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Initial timing setting question
https://www.slantsix.org/forum/viewtopic.php?t=62295		 Page 1 of 2
Author:  MrFusion [ Thu May 03, 2018 10:04 pm ]
Post subject:  Initial timing setting question
I've read through a number of threads and am a bit confused about what my initial timing setting should be. The engine is a 1982. The ESC has been replaced with a vacuum advance electronic distributor, Holley 1945 non feed back carb (will post specific part number tomorrow), EGR deleted, Air pump deleted, SSD's HEI conversion, Autolite 26 plugs gapped to .045", automatic trans, 111k miles.

Since the underhood sticker no longer applies I'm not sure where to set the initial timing or for that matter what rpm i should be setting it at.

Thanks.
Author:  DadTruck [ Fri May 04, 2018 9:02 am ]
Post subject:  Re: Initial timing setting question
you are absolutely correct, the factory timing specifications no longer apply after the engine-ingnition has been modified.

to figure out an initial advance setting I would back into that number like this

slants seem to like around 32 degrees of total advance, depending upon the distributor that you have the mechanical advance may be 22 degrees, an 11R regulator which is fairly common has 22 degrees, a 9R a little less common has 18 degrees...

32
-22 ( 11R regulator)
____
10

so go with 10 degrees of initial, as a starting point, you can expect that as you add initial timing the idle RPM will increase,
bring the idle back down so the mechanical advance is not activated. Then fine tune (add more) the initial advance to improve driveability.
If you experience pinging under load, take some of the initial timing out.

a reasonable idle speed is 800 to 900 RPM, you can go lower ( 600 to 700 ) if the engine is in good operating condition.

if your vacuum advance needs to be on ported or manifold vacuum is another question.
If you are running manifold vacuum to the distributor be sure to disconnect the vacuum can line when setting initial timing and plug the line to the carb stop the vacuum leak.
Author:  MrFusion [ Sun May 06, 2018 9:41 am ]
Post subject:  Re: Initial timing setting question
Thanks for the advice sir! I have it set around 10 degrees advance right now but will try some fine tuning in the next few days. Its a bit confusing because I had to change the carb and distributor at the same time. I'm sort of stuck in a chicken or egg adjustment loop. Haha.
Author:  DusterIdiot [ Sun May 06, 2018 11:45 am ]
Post subject:  Re: Initial timing setting question
The other quick and dirty method to set an unknown distributor is (assumes damper is correct and not slipped): warm up engine, disconnect and plug the vacuum advance hose, set the engine idle screw to 3000 rpm, using timing light check the current advance, adjust distributor until your timing is at 30, set the distributor, reset the idle screw back to normal idle, reconnect vacuum advance and take for a test drive in varied traffic and terrain and check for ping/rattle. If not ping, you are done, if you have ping, back off 2 degrees and test drive, repeat as necessary.

If this is a cardone reman, the most common distributor will be the 1973-1975 15L mechanical advance, which is supposed to be set at TDC, but can be set more to 5BTDC due to the stiff spring
set...If you got lucky with a 9 or 11 governor you can go more on your initial...FYI.
Author:  MrFusion [ Sun May 06, 2018 8:36 pm ]
Post subject:  Re: Initial timing setting question
Thanks DI! I'll try it. The timing mark on the balancer lined up with the 0 mark at TDC so I don't think it slipped. TDC was confirmed with a rod down the spark plug hole, watching the valves, and position of the rotor.
The distributor is an Autoline reman that I believe you suggested in a previous post. I forget the model off the top of my head (619 maybe). SSD suggested an NOS part from OAPNW but I didn't want to rebuild one and i tried calling them 5 times with no response. I ordered the Autoline from Rockauto.
Author:  ChrisHolley [ Sat May 12, 2018 9:40 am ]
Post subject:  Re: Initial timing setting question
This is a link to a little story I put together for Mopar Connection magazine. This story is about setting up the distributor for performance, and later this year the economy story will be available in the magazine.

http://moparconnectionmagazine.com/more ... slant-six/

Just some more ideas on setting up your distributor
Author:  MrFusion [ Wed May 16, 2018 3:18 pm ]
Post subject:  Re: Initial timing setting question
Thanks for the link to the article. Very informative.
Author:  MrFusion [ Sat May 19, 2018 9:57 pm ]
Post subject:  Re: Initial timing setting question
While I was thumbing through the FSM I found the initial timing spec in the fuel system section :?: . Accordingly the /6 automatic Federal Emissions static timing spec is 16* BTDC. Using a vacuum gauge and timing light I have mine set to that approximate spec. At 800 RPM idle the engine is drawing approximately 19 in/Hg. Truck runs and drives acceptably. I don't hear any pinging.

I had a problem with loss of power (power... :lol:) and stalling at idle after a few minutes of driving. The first time I gassed up the pump kept clicking off. I had run the pump at half speed to avoid that. I drove another ten mile or so with the filler cap off (purposely) and the problem went away. Apparently the tank vent is plugged. That's a problem for tomorrow.

On another note: Good lord is this thing slow!! I didn't expect much out of the slant/auto but jeez...
Author:  DusterIdiot [ Sun May 20, 2018 8:28 am ]
Post subject:  Re: Initial timing setting question
Quote:
While I was thumbing through the FSM I found the initial timing spec in the fuel system section :?: . Accordingly the /6 automatic Federal Emissions static timing spec is 16* BTDC. Using a vacuum gauge and timing light I have mine set to that approximate spec. At 800 RPM idle the engine is drawing approximately 19 in/Hg. Truck runs and drives acceptably. I don't hear any pinging.
Ummm....

The timing spec is for the ESC system, once you change to a mechanical advance distributor you disregard the book as the mechanical and vacuum advance will dictate the actual
range to set the initial... One issue with over advancing the distributor if it doesn't ping/detonate will be that the carburator may need to be jetted richer...

Another question is, if it drove acceptably did you drive it with the vacuum advance hooked up under the same conditions?
Author:  MrFusion [ Sun May 20, 2018 9:49 am ]
Post subject:  Re: Initial timing setting question
Yes vac advance was hooked up. I tried your method but forgot to disconnect the vac advance. I'll try it again the right way in the next few days. It seems to run a bit better with the initial advance at around 16*. It will certainly take some more tweaking.
I will probably post another thread with questions about Holley 1945 tuning.
It is having another problem as well that I will create another thread about that.
Author:  sandy in BC [ Sun May 20, 2018 10:27 am ]
Post subject:  Re: Initial timing setting question
Get your timing right using Dusteridiots method before messing with the carb.

That distributor you have installed needs a specific initial setting.

You should also adjust your valves before messing with the carb....but get the timing right first.
Author:  ceej [ Sun May 20, 2018 10:13 pm ]
Post subject:  Re: Initial timing setting question
With the EGR delete, you may need to limit the amount of vacuum advance as well. I think DI had some numbers for different Vac Advance cans and adjustments floating around at one time. DI?

CJ
Author:  wjajr [ Mon May 21, 2018 6:05 am ]
Post subject:  Re: Initial timing setting question
ChrisHolley, nice write-up on distributor recurving.
Author:  DusterIdiot [ Mon May 21, 2018 5:21 pm ]
Post subject:  Re: Initial timing setting question
Quote:
I think DI had some numbers for different Vac Advance cans and adjustments floating around at one time. DI?
No, but SlantSixDan had a list of available pods...but with time marching on there are only a couple options for advances...and they
are fairly close in advance and adjustment anyway... but hard to recommend anything without knowing what he's currently got
dialed in...
Author:  MrFusion [ Tue May 29, 2018 10:16 pm ]
Post subject:  Re: Initial timing setting question
Thanks all for the advice!

ChrisHolley thanks for the link.

DI - I tried your method 2x. I must have done something wrong. I ran the /6 as close to 3k as i could (2900 according to my Chicom tach) the high idle screw was bottomed on the cold idle notch, engine warm. I set my advance light to 30* advance and turned the distributor until the timing mark was on 0*. Vacuum advance disconnected. When I checked the static timing at idle it was 22* advanced both times. Obviously way too advanced. I set the static timing back to approximately 15* advance at idle where it seems to be happy. Am i missing something?? Thanks!

Also had a revelation on the carb. The "NOS never been run" Fleabay 1945 carb I bought kept stalling out after WOT runs. I took the top cover off to check the float height (which was way off, low) and the fuel bowls were full of gray sludge and the other internals were covered with corrosion and varnish powder. Ahhhh the joys of ebay.

Rebuild kit ordered and 3 cans of carb cleaner dumped through every hole I could find.

It never ends with this thing....
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