Just be careful.its a slippery slope..the next thing you know your building a car for the salt...so broke the kids are eating the putty out the windows,racing broke..
Synchro909
Well-known member
You don't need the octane avgas has but for you guys, at least it doesn't contain ethanol.
Pete
BANNED
A true racer spends everything he makes on racing, minus 10% to live on....
Keith True
Well-known member
I just don't know why you would need 100 octane gas for a car that was built when 67 octane was the good stuff.One company was so proud of their high octane gas they named their stations after it,Phillips 66.Some used to get it at an airport about 15 miles from me,but they got caught on the road tax thing.Now they will sell it to you if you bring a can,and tell them it's for your lawn mower.
Railcarmover
BANNED
Their innovation drives the whole hobby..I just don't have what it takes to build it then break it.Big difference between 'if' and 'when'..a street guy fixes it if it breaks,a racer when it breaks.
Legend has it that Frank Philips named the company for Route 66, the most-traveled highway in the US, although the headquarters was in Bartlesville, on Route 60. Guess he figured 66 was faster.
The refinery on the south side of the highway really stunk up the place, i remember.
Keith True
Well-known member
There is also a story about it being named Phillips 66 because it was the 66th attempt at a formulation.I had read the naming after the octane in an article by the Conoco oil company about the progress of gas refining over the years.Werner,lead was not in widespread use at the time of the A either.I won't say it was non-existent,because it was being experimented with.I have the first gas pump that dispensed leaded gas in my town.It was right after the war,and the store owner told me that his first load of leaded gas went sour before he could sell it all.The old folks didn't like change then either.Some had the idea there was metal in their gas.The only plus I see to it is that it does keep very well.
Purdy Swoft
Well-known member
One hundred octane gas was available at most filling stations up until around 1970 and shortly after . The octane was posted on the pumps . Ethyl gas or premium as we called it was usually one hundred octane or more . Regular gas was usually 94 octane . I always used ethyl gas in everything that I run including the lawn mower. Higher octane gives a bit more power . If hundred octane gas was still locally available at a reasonable price , I would still use it .
juanvaldez
Junior Member
The octane rating system has changed since the old days. The new method R + M / 2 averages research and motor octane and give a lower number. I think modern 93 is really around 100 by the old method. Modern avgas, 100 LL is really around 93 octane by modern method. As for lead, 100 LL has about four times (2 grams/gallon) the lead as the old eythl and really fouls plugs.
rotorwrench
Well-known member
A person used to be able to purchase 80/87 for lower compression engines but those days are long gone. 100LL is one of the most stable fuels there is obviously due to it's intended purpose. It is called low lead but it still has more TEL than any normal auto fuel. I've had trouble with lead fouling on 10:1 compression aircraft engines so a person should expect some on low compression engines. It will work but it's overkill on most antique engines with low compression. The price is high and it's a PITA to buy. You won't find it an the local stop & rob.
Purdy Swoft
Well-known member
The lead in the older high octane gas at the pump reduced timing knock . With leaded gas timing could be set more advance and have no knocks , with more power . Gulf use to sell gas they called NONOX . My spelling may not be exactly like Gulf spelled it but close .
That's a new one on me! I have read many accounts stating that Philips 66 was so named because they were so proud of selling gas with 66 octane.
Rotorwrench, Now you've got me curious. What little I know about aircraft engines has led me to believe that 10 to 1 was way too much compression for an engine running under constant heavy load (wide open or nearly wide open), especially air cooled and/or super/turbocharged. Are you referring to aero-race engines like in the Reno Air Races? Thanks!
Floats
Well-known member
40 Deluxe,
Aero engines do not run ‘under constant heavy load’. Most aero engines have a maximum speed of about 2700 rpm and climb rpm @2500 and around 2400 to 2450 at cruise.
Aircraft engine speed is limited to propeller speed which becomes inefficient at higher speeds. At higher engine speeds, a reduction gearbox is required to maintain a prop speed of around 2000 rpm, depending on the propellor design.
Dakota engines and props turn at around 1800rpm in the cruise.
Your observation of ‘constant heavy load’ is mostly prop noise related and not engine loads.
Regards
Chris
Aero engines do not run ‘under constant heavy load’. Most aero engines have a maximum speed of about 2700 rpm and climb rpm @2500 and around 2400 to 2450 at cruise.
Aircraft engine speed is limited to propeller speed which becomes inefficient at higher speeds. At higher engine speeds, a reduction gearbox is required to maintain a prop speed of around 2000 rpm, depending on the propellor design.
Dakota engines and props turn at around 1800rpm in the cruise.
Your observation of ‘constant heavy load’ is mostly prop noise related and not engine loads.
Regards
Chris