Author Topic: Using vacuum gauge for adjusting idle mixture method?  (Read 3391 times)

Offline Chryco Psycho

  • Administrator
  • C-C.com Guru
  • *****
  • Posts: 36620
  • 70 Challenger R/T SE 70 tube Chassis Cuda now sold
Re: Using vacuum gauge for adjusting idle mixture method?
« Reply #15 on: October 17, 2008 - 01:57:38 AM »

with 18+ " of vacuum the cam has to be relatively mild , I would disconnect the vacuum advance or use a hex key & dial most of it out by turning the hex key CCW  , run the initial timing up to 14-16* , it should run a lot better

Challenger - You`ll wish You Hadn`t




Offline Katfish

  • Resident
  • *****
  • Posts: 3733
  • 70 Challenger
Re: Using vacuum gauge for adjusting idle mixture method?
« Reply #16 on: October 17, 2008 - 09:47:47 AM »
I'll check the timing again.  The car actually does run pretty good, no complaints.  But as was mentioned the eye burning stinky smell is aweful.

Would disconnecting the vacuum advance help with this?

Offline Chryco Psycho

  • Administrator
  • C-C.com Guru
  • *****
  • Posts: 36620
  • 70 Challenger R/T SE 70 tube Chassis Cuda now sold
Re: Using vacuum gauge for adjusting idle mixture method?
« Reply #17 on: October 17, 2008 - 11:50:13 AM »
no but advancing the timing will & to do that you need to reduce the timing curve so you are not overadvanced at higher rpm

Challenger - You`ll wish You Hadn`t

Offline moper

  • Resident
  • *****
  • Posts: 2368
Re: Using vacuum gauge for adjusting idle mixture method?
« Reply #18 on: October 23, 2008 - 11:30:21 AM »
You always set timing first. Initial settings CP likes are what i use to... 15-20 depending, but basically as much as it will take. IN terms of setting misture after that.. You go with the best (highest) vacuum reading. So by going leaner than 19.5 to get it to drop vacuum to 18.5,  you run the risk of putting it into lean misfire.

Offline rabarrett

  • Jr. Member
  • **
  • Posts: 6
Re: Using vacuum gauge for adjusting idle mixture method?
« Reply #19 on: October 24, 2008 - 04:17:33 PM »
It is usually the HC's or unburned fuel that stinks. With a 19.5" vacuum, if that is the highest, go slightly leaner until it drops, then go rich to just recover the vacuum reading. That is called the best lean idle. Slightly lean or very rich both lead to stinky exhaust, due to the unburned fuel. Excessively rich also smells like fuel, and offers a slight Rich "roll."

Offline BIGSHCLUNK

  • Sr. Resident
  • ******
  • Posts: 9341
  • Miss NIKKI - were you this hot at 48?
Re: Using vacuum gauge for adjusting idle mixture method?
« Reply #20 on: October 24, 2008 - 04:33:09 PM »
I had a raw gas smell from my exhaust last summer. (750DP  Holley) replaced the power piston and  it went away..
70 Chally R/T Convertible- Yes she's really got a HEMI, no she's not a Charger!
                                             [o o o o]
                                                  OO
                                                  OO 
                                              [o o o o]
https://www.aanddtruckautoparts.com/
http://www.facebook.com/pages/A-D-Truck-and-Auto-Parts/67427352555?ref=hl

Offline femtnmax

  • Full Member
  • ***
  • Posts: 997
Re: Using vacuum gauge for adjusting idle mixture method?
« Reply #21 on: October 29, 2008 - 10:37:58 PM »
I just submitted a post for tuning my Edel AVS carb.  May be of some help.
Phil