440 Six Pack, is my vacuum too low?

[KillerBee]

Checked the vacuum on my 440 Six Pack today.

Removed the rear plug on the intake replaced with barbed fitting and took the reading there.

Engine is a close to stock 1966 440 with MP .528 solid with 284 advertised duration?

4 speed transmission

The vacuum was 7-8 hg at idle.

I don't think the vacuum gauge is bad.

Distributor is locked out with lighter springs, no vacuum advance, distributor and center carb ports are plugged, total timing is 37

The car runs and idles real nice, no signs of any vacuums leaks, car pulls strong and it sounds and feels like the outboard carbs are opening up correctly.

The only issue I noticed is the the center carb air mixture screws don't change much when turned in or out but I'm thinking that's because I currently have a 6.5 power valve in it as I was expecting 12-13 hg vacuum when I set up the carbs.

So should I be concerned or is this normal vacuum for my cam?

Should I just swap out to a 3.5 or 4.5 power vavle and move on?

Thanks.

[Chryco Psycho]

I would drop to a 4.5 PV
 Vaccum should be OK but if you make a U shaped wire from mig wire or similar & slide it into the idle bleeds in the middle carb & trap the wire behind the squirter I bet the idle mix will clean up , there are also mixture screw on the end carbs under the bowls , the rear is difficult to adjust so I set around 1/2 out from bottomed out , the front carb is easily adjusted .

[KillerBee]

I would drop to a 4.5 PV
 Vaccum should be OK but if you make a U shaped wire from mig wire or similar & slide it into the idle bleeds in the middle carb & trap the wire behind the squirter I bet the idle mix will clean up , there are also mixture screw on the end carbs under the bowls , the rear is difficult to adjust so I set around 1/2 out from bottomed out , the front carb is easily adjusted .

Thanks for the info.
Got any pics of the wire modification?

I bought the tool and special screws for adjusting the rear carb and both outboard carbs seem to respond well to tuning, the center carb seems to be the troubled one but the car idles down real nice and steady.
http://board.moparts.org/ubbthreads/showflat.php?Cat=0&Board=Deals&Number=7046838&Searchpage=1&Main=7046838&Words=+69sixpackbee&topic=&Search=true#Post7046838

Here a video of the car running.
 http://s260.beta.photobucket.com/user/71rtchallenger/media/IMG_0403.mp4.html

[Chryco Psycho]

nothng handy to work with or take pix of , if you look at the front wall of the center carb under the choke you will see 4 small brass inserts with tiny holes in them , the outer ones are for the idle circuit & respond if you restrict them with a thin piece of wire .

[KillerBee]

nothng handy to work with or take pix of , if you look at the front wall of the center carb under the choke you will see 4 small brass inserts with tiny holes in them , the outer ones are for the idle circuit & respond if you restrict them with a thin piece of wire .

Got it.

The same outer ones you restrict to adjust the outer carbs except the wire stays in the holes permanently in the  center carb.

Any idea what size or gauge wire I should try?

[nqkjw]

Soldering wire is best and easiest to use for this mod.
It's soft so is easy to bend and push into place.

[Chryco Psycho]

solder is ok if you ant to block the holes completely , generally I just restrict the holes , .030 or .035 mig wire should make a difference immediatly to see if you are on the right track

[Cuda54]

Just wonder if you checked the outboard carb linkage. Disconnect them and see if the carb shut totally.  Then check the linkage to see if it is the right length to fit the hole without moving anything. If one is not closing it will act like that.