Snorting Vicodine creates a series of difficult questions.
The mucous membrane typically has a faster uptake of the medication than taking it per os. However, the membrane can clog, thus stopping uptake altogether. This means that the transfer time into the plasma is indeterminate; it make be faster or slower than taking it Per Os (as the drug was intending to be administered).
What's more, no-one has clinically examined this question, and there is no detailed, factual study to refer to.
As ultra-rapid uptake of a medication has a lot in common with overdose risk, and considering that a medication like hydrocodone -- a respiratory depressant -- has an overdose risk when using the normal tried and true mode of administration, I'd say snorting vicodin is a lot like playing Russian Roulette.
I can't predict the results, guess at the OD limit, or recommend this method of administration. I would advise against it.