Moparts Tech Archive
MP timing chain sprocket: Anyone know what the multiple marks are?
Got a question on the Mopar Performance Parts #P4452770 timing chain sprocket: Does anyone know what the multiple marks are on the crank sprocket? There is the standard "O", but then there are two others. The sprocket also has three "key" slots as this is a 440 and the crank sprocket uses a key. Are these used to adjust timing, or help get better alignment with the Cam sprocket? Thanks Dave
What are the other 2 marks? Depending on who it is made by, they could be an A and an R, a triangle and a box and there is one other I have seen but cant remember what it was.
Each keway corresponds to one of thos marks. If you put the gear on with the O keyway, you use the O timing mark. This is theoretically heads up, if you want to advance the cam, you use the A keyway and the A mark, this will advance the cam, same for retarding it.
The 'dots' are for a strait-up or the installed center line of the cam.
The other two are for 4 degrees advanced and 4 degrees retard settings.
believe they were a triangle and a box. Do you happen to know which one is advanced and which one is retarded? I didn't get any information with it.
If Im not mistaken, the triangle is advance.
You can check for yourself. Put the gears on at the O, or heads up, now take off the crank gear and go to the triangle marking. If you have to turn the crank backward to line the marks back up, that is advance, if you have to turn it forward to line them up it is retard.