I'm not sure what your main aims are here.
Are you trying to modify a lister so it can pass some arbitrary emissions test such as EPA?
If so, clearly it can be done, at a cost, there is ALWAYS a downside.
Let me explain my skepticism.
Some people in the states want to play with alternative fuels, and that is great. Now there were lots of "fuel analysis" engines made in the states, Caterpillar for one made vast numbers of them, because the best way to test an engine fuel is in an actual engine.
BTW the Cat engines were beauties, havent seen a 20/1 but I'd guess that's a similar size and weight, and lots of ancilliaries of course.
I would also assume that anyone doing this would acquaint themselves with the basics of combustion principles and thermodynamics, cos how else will you understand your results?
What we seem to get is people trying to make their feet fit the boots they happen to have, experimenting with multifuels in engines that weren't designed for it, and with no data acquisition ancilliaries whatsoever, seat of the pants stuff.
Fattywagon seems to be going this route from what I can gather, playing with EGR and suchlike.
To fattywagon, I am not trying to be insulting or flame you, but from what I have read it sounds to me as though you are exprimenting on how far you can de-tune a diesel by feeding it it's own waste products and still get it to run smoothish, with no attention paid to mechanical longevity or reliability.
I'm not knocking you, I think it is great that you're playing, but if you object is not mere play and learning, I wonder what you think you will achieve.
Say you get an "eureka" set of results. Just for the sake of argument (you won't, but for the sake of argument)
Where do we go from there?
Do I have to built an identical to the last detail system from scratch, and I mean identical to the thou EGR plumbing system etc, in order to duplicate your results?
Because it appears to me you don't have any data acquisition going on, none at all, so even when you get your "seat of your ass" results you are going to have to retrofit a bunch of DA hardware, and that is going to change everything.
If your goal is EPA emissions, you have two possible approaches.
1/ add a shit load of ancilliaries, microprocessor controlled, costing more than the listeroid, and absorbing at least 20% of the power output, and if you're going to do that you just threw away the only reason to run a lister, simplicity and longevity.
2/ reduce the effective swept volume to actual swept volume ratio and "fool" the EPA test that way
The above incidentally screwed norton when they built the rotary, because it was 2 stroke and not 4 stroke they rated it at 1500cc and not 750cc, so it couldn't compete in its design engine capacity class. This is as silly and arbitrary as EPA regs
There are two ways to screw with effective swept volume ratios
a/ screw with valve duration, which you are doing, and EGR is a wrinkle on that same theme, screwing with effective swept volume... it is a limited ploy and not something I'd consider with a lister, which is all about simple, so no point doing anything that makes it complex.
b/ screw with the camshafts, nobody says it has to be a 4 stroke, make it 6 stroke or 8 stroke and you'll beat those emissions regs, especially if you use those idle strokes to do something else, like injecting water.
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The lister is like a good knife, it is elegant because of its simplicity, purity of form, minimalism, form following function, the only techie thing about the lister, and even by todays standards it is techie, is harry ricardos comet precombustion chamber, if you have a listeroid that doesn't have this then you are more screwed than ever when it comes to EPA
I must at some point put my lister through a vehicle emission test, it's a 6/1 relatively lightly loaded with a standard 2.5 kw head, and I'm betting it runs as clean as my indirect injection non turbo all mechanical 1900 cc 4 pot renault car diesel, which is really very very clean indeed, especially on european diesel.
Just because the design is 60 / 70 / 80 years old, doesn't mean it is bad, just because it was from before transistors and microelectronics and plastics, doesn't mean it is bad, some of the best knives are 100 year old designs.
The poppet valve is over a century old, it has its issues, but nobody has invented anything better, and this follows all the way through the lister, there aren't superior modern alternatives to any component, just cheaper ones.
And this brings us back to proper ricardo test engines and their clones
picture below
The fact is, this is the minimum level of kit you need to do these experiments and end up with results that are worth more than the paper they are printed on.
You can go out and buy one of these engines for big bucks, or build one up, for big bucks, that's it.
If it is all about a dream, fine, but SAY SO, don't tell other people your dream is reality, because they have different dreams.
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I have an old litmus test for this sort of thing.
I say to myself (about my latest greatest world shattering plan / invention / creation / scheme / whatever) "will a bank lend me money to go into production with this idea?" and god knows it is too easy to borrow money anyway.
I grew up reading "Boys Own" books, about the nice guy who got shafted by the nasty people who used him and discarded him building their racing cars, so he goes to the scrap yard and buys an old car and does it up and enters the race and WINS!!!!
Maybe that shit was possible 80 years ago, it isn't today.
You think you can maybe not compete on budget, or tech facilities at your disposal, but maybe have some idea that nobody else had before? Your idea better be implementable for 50 cents then, so ceramic coatings for the combustion chamber to limit absorbtion of free electrons and thus slow flame propogation are out.
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here's a thought for you.
fuel is about work done.
you have a job of work to do, move 10,000 tons of foodstuffs daily 200 miles into a big city.
diesel engines are far more efficient for this task than petrol, thanks to the high compression ratios.
diesel engines are far more polluting according to the EPA and NOx emissions, thanls to the high compression ratios.
low compression engines will satisfy the EPA and NOx emissions, but you do three or four times as many trips because tons of load shifted per gallon of fuel used just dropped through the floor.
so the stinky high compression diesel pumping out NOx actually pumps out LESS to do a given job than EPA complaint green low compression engines.
