Re: intake manifold
Well just my two cents, probably not a good plan to utilize anything from the stock intake given you intend to braze. I had originally planned on brazing a copper 45 degree fitting to mine. Within seconds of introducing heat while testing, the pot metal casting melted like butter. With nothing to loose I attempted to flatten the destorted flange and it fractured revealing the inferior composition. Maybe someone else has perfected the technique but I ended up just fabricating the whole thing.