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Discussion Starter #1
"OK" I'm working on my "194" six this after noon and learned something!
Here is the story.

I set the new points to the .019 recommend gap install my trusty dwell meter start the car and it reads a dwell in the low 20 range.
Note: my dizzy does not have an adjustable dwell screw.
So, I know that this tells me that the points are gaped to wide.
So, I take the cap off and re-set the points to .015.
Start it up and the dwell is still below the recommend 31-34 range but, it is climbing.
So, I take the dizzy cap back off (again) and re-set the points this time to a tight .010.
Start up the car and lo and behold the dwell is dead on at 32 degrees!
I think this is the first time I've ever seen such a small gap needed to get the correct dwell!
So, be careful that just because the book states a recommend gap it does not always mean you'll get the correct dwell.

I take it for a spin and it runs great!
 

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72 Frame off, bare metal resto-mod. 383, TH350, Eaton Posi, Complete new suspension, disk brakes
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Check your timing

Okay, this may be some fuzzy memory stuff, but I remember the two working together. As you change the dwell, the timing changes a bit with it. That may explain the small gap. I'm assuming the points are new. If they are old at all the gap reading will be misleading because of natural pitting in the point faces. The meter will be your best guide there.
 

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:yes:dwell affects timing but timing dosnt affect dwell.a ryhme pounded into my knoggen from school days.
 

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i have gotten a lil more pizzaz from setting dwell at 29 deg,but...its hard on points lol
 

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Dwell is the master setting over gap.

What you missed!:D

The reason for your low gap to achieve the correct dwell is because your dist has excessive wear.

The distributor cam (Part that opens the points) has excessive wear.

FYI
Al
 

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Discussion Starter #8 (Edited)
Dwell is the master setting over gap.

What you missed!:D

The reason for your low gap to achieve the correct dwell is because your dist has excessive wear.

The distributor cam (Part that opens the points) has excessive wear.

FYI
Al
Brand new or er rebuilt dizzy from local auto parts store...
What should the cam spec out to be?
And, there is no side to side or up and down play in the shaft.

Pulled it, checked it over and you are right the cam gear is worn out! They must of not replaced it when it was rebuilt!
 
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