Mpgp1999

Avgas in a Dodge

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I have access to 100ll leaded gasoline for my dodge. Besides that it costs less then premium gasoline. It cost 4.75 San Francisco Bay Area. Is there any benefits in regards with storage and lubricity. 

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A friend of mine back in HS used to put that stuff in his 69 Chevelle SS 396.  Of course that was an 11:1 cr "built" engine that really benefited from it.
AFAIK (and I'm far from an expert) the only benefit you'd get would be the lead providing valve seat cushioning.  Oh, probably also the benefit of having no ethanol added but you can also get that benefit by carefully choosing your filling station (at least in PA you can).
The high octane rating will be totally lost on your engine since it has such a low cr.  Kind of like giving a wino a $1000 bottle of wine.  Pointless...
And there's also the fact that avgas doesn't have a road tax applied so getting caught doing what you're thinking about would probably get you a big fine.  Same as the risk the lifted diesel 4x4 truck guys take when they put dyed home heating oil in their trucks.  Cheaper fuel until you get busted.  Then expensive fuel.
Just my .02

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What year Dodge? Many 6-volt cars have trouble lighting high-octane gas and often don't run as well as they do with the cheap stuff. For example, the owner's manual for my 1941 Buick says to use 72 octane for best results. Even my 1993 Mustang 5.0 runs noticeably better on 89 than on 93. High-octane can be tough to light with those 6-volt electrical systems and low-compression engines. Avoiding ethanol is often good, but I don't really think avgas is a solution unless you're just going to use it for storage purposes and even then you might have trouble with it running correctly and if you're using avgas, you won't blame the gas. It can introduce a whole different set of variables to your engine if and when it starts to act up. As long as you keep the fuel moving through the car on a regular basis, I don't see much harm in regular unleaded in old cars. I have 110 old cars sitting here at any given moment and they've all got pump gas in them, nothing special. They all typically start and run, and if they don't, the most common issue is a stuck float which is easy enough to cure. Don't bother with premium, either--there's nothing in premium that's not in regular beyond a higher octane rating. It doesn't make more power, it doesn't clean the engine, and it isn't a special treat for the engine now and then. If your compression is less than 10:1, you probably don't need it.

 

Avgas is an expensive solution to a problem that isn't really a problem.

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May want to check local marina . Some have non-ethanol in pump with lower octane .   

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Higher octane fuel burns more slowly than lower octane fuel. You will find the exhaust side of the engine gets quite a bit hotter - it is may even be still burning as it goes into the exhaust. You may even have valve trouble.

 

Your car was made for, what, 53 octane? Or maybe 63 octane? Use the lowest octane you can find.

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There are a number of restoration shops and museum collections using Avgas in their restorations because it will not evaporate like all the modern ethanol.  Maintains its characteristics for up to two years compared to pump gas beginning to deteriorate after 2 weeks.    And some auto repair shops will use it too - a local shop told me he does and explained how to get it at the airport.   The antique guys find no problem whatsoever in their low compression early engines.

 

It is indeed 100LL today meaning "low lead"  and there is minimum benefit from there being this little lead... but some.   Years ago, Avgas had much more lead - no more.   Under US law, you can not run Avgas on the street because it does not include your state or federal road taxes.   Avgas burns very clean, it is very pure, your car will start every time, your carburetor will love it,  it will not destroy any rubber hoses or diaphrams or carb parts.     100LL is rated as 100 octane "at altitude" so in reality it is somewhere around 95 octane at your ground level, depending on where you live. 

 

Fair amount of bother for me to get into my small regional airport and buy 100LL (credit card at their pump, must bring container, must enter the tail number of a prop plane) and they have gates.   But I do it when I need to and find it totally worthwhile and have never experienced any down side.

 

Try it.   I think you will really like it.

 

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My car is original 12v. Made December of 25. As for the octane I have heard of people using kerosene 1:4 or diesel. 

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Posted (edited)

I recently rebuilt my vacuum tank and now the fuel evaporated from the carb and vacuum tank in a day or so. In the past I have gone a month or two and there would still be some gas in the vacuum tank. The connections are tight and I see no signs of leaking fuel. 

Thats why I have a can of fuel to prime the carb. That extra fuel is avgas. The tank currently has 91 maybe with some marvel mystery oil. Since I am next to an airport I just walk over there with a jerry can and fill it at 4.75. For 100ll

Edited by Mpgp1999 (see edit history)
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Posted (edited)

For the issue of road taxes. Couldn’t I keep track of the non taxed fuel that I used and pay the taxes at the end of the year. Is there any lawyers out there? I don’t see kerosene for sale with road taxes 

 

avgas is taxed federally and by california. I should not have any legal issues when using it on the road  To my knowledge clear kerosene is taxed and dyed is not. 

Edited by Mpgp1999 (see edit history)
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8 hours ago, Mpgp1999 said:

For the issue of road taxes.

 

You are paying the road tax every time you mow the lawn or go for a boat ride.

Kinds offsets itself.

If and when I winterize I use 120 leaded race gas. Easy to find in most areas, just not at a gas station or airport.

As for evaporation, I keep one of those metal squirt cans full of gasoline with pressure over it. VERY handy.

 

https://www.ebay.com/itm/Liberty-Spot-Sprayer-Pressurized-Spray-Can-Steel-Red-1-qt-32oz/123815854893?hash=item1cd400032d&_trkparms=ispr%3D1&enc=AQAEAAADIKvsXIZtBqdkfsZsMtzFbFsbX3WcW5fmB%2Fx7ZbaZTyex5%2F5IBesqWURBxPsBx%2FTFyfde0VhS1ArmaoJQ8B9Vg%2FUHdH3sHIhYEGGgXkgTGo%2Baw3uMO%2FvjCvMy1ETzZLjVRft70Eoq4ejzEpAuuHH4Aozldfjks4h%2B7i5tqi3xHR4pjz%2FSO607oaL2zbPIL2MvMWe3erAWaM0LG6D39QxisTEY%2BwaWjzzIekHQo%2F88e4uVrAKbP0kkAwojmCMho%2B4JXYCWq%2BRws8E18ZszPKh43I1f%2BE1JIButODq6ny0n86FqsqUWlZOeYezq%2F2zzb5fBJnCHjY8ghAihLIt3XinAa9lCUpqXlqdtxVZsrkJXIWT5BOJmLaOi19vGQylYyWBwrTNNvQjC0h7o%2FoQ8iAhpFlvVogi9%2BySDm3OrUeim3J0%2BzFu8MbdBvxCIzWjoQDZDG2GDgTjb8dvOQTTIbIE2rbbwoWd5v3PFjWJ268oUwUfMxLzCkk8I%2B01n0qP5WzNYzW6JUmHwr5apL9Bi26e1HhXp9aWEw1vTMGAx4t%2BOV3ynqxu8bA3LGPo19ejIoq1xK%2BW9CB4mWW60G5nSsYg0uRxtg6iLxyNJdgZUEtf40%2B3rIrLRRtqFexxxNnIdfRRljv3UKbnfMDqzLOooA6H5u%2BnE3aMgJLyM7m07Dc9f1Gg%2FQ8gK0KUEFwfzyQ5jowLBX0XH5r9BvOKFaR8DD7KwUSbJNuXewUmIYlx6cGkwJWQ3Ery2DJj6Gi5scpVXIHB6HJ4BcbuKfk9n3qZr5zE6B4Ya5D%2FTJhmsh38HrVfrgBIvH3OJuGQdE8H%2BgNsba0GoqqlRisA7cfqqSqdF9Ym6%2B6HiVkO37JpwhVzndU6leRAkTq1OSFRyrUdqk80i1C8pw%2F8xuirpR9Q%2B1qv0jjd%2FMwO97xGbR0peY7nXFSO4e%2BBMl6JNw7bUfjg7m6l%2FD58tLRvZ153NHaXJX%2B5bZFV9OhO7Qa4wvkut4CJarJsKK3ejCE%2FQ%2BbytrNPtyoHFalocneejSv29ErYTOQBmtk2jFcZZvWbi%2FusLQ9iAUjUELk1g&checksum=1238158548932bcd69a8963b4c63b370390662f4be8b

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WOW !! that is one long link address.

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Many taxpayers may be overlooking the refund or credit available under IRC § 6421 for federal excise taxes paid for motor fuels and similar state provisions. The taxes are on fuels used to power vehicles and equipment on roads and highways. Taxes paid for fuel to power vehicles and equipment used off-road may qualify for the refund or credit. This includes farm equipment and certain boats, trains and airplanes.

 

https://www.journalofaccountancy.com/issues/2011/mar/20103438.html

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23 hours ago, Spinneyhill said:

Higher octane fuel burns more slowly than lower octane fuel. You will find the exhaust side of the engine gets quite a bit hotter - it is may even be still burning as it goes into the exhaust. You may even have valve trouble.

 

Your car was made for, what, 53 octane? Or maybe 63 octane? Use the lowest octane you can find.

 

Flame front propagation rate is a good analogy for the process. But it is not precisely accurate. 

 

Octane in the mid-'20s was in the mid 40s. 

 

I have a very important medical appointment. Must run. In the meantime, I will just reach into the grab bag and throw a little pulp at the wall. If it sticks, browse it in my absence. I need to establish my credibility before I distill this down. I spend quite some time on this issue.    -    Carl 

 

 

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58 minutes ago, C Carl said:

 

Flame front propagation rate is a good analogy for the process. But it is not precisely accurate. 

 

Octane in the mid-'20s was in the mid 40s. 

 

I have a very important medical appointment. Must run. In the meantime, I will just reach into the grab bag and throw a little pulp at the wall. If it sticks, browse it in my absence. I need to establish my credibility before I distill this down. I spend quite some time on this issue.    -    Carl 

 

 

E91014E0-BFBA-4374-AA1B-A17CE2385F78.jpeg

DE614314-F4B0-4570-BC60-013F9CD27AA2.jpeg

E0B4800F-42FD-4BF7-AA40-D2327A67ACE6.jpeg

4D6CB667-FC18-4846-8BFF-ED653B20D0B7.jpeg

This is very interesting. What is this book. 

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 A spare moment which gives an opportunity to the benefit of all. I will be back to clarify, but no matter what your background may be, you will derive something from all of this. Perhaps some of you could have written this, to others it is quite new. Most of us, myself included, will find ourselves somewhere in between. More :

 

 

 

 

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Sure. The first book is : "Marks' Mechanical Engineers Handbook, 2nd edition, 1924". 

The first book of my second posting is : "Marks', 3rd edition, 1930".

All the rest come from a couple of the annual editions of : "Merck Index" from the late '50s, and the '60s.

 

For you, Mathew, I would recommend "Matks', 3rd". Fascinating read to understand aspects of the sophistication of engineering of the period. I am sure you know how to shop far better than I. Please let me know what these are selling for now. A "Merck Index" should be relatively inexpensive. I used to pick them up from University of Washington surplus. Could run from 50 cents to a buck or so. Let me see if I can find a page from the period I have referenced, which may be very automotive. Please standby.   -  Cadillac Carl 

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Octane in the 20s about 45octane? Ron mon or Ron+mon/2. What issues can occur with high octane in a low compression engine. My motor is about 50-55 psi. 

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I was able to find the 2nd edition online for under 35 with shipping. 

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As far as the lead goes, I think it's safe to say that the Dodge engines from 1914 through 1925 (at least) were not designed with the assumption that leaded fuel would help lubricate the valve contact surfaces.  Leaded fuel wasn't introduced until the early 20's although I can't seem to dig up a more specific date.  As for ethanol in fuel, my '25 seems to run fine on it (summer blend 87 octane) and I've never had any vapor lock problems on hot days in traffic (granted CT isn't the best climate to test this).  I also find that if I don't start the engine for 2 - 3 weeks, there is still enough fuel remaining in vacuum tank to start the car (I do shut the valve at vacuum tank fuel outlet between uses).  On the other hand, I've never driven the car with ethanol-free gas for comparison.

Edited by MikeC5 (see edit history)

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