Unfortunatly no there isn't. Turbo headers don't exist for any Z other than the 90+ 300zx. To be more specific there are no turbo headers for the older Z avaliable here in the U.S. but I'm sure Japan companies at one point made them. The three options I see here are to find a set in Japan through company that will ship to you, have a set custom made, or stick with the stock manifold and just have it ported by a machine shop.