Cam Timing with Supercharger
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From: CA/WA
Lets get this straightened out so we can install it right on Thursday!
We have confirmed to do the run on Thursday! I'd like to work out this confusion before I head over to DO!
- Sung
EDIT: so I think I read over this more than 20 time. Each time I read it, it makes sense, and then I see a different way. I am totally confused now.
I have dug up this response from sideways:
Your questions: I think the exhaust cam rotates clockwise, correct? So advancing it two degrees makes it a little further in a clockwise direction at TDC than it would be stock?
Not correct.
From the front of the engine, both cams turn counter clockwise.
The cam should move counter clockwise in relation to the sprocket to advance and clockwise to retard.
The cam timing will look stock with the key advancing or retarding the cam 2 degrees in relation to the sprocket.
Not correct.
From the front of the engine, both cams turn counter clockwise.
The cam should move counter clockwise in relation to the sprocket to advance and clockwise to retard.
The cam timing will look stock with the key advancing or retarding the cam 2 degrees in relation to the sprocket.
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Heres a link on cam timing from turbo magazine.
http://www.turbomagazine.com/tech/tu...s/viewall.html
http://www.turbomagazine.com/tech/tu...s/viewall.html
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From: CA/WA
Put both marks even and work the exh cam first. Put the key in if the mark goes backward then you retarded it if it goes forward then is contrary. Les overlapping means the exh cam retarded a bit. It is supposed to shift the powerband to the left in the graph and increase power lower in the range. More overlap on NA does contrary les power down low more up top.
- Sung
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From: South of the pier, Huntington Beach, CA
The cam key does the same thing in a fixed amount.
The red part is fixed to the cam. See the scale at the top of the red section.
A slight movement of the cam counterclockwise while holding the black section of the sprocket fixed will give cam advance. Note the little A on the scale.
The opposite direction is retarding the cam timing. Since your shop guy is following this thread ask him if he understands clearly.
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From: CA/WA
Originally Posted by S2SEXY' timestamp='1324345352' post='21249599
close up of a cam gear.so if you spin the center section to the left it will put that scale in advance.The cam key does the same thing in a fixed amount.
The red part is fixed to the cam. See the scale at the top of the red section.
A slight movement of the cam counterclockwise while holding the black section of the sprocket fixed will give cam advance. Note the little A on the scale.
The opposite direction is retarding the cam timing. Since your shop guy is following this thread ask him if he understands clearly.
Looking at this picture again,
putting the keys on the exhaust side in such a way will make the cams go clockwise, thus retarding exhaust side. In same principle, the key on the intake side will make the cam gear turn counter-clockwise, advancing the exhaust.
So basically, the diagram that has been drawn and agreed upon is wrong? Let me know if you are following it.
- Sung
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From: CA/WA
Damn.. okay.. looked at the forum again.
The drawing and the orientation of the keys is correct.
The degree number imprint is on the left side of the key when advancing and on the right when you want to retard.
And then I looked at the keys. The drawing matches how the keys are supposed to go. I thought the top part of the key is the offset. Misunderstanding on my part.
So, JUST in case they stopped following this thread, I will be taking these photos in:
In addition, I will probably give them a call tomorrow and email them the 2nd picture, making sure they understand and agree.
Any1 see any corrections I should make?
- Sung
Offset moves the cam in relation to the cam gear. The lower part of the key is the offset. In the diagram above on the exhaust the lower part is offset to the left thus advancing the exhaust cam. On the intake side the lower part of the key is offset to the right thus retarding the cam. Both cams turn left (counterclockwise.)
The degree number imprint is on the left side of the key when advancing and on the right when you want to retard.
So, JUST in case they stopped following this thread, I will be taking these photos in:
In addition, I will probably give them a call tomorrow and email them the 2nd picture, making sure they understand and agree.
Any1 see any corrections I should make?
- Sung