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Author Topic: timing adjustment  (Read 3341 times)

Offline Chryco Psycho

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timing adjustment
« on: March 03, 2004 - 02:13:48 AM »
The engine spend 90% of the time running at full advance above the advance curve so it is more important to have the timing set there than at idle. Most engine want more intial advance at idle than the factory curve will allow

Set the timing between 36-38* above 2500 rpm [ I usually turn the idle speed screw up to keep the rpm steady]with the vacuum hooked up , if it is over advanced you can hear it pop/ misfire in the exhaust.
I f you do not have a timing lite with the advance feature you can put a mark or cut into the damper 2 3/8" clockwise form TDC this is 36*

Now reset the idle speed & now try advancing the timing at idle , if the idle speed picks up it wants more initial timing so you need to shorten the curve.

You can put a small allen wrench into the hose nipple on the vacuum advance unit & turn counter clockwise to reduce the amount of extra advance the vacuum gives you & shorten the timing curve  [it will turn approx 14 turns total & will not hurt anything if you unthread it too far]

Now reset the timing above 2500 RPM  & try again at idle until it runs best both at idle & above 2500 rpm

I f you completely disable the vacuum advance & the engine still wants more advance at idle with the total timing set properly  the only option is to disassemble the dist & put a small tack weld in theslots for the advance weights which will shorten the curve even more

You will probably be surprised how much better the gas milage , response & power you will be adjusting the timing this way


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timing adjustment
« on: March 03, 2004 - 02:13:48 AM »



Offline DocMel

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Re: timing adjustment
« Reply #1 on: February 25, 2011 - 02:30:04 PM »
I appreciate the help, but not the exact post I was looking for. 

The one I was looking for was even simplier:
Basically, rev up to and hold at 2200 or 2500:  Then rotate distro until highest rpm is acheved, then back off slightly

I cant remeber:

1.  If it was held at 2200 or 2500
2.  Is vacum hose attahced or detached/plugged while you do it

Online MEK-Dangerfield

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Re: timing adjustment
« Reply #2 on: February 25, 2011 - 05:00:00 PM »
I appreciate the help, but not the exact post I was looking for. 

The one I was looking for was even simplier:
Basically, rev up to and hold at 2200 or 2500:  Then rotate distro until highest rpm is acheved, then back off slightly

I cant remeber:

1.  If it was held at 2200 or 2500
2.  Is vacum hose attahced or detached/plugged while you do it


1. I would Rev to 2500.

2. Vacuum hose is detached and plugged so air isn't getting sucked into the carb

Mike

1970 Challenger - SOLD
2013 SXT+++++++++++

Online dougs bs23

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Re: timing adjustment
« Reply #3 on: June 07, 2012 - 10:13:51 AM »
Set the timing between 36-38* above 2500 rpm [ I usually turn the idle speed screw up to keep the rpm steady]with the vacuum hooked up , if it is over advanced you can hear it pop/ misfire in the exhaust.
I f you do not have a timing lite with the advance feature you can put a mark or cut into the damper 2 3/8" clockwise form TDC this is 36*   
Doing this and where do you line up the mark on the case marks?  right at 0 or where?
see Bill run  go Navy football///fly navy

Offline jhaag

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Re: timing adjustment
« Reply #4 on: February 19, 2013 - 08:50:39 PM »
another :2cents:    this procedure was passed to me by some old timers to set initial timing without a light. conect a vacum guage to manifold vacum. slowly advance timing until you get the highest vacum reading. back the timing down several numbers and slowly advance again until you reach 1 inch pound of your highest reading.

example: advance until you get highest reading of say 20: back timing down to 15: slowly advance again until your vacum guage reads 19 and lock it in there.

This will help you set initial timing but not total timing.
love 70 Challengers

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Re: timing adjustment
« Reply #4 on: February 19, 2013 - 08:50:39 PM »