New 408 stroker runs rough at idle

Johnny Mac said

We're at 2150.
You loose approx 1 inch per 1000. But our ratings are conservative. Your reading still feels low.
Will it rev clean once you get it to "catch up" and pass the stumble?
What do your plugs look like?
What is total timing at?

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So with it not wanting to run it turns out it already ran out of the 5 gallons of gas I gave it. Put another 5 gallons in it and now it runs. It just seems like at idle, it runs rough, but once you raise the rpms to about 1500 to 2000 it doesn’t shake so bad. The plugs are black already. I have yet to check total timing. On the site, it says 10-16 initial, if I can shorten the amount it advances, so it doesn’t go above 34 degrees, could I have the initial timing considerably above 16 degrees, like 20-25 degrees or is that really not recommended? I just have the initial set at 16 as of right now. I haven’t yet checked total timing.