SuperSport said:Upper part.
thats what I said and thats what you want....you want full vacumm at idle....you will only get that from the lowest ports...so as Johnny said hook it up there...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...SuperSport said:Yo, 69. I believe the lower ports are sucking on idle and the top ports suck on acceleration.
Wow, more confusuion or I am just an idiot? (I am leaving myself open to some serious smack talking if I am wrong).
Based on ignitionman that would be wrong (if my memory is right)SuperSport said:Holley's website has the insrutions on there. I do not know why this site does not let me cut and paste the link here. It shows the distributor vacuum line to the top.
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...
Well look at it this way normally when you set the timing the vac line is disconected but then you hook up the vac line which WILL normally advance the timing EVEN at idle...and then as you accelerate the vacuum will fall off of the lower port but at the same time your mechaniical advance will take over and give your total advance...SuperSport said:Well, like I said holley is showing you to connect it on top. It was my understanding that you want vacuum on acceleration for the dist. . But, hey it's only holley's instructions I am going by.