reusing gaskets is a bad idea. They have been crushed once and formed to the unique shape and surface of the mating parts. once they have been *un-sealed* they dont have any more thickness to be re crushed and seal. thick metal gaskets may let you get away with a couple re uses but a paper gasket is a one time use. They are so cheap that there is no reason not to use a new one, anyway. IF you absolutely have to re use a paper gasket its a good idea to seal it with a fuel system thread and gasket lubricant like EZ-turn seal lube. Since there will be fuel in the intake chage as it passes that gasket, a fuel resistant compound is ideal. I put this stuff on all paper gaskets and metal/metal threads. it increases the gaskets life and pressure holding and allows the gasket to be removed later without tedious scaping and on threads it prevents galling and helps seal. A high temp RTV could work, too. But it tends to shrink over time so a leak may be likely down the road.