vacuum leak or dirty carb??

[70challengerdane]

ok so i pulled the vacuum advance line off of the dist and hooked it up to the vacuum guage, then set the initial timing to 15degrees btdc (i think the timing marker goes 0 5 10 "before" which i assume is the 15mark) and the idle picked up quite a bit and i was getting bout 13 inches of vacuum, so i put the advance line back on, backed the idle down to about 900 and readjusted the idle mixture screws and i also changed the springs out for the 5in orange springs and although its still not perfect and not totally ideal, it idles ok at about 900 in park, 500 in gear with the brakes applied, revs sorta smoothly to 6000rpm, and sounds decent. i also drove it down my long driveway and the trans feels tighter, and the car actually stops on its own power without dying. now i just need to rebleed the brakes and adjust them cause im only getting the rear brakes right now. but power assist is working as well. so timing and carb tuning seem to have been the main culprits for my problems. im still going to do more testing and the things you listed above after i get supplies from work but at least the bulk of the issue seems to be solved. thanks guys!!!!!!

 

[moparleo]

Glad to hear it.

 

[Chryco Psycho]

You are on the right track

 

[70challengerdane]

so question, how high would you guys recommend my initial timing be set at then? right now its as high as I can set it without being blind as the marker only goes to 15 before. should I just keep advancing it until its either hard to start or not improving the vacuum? or should I just leave it for now and move on to brakes? my compression should be in the 8.5 neighborhood so im not super worried about detonation where im at, but I also have open headers until I can get it running good enough to drive to work so I don't want to push it too far as I feel I wont be able to hear it detonate without any exhaust.

 

[Chryco Psycho]

15-20* seem to be about normal , you can certainly try it more advanced