Couldn’t you actually get it to fire on two cylinders reliably. if you used cylinders at position 1 and 5 and the distributor position 1 and 4.
wouldn’t tdc for the ignition stroke look kind of like this for the crankshaft angles?
8cyl 6cyl
0 0
90 120
180 240
270 360
360 480
450 600
540
630
I admit that this is 30 inches of snow in the last week, mental masturbation. It keeps worming it’s way into my brain because I would like a compressor that puts out more than 20 CFM. I had a gas driven one that put out 24 CFM but I burned in up in a fire a ways back and have never had the money to replace it. I have seen videos of VW beetle engines made to run on two cylinders and pump air with two which is kind of what got me to thinking. Not too worried about cylinder oiling just because this is a piece of equipment that would have very limited run time at any one time. Blocking a pair of intake runners and pulling outside air directly into a cylinder would be simple enough. Engines do run with misfiring cylinders.
firing order for the V-6 Is 1-6-5-4-3-2 and the earlier v-8 is 1-8-4-3-6-5-7-2. Obviously no way to get the two front or back cylinders in line with each other.
I appreciate you guys batting this around with me.
My first car in high school ws a 1953 chevy with a 235 cu. in. straight six engine and I had a tire inflator from the Sears Roebuck catalog that could replace a spark plug and had a hose long enough to air up all 4 tires. It had a check valve that allowed air in the cylinder on the downstroke and out the hose on the upstroke. Seems back then I always ran on poor tires and had to use it a lot.
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I think you could do it on two running cylinders. What would happen if you replaced the spark plug with a reed valve? Both valves closed on the compression stroke aren’t they?
as a side note, most of the higher output compressors are two stage.
The OTHER way to possibly get around this, is if you just need a short burst of 30cuft is to get a bigger tank like an old well pressure tank. I think the metal ones are rated to like 200psi (but double check). But the ones with a bladder in them, the bladder goes bad, not the tank but the bladder is like 250 dollars and the new tank is only 100 bucks more and I don’t think any plumber or well person replaces the bladder.
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I have replaced a couple of pressure tanks since we have lived here Sean. They are fairly thin metal compared to air compressor tanks I’ve built stuff with. I wonder just how much pressure they could hold. Two stage compressors are for building psi. A one stage will put out more CFM. I need volume and not pressure. A one stage pump is good for 125 psi. I have seldom used more than 100 at any give time, but yes. A suitable sized tank is an issue. I could put something together with the largest Harbor Freight air pump. It’s fairly cheap but takes a 5HP electric motor. There is at least another $350 to get one that will last more than a year like the $150 Chinese junk. Then I’m only getting 15 CFM which would be acceptable with something like an 80 gallon tank. I’m probably never going to do this project. I just want to hear opinions on the feasibility. Trapped in the house snow talk.
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According to the AO Smith manual for the 86 gallon tank, max working pressure is 100psi and check valves need to be installed. 
if you just need volume, an 212cc lawnmower engine is like 13.5cuft/min @3600 rpm, if you can get both upstrokes it doubles.
The largest HF air pump is 5hp? can’t you just run it with a 10hp garden tractor?
actually Ron Ohler might have an old 5hp electric motor he would be willing to part with that is most likely industrial… I don’t think I have one that big.
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TomH.
If a fellow was to actually do this it would be much easier to go old inline six cylinder and convert every other cylinder. Just as some were three cylinder converted in the false hope for better milage.(you can search this up)
My last owned a 1984 Ford I-6 300 cid had large base tapered seat spark plugs.
Pull the pushrods on the three cylinders to deactivate the valves.
Grind flush the three cylinders pins on the inside of the distributor cap.
Do your through the spark plug holes plumbing.
Steve Unruh
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That sound so cool. Did not know this. Thanks for the information.
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This makes sense SteveU. Does uncomplicate the conversion perhaps quite a bit. Since variable cylinder management has been around for a while now I don’t see any issues with oiling on the unfired cylinders and since the rotating assembly is hopefully already balanced I can’t see how firing or not firing any given cylinder could cause any additional engine stress. Not an engineer. I could be overlooking something there. At any rate a compressor pumping air out of a water cooled cylinder would be a benefit for heat dissipation which is always an issue for air pumps. Oil in the air stream has to be eliminated regardless. Anyways it give me something to think about while we are waiting for another 6 inches of snow overnight.
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Tom I am sorry to say that for fuel use economy the variable cylinder systems are all huge engine killing fails.
When GM Cadillac did this back when in the 1980’s the failure were attributed to lack of good high speed controls management.
Now that in the last 15 years GM, Dodge-Ram, and Honda all have turned their engines into oil sucking-burning failures.
Two there was failures in the switching valve train.
ALL have had develop the oil consumption problems later on the deactivated cylinders.
Those cylinders not kept combustion hot and uniform thermal stabilized. Increasing the mechanical wear in thier bores, pistons and rings.
Delete kit are extremely popular on the GM’s. Look it up.
For your air compressor idea no-matter as you just would not be using it that long hours after hours.
S.U.
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GM switched from active fuel management to dynamic fuel management. Dynamic fuel management uses 17 cylinder patterns rather then the active fuel management that just shut off the same cylinders.
I am guessing they rotate what cylinders they deactivate on the fly now which evens out and prevents wear because they can fire 1-2-3, the first rotation then 4-5-6 the next time, which keeps everything lubed.
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I’ve been looking at the Bourke engine as a potentially great engine for syngas. The problem is that they don’t make them anymore. In fact, they never made them on any kind of a commercial scale. There are a few open source projects with CAD files. Anyway, it’s interesting this engine likes to run lean and uses (allegedly) detonation vs. combustion.
Pretty cool…
Roger Richard has a great channel, and can speak to the Bourke engine probably better than anyone—he owns a few of the originals:
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Yeah Troy,
Pretty cool. I wonder what emissions are like. Come to think of it I wonder what the exhaust smells like. Something more I can learn about engines. I’m going to study more on this.
Btw have you checked out Anthony Michell’s ‘barrel’ engine? Variable stroke and variable compression ratio on the fly! I thought it would be the ultimate multi-fuel engine.
Rindert
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