Upper part.
I'll have to check that out. Hope you can find it Johnny, I am interested in that. Let me also, add that according to Aaron at Bad Ass Racing Engines he also hooks them at the top (I have a really good carb video from them).69NovaSS said:the ported vaccum is what GM and others switched too in an effort to help MPG and emissions(in the 70's sometime)....but based on the vacuum advance 101 thread at Steves it didnt work worth a damn...