Timing question
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Lead Driver
Joined: Mar 2008
Posts: 7,188
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From: Near Los Angeles
Timing question
I'm a little baffled and was hoping for some clarification. Bare with me.
If the engine is at tdc compression stroke, and the rotation of the rotor is c.wise, and let's say the rotor is pointing at 1 o'clock. The #1 contact is just to the right of that. If I move the distributor c.clockwise I am advancing the timing, correct?
I guess this is where I am confused. If it is set up as above stated, I would think that if it fired say 10 in advance, then I want to believe the rotor should be at about 1:30, showing that it already fired before the piston reached its zenith.
I mean I have been timing cars for years but I have trouble understanding this relationship.
If the engine is at tdc compression stroke, and the rotation of the rotor is c.wise, and let's say the rotor is pointing at 1 o'clock. The #1 contact is just to the right of that. If I move the distributor c.clockwise I am advancing the timing, correct?
I guess this is where I am confused. If it is set up as above stated, I would think that if it fired say 10 in advance, then I want to believe the rotor should be at about 1:30, showing that it already fired before the piston reached its zenith.
I mean I have been timing cars for years but I have trouble understanding this relationship.
Postmaster
Joined: Mar 2005
Posts: 2,949
Likes: 6
From: Earth
The cam turns at 1/2 the speed of the crank, i.e. 360 degrees rotation of the rotor = 720 degrees crank rotation.
So at TDC running 10 degrees advance on the crank the rotor should be 5 degrees clockwise of the #1 terminal on the dizzy - 1/12th of the distance between the #1 and #5.
So at TDC running 10 degrees advance on the crank the rotor should be 5 degrees clockwise of the #1 terminal on the dizzy - 1/12th of the distance between the #1 and #5.
Laughing Gas
Joined: Nov 2003
Posts: 898
Likes: 1
From: southeren Oh
think of it this way if rotation is C clock wise when you turn it in the same direction you are trying to outrun the engine (retarding timing)
It turn (clockwise) to meet it early you advance timing.
It turn (clockwise) to meet it early you advance timing.
