Who said were too old too learn,high test and low octane fuel characteristics,that is one i never new before today.Its going down near zero tonight, getting close too peek winter anyway,that should help.
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Thank you Chris I saw several people read my post and liked it but no one was taking me serious and answering my question. So if most of us still have the knock sensor ( pezio crystal) then possibly we arenāt needing the manual distributor advance as much.
Up here all you can get without ethanol is premium. I use it in everything that I donāt run on a regular bases so when I do want to run something it is not all gummed up. It was costing me a small fortune to mow my lawn. Always use the premium in that because we never know when the first snow will fall and the mower goes in the barn for the stay.
Again thank you. TomC
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most of what I have come across tom the computer does the advancing the knock says stop that hurts.
and I also make special gas runs for all the yard equipment I have replaced too many fuel lines and carb cleanings drive one nuts. soo glad to see 87 no ethanol here only one place so far .
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So then the question comes down to how do we change the sensors that ARE guiding the spark to just the knock sensor so we can get the timing going until the knock sensor says "uncle"TomC.
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Hey Tom forever how much you know sports think of it this way.
Each modifing trimming sensor like the O2, Baro, Map, knock are like the line judges. They have to work within the rule book written into the look-up tables in the processor.
So the best way would be to rewrite that rule book. This is what the chip swappers used to do. What EEPROM reprogramming does. Even what some of the hot-rod (āfor racing off road use only!ā) add on filter boxes do.
Or . ā¦
Go buy off that line judge to look the other way. Turn a blind eye. Out right lie on his report. This is the sensor emulating/spoofing approach.
Heck of a lot easier to do this on a factory āflex-fuelā vehicle looking for an alcohol % in the fuel and having much wider possible ranges look-up tables built in alreadyā¦
These systems began in the mid-90ās.
Regards
Steve Unruh
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Hi Steve; Glad to hear from you. I was afraid when you close your thread you were deserting us.
Iāve set here for over an hour trying to make a case for more use of the knock sensor but in the end Iāve decided the present computer tables are probably fine. Even though we have changed the rules of the game by going from petro to woodgas. We are going from a lower octane fuel to a higher octane fuel. That means the woodgas will allow more advance before knocking occurs, but by that time other sensors such a manifold pressure, engine RPM, throttle position have maxed and prevent more advance. Thus never getting to where the knock sensor plays a part.
Dam, I hate it when my second thought catches up with my first thought and I find I have been wrong.TomC
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Tom I think for us GM guys a good start would be to figure out how to bypass the overdrive retard. Did you ever do a gear change? I have 4.10 gears and a big block so I hope I can use overdrive, time will tell.
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Iām still thinking on it Jim I am puttering with little projects because with the weather my time in the shop is very limited. Maybe as spring gets closer, But then right away we have Argos come up and afraid I wonāt get it done before that.
I had 410 gears in a smb with a regular automotive automatic transmission and on the LA freeway it was wound up to tight so I went to a 373. I think a 410 with an overdrive will work. TomC
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No Tom youāre OK doning this. Think thrice before you cut commit and have a hellavaā back-up patch job top do.
I am tryibg ti type less.
Having much dififulty now with that. Can no longer brain process/see and edit my mistakes.
One missing letter above turned my inteneded ranges to rages. Could hurt social feelings my bad mis-typing now.
egards
Steve Unruh
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Hey guys Iām sure you wonāt be as happy as I, but I remembered what the other question was the other day when I had brain fade
Question about SECONDARY BURN. I have made charcoal with a TLUD 55 gal drum. I put two pieces of rebar on the drum and sat a hollow drum on top to increase SECONDARY BURN. So I have seen it, and done it, but I donāt understand it. So maybe to avoid long dissertations on theory Iāll get right to the question.
I have an old used double 55 gal drum wood furnace / burner. I am thinking about rebuilding it with new barrels. You know how one barrel sits on top of the other and the two are connected with a short piece of 6" stove pipe. If I put holes in the 6" pipe can I get a secondary burn in the top barrel?. TomC
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Tom, the bottom barrel might have too much air. But maybeā¦
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So you are saying this only works with incomplete combustion? If I see smoke coming out of the chimney does that mean I have incomplete combustion. If I add holes in the connecting tube will it ignite automatically from the lower burn or do I have to add ignition to the secondary air? Sorry, but I just havenāt gotten my mind wrapped around secondary burning.TomC
PS Also having trouble with ārocket furnacesā not ārocket stovesā Later subject.
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I aināt no expert. But your smoke needs to be strong enough to burn. One way to think about it is stages combustion. So the first stage needs to make a self burnable smoke. Iāve made thingies that made weak gas that only would stay lit by using another flame or glowing char.
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The octane rating of the fuel does not alter the energy content of the fuel.
Subtract the ethanol content and they are identical.
How the fuel behaves is a different question
Some engines will run better on a lower octane fuel and produce more power.
Its really hard to pin down exactly why but its got something to do with the lower compression and the fuels resistance to ignition ( ping or otherwise ) and flame speed.
One engine I built was actually slower on 100LL.
It needed the octane but the flame speed of 100LL a fuel designed for slow turning aircraft.
With fixed timing there were times when the piston was outrunning the flame front at high rpm.
Blending helped but in the end I resorted to simply adding Xylene to 91 octane until I found a mix that was just right.
In all cases however its the way the fuel burns in the engine that makes the difference in fuel economy when the alcohols are removed from the equation and not the BTU content thatās for all practical purposes identical.
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Uhg, toddler was nice enough to turn the thermostat all the way down on the coldest nightā¦ A good house only goes so far.
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Tom, not what your interested in but a stove I tripped over a few days ago on YouTube.
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Thank you Jeff
This build is still very confusing to me. They put in a smaller burn chamber and then they insulated all around it, I presume to keep the smoke hotter until it gets to the secondary air. And then the chimney is so close to the secondary air that it seems to me the heat would go right up the chimney, with very little contact with the top of the larger barrel.
With the old burn barrel system, you had a larger burn chamber and heat would flow through the walls of the burn chamber. I believe we get a lot closer to complete combustion in the first burn chamber ( for this new way to work you have to hold back on air and create partial combustion in the small barrel ). The second barrel of a two barrel, is just taking heat off the exhaust that would have gone up the chimney.
Thanks again. I am always interested in new ways but my ābullā head gets me to pass on some that I probably should have given a better chance.
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Tom, I think he is storing some heat in the sand and maybe easier on the barrels. He also builds a smaller fire. He also said you can add the second barrel on top. Also two places to cook on.
I gotta go plow snow nowā¦
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Tom, I would call that more of a continued burn as well as a secondary burn. The air in a TLUD comes from the bottom and is limited so that it it creates an oxidation zone that moves farther and farther down the barrel and gets used up in that process so there is not enough oxygen left to burn up the charcoal that remains near the top of the barrel. The unburned products of combustion rise through the glowing charcoal and exit at the top and would rise uncombusted unless the top barrel is there with added oxygen and heat containment which completes the burn and produces no or little smoke.
If you lay that on its side in the case of the barrel stove, the fire will migrate to the loading door and burn everything up as it goes toward the chimney pipe. If you add air holes back there you might not do any more than reduce the draft. I tried that once with mine by opening a one inch bung hole in the back upper barrel that happened to be located right by the 6 inch barrel connecting pipe. I thought I might see some secondary burn there but there was not enough energy left in the smoke to burn again. Thatās my 2 cents worth and maybe thatās all it is worth:grinning:
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