This is approximate, but figure around an hour for a bird of that size at 325-350. I like to let 'em sit out while the cooker is coming up to temp. I'll actually let 'em sit out for up to an hour (but not if company is over 'cause people get flipped out over that kinda chit). This is for a spatchocked (butterflied) chix btw - haven't done an uncut one in ages.
A whole 'nother subject, but if you wanna spatchcock, cut out the spine, cut into the cartilage between the breasts and use your fingers to work out the keel bone. I think there's a good tutorial video on the Virtual Weber Bullet site, and I know there's no shortage of info around here.
Also, when you pat your chix dry after taking it out of the brine (you might wanna rinse yer bird btw), pat it dry and apply the rub. Let it sweat - i.e. the rub hydrates. I usually use a seasoned salt first then the rub, thereby sweating it twice.
Or you could just throw the farking thing in the cooker till it's done and it'll still be pretty dang good.
I've been cooking at least one every week for a very long time and I still love it. Lots of possibilities with flavors, etc. plus it's always good to have some chix in the fridge for quick meals, kids' school lunches, work lunches, etc.
btw the method outlined by bucc is fantastic.
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