i bought a manifold from turbo-performance for a custom setup for my accord f22b1... they fucked up on the order and they accidentally chrome-plated mine for free... anyway, i went to my boy's shop to check out all the parts... this is a pic of what my manifold basically looks like... he laid the longer flange side onto flat glass and there seemed to be a problem... the left and right ends of the flange was not as flat as the center... so they were a tiny bit raised... it's about 2-3mm gap from the surface of the glass i think on each side... i called turbo-performance and they said it's fine and to get a new gasket... retighten the bolts, etc., after first 50 miles of boosting... now i'm wondering if i should go to a machine shop to resurface the flange so that it's close to perfectly straight or just get a new gasket from honda or something...