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What are you creating that is larger than 227" in either direction?
If you want to use Illustrator { my personal design program of choice} Just draw it in a comfortable "scale" size {like 1/4 scale} then tell the producer of the work, to enlarge it by 400%, and your work will be exactly as you want it. the only caveat to this method is that you MUST remember if you are using screen tints, or jpg images in scale, that you MUST allow for the enlargement factor. IE. if you want something printed with a finished DPI of 150 DPI, you must create it at 600DPI at 1/4 scale. Then when it is enlarged to 400% at the time of production it will print out at 150DPI. I hope that is clear.
I have been using Illustrator for 15 years, and have ALWAYS worked at 10% of finished size, saved, and output at 1000% enlargement. Hits the mark, EVERY TIME. Just chose a "scale" that you always work in, and inform who ever is producing the finished artwork what percentage of enlargement you expect.