Is it better for a T to run 100 low lead than the 10% ethanol blend?
Our office backs up to the Olive Branch airport so the fuel is easy to get.
Other than the T smelling like Cessna, as well as the additional expense, would it be better?
When the engine was rebuilt, I believe that hardened stainless seats were installed.
Even if your T was built in 1927 it probably never saw any lead in its gas for the first 10 years of it life. I am told that no Ford motor prior to 1931 needs lead. I have little experience with ethanol blends as they are not used much in my country. However here lead containing gas is only able to be used on the race track due to environmental concerns -Karl
The Model T engine was designed to run on the notoriously poor fuels of the day. Octane levels in the twenties were routinely 40-60. I know our local airport offers both: 80 octane and 100 octane. a 4:1 compression ratio (or even a 6:1 with a Z Head)hardly needs 100 octane to be happy. Lots of guys I know run E-10 without complaints, and some others hate it. At what AV gas costs, I would just look around and see if you can find regular no ethanol fuels. Some farm co-ops up here carry them. And last I looked, even no-alcohol premium at the pump costs less than 80 AV gas.
Bill, If you are looking for a place that sells non-ethanol fuels, check out this website:
Then if you type in the station's name and location of www.gasbuddy.com you should be able to compare prices.
Bill the biggest problem with the !0% ethanol is that ethanol is hygroscopic (fancy term meaning it readily bonds with water and if you let the gas stay in your tank for long periods water will collect in the bottom of your tank and or Carb. causing corrosion a good tank sealer and running your carb dry before storage solves most of these problems. If you do store fuel in your tank for more than 60 days be sure to empty sediment bowl and drain a couple of ounces before your first start.
As long as your car doesn't have a cork float and is otherwise stock and you drive it fairly regularly, I don't believe you will ever have a problem with E-10. I ran my TT on E-85 for a year with no problems, other than hard starting in the dead of Winter. A stock T has no rubber components in the fuel system to be affected by the ethanol. The horror stories of attracting moisture are hype in my opinion. Any moisture that gets into the system is absorbed into the ethanol and goes right through the engine with it, just like it does when people add a can of Heet to the system to keep their fuel lines from freezing up.
What I am much more concerned about is the ethanol in my wife's '67 Mustang. We used to have a station that had all ethanol free gas. Then they went to a single pump with ethanol free 87 octane. The Mustang needs 93. So it's either ethanol or pinging like nobody's business, or retard the timing until it don't. Hell with that. I looked at octane boosters, but none convinced me they would really boost the octane. At least they didn't say how much. "Add one can to up to 21 gallons" doesn't sound too scientific to me. The latest thing is ethanol treatment. We'll see how that goes. Hope it works, or at least I hope the fuel pump diaphragm goes before the rubber fuel line blows fuel all over a hot manifold.
A stock Model T? I wouldn't (And I don't) worry about ethanol.
From what I understand about water collecting in the tank. Water may be put in with contaminated fuel. Water that is condensed from the air is relative to the amount of air in the tank and the relative humidity of the air that has entered. If the air has entered contains 10 or 20 % humidity it doesn't get any greater it doesn't matter how long it sits. If you empty your tank on a low humidity day the tank will stay that way, high humidity a different story but it will not get any greater no matter how long it sits.
There's nothing about 100 Low-Lead aviation gasoline that's low-lead. The reason they call it "Low-Lead" is that it contains less lead than 100/130 octane aviation gasoline which is the stuff they used to burn in monster radial engines like those on Lockheed Constellation prop-liners.
100LL has more than enough lead in it to foul your spark plugs and crust up your valves, and it absolutely will do so because Model T engines don't generate nearly enough heat to vaporize the lead.
100LL has so darn much lead in it, I used to have to add a hefty dose of tricresyl phosphate (a lead scavenger) to my '47 Navion's fuel tanks and that airplane had a 470 cubic-inch engine that would run cylinder head temps in excess of 480F.
Believe it or not, you're way better off running today's cheap, alcohol-infused automobile gas than 100LL avgas in your Model T.
I don't know if my car knows the difference between white gas, paint thinner or gas at the pump...they all run just fine. Hell I've even use Kerosine once, had to readjust the carburetor mixture knob a wee bit, but it ran on it just fine.
As long as your T is fairly stock and not got any of those extravagant or exotic metals in it (magnesium, aluminum or titanium) it should be ok.
One big advantage to 100 LL is that it has a long storage life. Airplanes sit in hangars, on ramps unused much more than they fly. When 100LL evaporates it does not turn to corrosive muck like any of the typical automotive spec gasoline.
You won't notice any difference in the way your T runs on 87 octane unleaded compared to 100LL.
I don't take any chances. The place where I work has alot of old equipment that is not ethanol friendly, so we have always ordered regular, non-ethanol gas for our fuel depot, which means I have always used regular in my '26 Model T coupe and it has never complained. Jim Patrick
I used 100 LL in a Corvair during the 1979 gas crisis, and burnt the valves. The 165 Franklin in my Bellanca fouled the plugs after burning less than 40 gallons of that crap.
Long storage life is the only advantage of avfuel in a car.
Many years ago, I tried 100LL in a motorcycle I took to the drag strip. It seized the carburetor and I had to walk it back to the pits.
Olive Branch?? Mississippi?? I'm in Memphis!
"I used 100 LL in a Corvair during the 1979 gas crisis, and burnt the valves."
It may well be possible that the lead first solidified on the stem making them stick partially open thereby burning them. The fouling in the old airplane engines were usually the low compression models.
Royce does make a point on long shelf life. In an engine that runs near its peak all the time the 100LL works great. It may still foul a plug which is why so many run TCP with it.
I can attest to running it with no ill effects in my lawnmower and a generator. Both of those examples run wide open all the time. That gas is still good after 2 years.
I would not run it however in my T.
I've used thousands of gallons of 100 LL in automobiles that have 400 or more horsepower. 100LL is equivalent, octane wise, to about 102 in automotive octane rating terms. There is no way you could blame burnt valves on using 100 LL in a Corvair. There is nothing in 100LL that could or would cause a motorcycle carburetor to seize.
I agree with you Royce. I was only offering up to RD that the root cause for his valves burning might be something other than the octane of 100LL. I replaced a cylinder this summer that was installed new about a year prior to that due to a leaking exhaust valve that was burning the edge all the way around. It wasn't seating completely. It was still showing 62/80 but the other five were all 79/80. Since it was under warrantee I pulled it and sent it back. Its fine now.
What I was trying to illustrate was his Corvair doesn't run full bore developing heat and if the valve to guide clearance was tight he may have caused the hang up with the high lead content. If his exhaust valves were off the seat for any reason they would burn. The burning is caused by leakage and not the 100LL.
I wasn't blaming the octane, but the lead. Indeed, it may not have been 100 Lotsa' Lead, but 100/130.
You are correct, the lead is what causes the valve to stick. Once its held off the seat it will burn. Continental issued a SB years ago that addressed it.
@ Hal Davis
"What I am much more concerned about is the ethanol in my wife's '67 Mustang. We used to have a station that had all ethanol free gas. Then they went to a single pump with ethanol free 87 octane. The Mustang needs 93."
What kind of 67' Mustang do you have? I was under the impression that 87 octane is fine for most stock Mustangs. If you've got a higher compression engine in it, then you might need a higher octane.
Just wondering. My 67 is the 6 cyl. so regular unleaded has been fine for me.
My wife's '67 Mustang has the 289 cid V-8, but only the 2 bbl carb, not the 4 bbl. With the timing set at spec, it will ping on 87 and 89 octane. It runs well on 93. I'm sure I could retard the timing until it quit pinging, but who wants to do that?
My younger brother was a technician for Honda in the 1970's, Japan had by then lead free gas and tighter specs for what they built, leaded fuel played havoc with the valves and carby slides back then.
OK, I'll bite. What's a carby slide? I know what a carby is, but not a carby slide. I would guess intake manifold, but I can't imagine how unleaded would hurt a manifold, so I'm still wondering.
Hal the slide in motorcycles sorta does the same function as the butterfly in an auto carb. as the slide travels upward it drags the needle up with it and allows more air/fuel mixture because of the close tolerances on the slide (think of it as a piston with no rings any lead fouling around the slide would cause it to seize which is why motorcycles went to a push - pull cable system so you were positively moving the slide.
I gotcha. Like a Mikuni. I was thinking Honda cars, not bikes.