If you adjust the valves, you'll likely pull the intake off again for access. The points where the intake attaches to the head are a notorious trouble spot for air leaks causing a surge condition. New gaskets here are not enough in my experience. Clean the area thouroughly and put a generous bead of black high temp silicone all the way around both intake attachment points (along with new gaskets). Sometimes, after so may years those intake surfaces are no longer flat, and it's hard to resurface that. The silicone sealant overcomes this. Made a huge difference on my 318/B43G.