1967 - 1972 F-100 & Larger F-Series Trucks Discuss the Bumpsides Ford Truck

390 timing

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Old 08-12-2012, 08:39 PM
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390 timing

Just did a rewire, new ignition, condenser, plugs/wires, etc, and somehow my timing got all jacked up. I just reset it to 10* ... It cranks right up and runs smooth, but it seems to not have the power it did before. Any suggestions for setting the timing so it's more aggressive? It has an Edelbrock carb/intake, but stock exhaust manifold and some crappy mufflers.
 
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Old 08-12-2012, 08:43 PM
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"Somehow the timing got all jacked up"? How does that happen do you suppose? You need a timing light.
 
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Old 08-12-2012, 08:47 PM
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Uh, yea, I have a timing light. Was asking for suggestions on a good setting. Would 12* be better?
 
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Old 08-12-2012, 08:54 PM
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Throw the timing light on the bench. Loosen the distributor just enough to be able to move it. Fire the beast up. Advance the timing, test with acceleration. Keep advancing until acceleration drops off a bit. Now let it warm up. Turn it off. Will it start or does it drag like a dead battery? Drag - yes back it off just a hair. Try to start it. Repeat until it starts ok when hot. You now have the timing set. You can check it with a light just to make you feel better.
 
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Old 08-12-2012, 10:04 PM
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Originally Posted by elgemcdlf
Throw the timing light on the bench. Loosen the distributor just enough to be able to move it. Fire the beast up. Advance the timing, test with acceleration. Keep advancing until acceleration drops off a bit. Now let it warm up. Turn it off. Will it start or does it drag like a dead battery? Drag - yes back it off just a hair. Try to start it. Repeat until it starts ok when hot. You now have the timing set. You can check it with a light just to make you feel better.
^^Good stuff^^

Soco I could write a book on setting timing, the question is how involved you want to get, otherwise the above is a good start.
 
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Old 08-12-2012, 10:13 PM
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I'm going to give that a go tomorrow. Thx all!
 
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Old 08-13-2012, 08:58 AM
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if truck ran fine before new cap,rotor,plugs and wires then runs poor , i'd say you either have some wires mixed up or one wire is not 100% connected to cap or plug .
if you didn't touch dizzy hold down there's no way timing changed .
 
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Old 08-14-2012, 04:38 PM
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Originally Posted by MIKES 68 F100
if truck ran fine before new cap,rotor,plugs and wires then runs poor , i'd say you either have some wires mixed up or one wire is not 100% connected to cap or plug .
if you didn't touch dizzy hold down there's no way timing changed .

Could be...

When the OP says "Module", do you think he replaced the points? Perhaps his dwell is off...

Just throwing it out there. Not sure if he is running a converted ignition or not, but I assume not because he replaced a condenser...

Either way, if he didn't set his points properly, and gapped his plugs incorrectly...

Just sayin... For what he posted, his dwell and plug gap could be off enough to give weak spark, affect performance, and alter timing...
 
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Old 08-14-2012, 05:05 PM
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Thumbs up running bad

times 2 Wildcat, You cannot beat a dwell meter for getting the points right.
 
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Old 08-14-2012, 05:25 PM
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Originally Posted by kenny nunez
times 2 Wildcat, You cannot beat a dwell meter for getting the points right.
Yeah, kenny, but I actually am more concerned if the OP even gapped the points going in... Never mind using a Dwell meter to dial it in to a gnat's ***... or for diagnosis... The plugs kinda concern me too...

That all has to be resolved before timing.

I have no reference on the OP's experience level, but you can't just drop stuff in a 40 year old truck and then wonder WTF?

It's old stuff... It wants YOU to know what you are doing... and tell it what to do.
Definitely NOT plug and play...

If that makes any sense.
 
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Old 08-14-2012, 11:34 PM
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As part of "etc" it may have been retimed- In which case it may have been adjusted with the vacuum line hooked up which will retard the timing. When I got my Courier, it would fire right up, run smooth, but had -zero- power. I attributed this to it's being a four cylinder, but when I did the timing belt, I reset the timing properly and it actually was able to get out into traffic.
 
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Old 08-17-2012, 11:11 AM
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I have a 1973 F350 SCS with a 390cid and a 4 spd. The engine still has points, can someone tell me what the timing and points are at factory settings? The truck is not currently running. Thanks!!
 
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Old 08-17-2012, 03:31 PM
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From memory, and for a 1971, but should work for you:

Point gap .017"
Dwell 26-31 degrees
Timing 10 degrees BTDC (This with vacuum hose disconnected and plugged, and at 625-650 RPM)

Hope it helps
 
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Old 08-17-2012, 04:05 PM
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THANKS!!

It does help a lot!! I will be out there first thing in the morning!!
 
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Old 08-18-2012, 08:31 AM
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Originally Posted by Mtlrcks
I have a 1973 F350 SCS with a 390cid and a 4 spd. The engine still has points, can someone tell me what the timing and points are at factory settings? The truck is not currently running. Thanks!!
If I remember right the official gauge to use for the points is a matchbook cover. I got many running again using that. Always kept a book of matches in the glovebox
 


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