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Discussion Starter #1
When I gap my points (289) per factory specs and set timing to 8-9 btdc my engine has bad hesitation problems as I accelerate.

When I set the gap smaller and retime to the same setting, the hesitation is gone.

Idle is fine under both settings.

Actually I am using a dwell meter to set gap. Dwell reading goes up as gap decreases. Dwell around 30 is what specs say but mine likes 40.

Can anyone help me understand why my engine likes this smaller point gap setting?

All tuneup related stuff is relatively new, engine is stock, vacuum around 19 steady at idle, engine appears to be in good shape.

Thanks, Doug
 

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The gap of your points is relevent to the timing. Change the points setting, and you change the timing a little. Reset the points to the right gap, then play with the timing.Only move it a cople of degrees at a time. I think you will find a place where all will be happy...
If it stumbles as you give it gas, you need to advance the timing a little....
 

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The distributor shaft housing that lifts the points might be a little worn...not a problem though.
 

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The advice posted by others here is all good.

Another thing you might look into is the condition of the coil. A weak coil will not produce enough juice to arc across a wider gap.
 

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A worn distributor plate assembly holding the points can give similar symptoms. Check to see if you have side movement on the upper distributor plate perpendicular to the direction of the pull of the vacumn advance. The wear would be in the pivot pin opposite the breaker points. Use a screwdriver wedged between the upper plate and distributor wall. Use light pressure on the screwdriver to see if the pivot pin has slack or wear. Excessive wear would be more than .010" movement or visually seeing the pivot pin wobble.
 

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In addition to moving the initial advance setting, for which you compensated, the point setting affects the dwell. Some cars, Lolita is one, like a little more or less dwell than the book calls for. This can be quite confusing to figure out when the distributor's point cam is worn down a ways. This affects how much dwell a given point setting produces. Don't worry about it - you found a setting that works !
 
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