those are your tab/tad and egr. they go from a single port off the intake, split into two and goes to the tab/tad solonoids, then down to the two valves on the pass side connected to the smog pump tubing. they're responsible for switching the air to the heads when cold, then to the cat's while warm.
can't tell from the pic and your setup is a little newer than mine, but one may be egr too, and that will go from intake vacuum to the egr solonoid to the egr, usually it's the white one.
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