if you ever manage to drop a nut/bolt down an inlet manifold thats curved, and a straight magnet just wont reach around the bends, obtain an old speaker magnet thats been removed off the speaker not too large, and run it outside/underneath the manifold and listen for the catch. once you've "caught" the object try to run it up the walls of the manifold slowly, then use the straight magnet to reel in your catch. may take a few shots but. if the object is not magnetic, a useful tool is one with a claw that expands when pressed and grabs when released. these are quite long and are flexible too.