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more progress, more questions... idle speed and vacuum

  • Thread starter Thread starter Stang_1973
  • Start date Start date Mar 15, 2009

Stang_1973

Founding Member
Jul 13, 2001
565
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38
San Antonio, Tx.
Mar 15, 2009
#1
  • Mar 15, 2009
  • #1
Ok so i think i found the culprit for my idle speed being too high. I went by spraying some carb cleaner around vacuum lines and intake and carb. noticed a drop in rpm when spraying where the vacuum line that goes to the tranny goes into the carb. sure enough, it seems to be a bit big because it very loose to come off. im gonna switch it out for a smaller diamter hose. see what happens.

As for checking vacuum, i also noticed something. After watching a few vids on youtube, i learned that to adjust your idle misture, your really tuning for vacuum. So after hooking up the vacuum gauge into the same hook up(the one that goes to the tranny) i started to tune for best vacuum.

I backed in both misture screws and backed out 1.5 turns, at about 14 inches...

so i started going up on both screws but never achieved any better. so i decided to put them farther in. low and behold, i screwed them all the way in and got up to 15 in. what?! also according to the vids i saw, by screwing them all the way in with the engine on, my engine should have died! im guessing a blown power valve now.......

Did i do this right? should i hook up gauge from somewhere else. Also if my power valve is blown does that mean my secondaried arent working?

looking forward to hear some responses.
 

woodsnake

15 Year Member
Jan 16, 2007
1,352
15
69
Hicksville, NY
Mar 15, 2009
#2
  • Mar 15, 2009
  • #2
You want to tune for your best vacuum. Idle speed itself is set at the carburetor. Afer you replace the vacuume line that goes to the trans, set your timing, after you set your timing make your carb adjustments, I.E. idle mix.

Then, go back and make changes as required.
 
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