Need help degreeing a cam

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DartFred

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I degreed in my cam a couple weeks ago and found the intake centerline at 107.5 degrees instead of 110, so I ordered a 2* offset cam key from mr.gasket (987g) to bring it closer to 110 ICL. Since 2* at the cam = 4* at the crank, is this offset cam key bring me to 111.5 ICL or will it move it a true 2 degrees to 109.5 ICL (where I want it to be)? I also have an adjustable crank sprocket with 3 keyways (-4*, straight and +4*), this is why I ordered the 2* offset cam key. I'm kind of confused...

I can always borrow the dial indicator from work but I'm off for 5 days.
 
I would have left it at 107.5....a few degree advanced.
 
If it's a 2° cam key, it will move the cam 2° in the direction of the offset. When measured on the crank with the degree wheel, it will indicate a 4° change because the cam moves 360° to the crank's 720° (cam turns at 1/2 speed of crank). so move the crank 4°, cam will move 2°. If your timing set has three possible positions take a look at it. If you have a 4° retarded crank keyway you can just use that with the straight up cam key you'll be at 109.5.
 
moper said:
If it's a 2° cam key, it will move the cam 2° in the direction of the offset. When measured on the crank with the degree wheel, it will indicate a 4° change because the cam moves 360° to the crank's 720° (cam turns at 1/2 speed of crank). so move the crank 4°, cam will move 2°. If your timing set has three possible positions take a look at it. If you have a 4° retarded crank keyway you can just use that with the straight up cam key you'll be at 109.5.
Click to expand...

If I use the 4* retard keyway on the crank, wouldn't that bring me to 111.5*? It would have the same effect has using the offset cam key. I think I will try both to see which method brings me closer to 110 (there might be a slight difference because of manufacturing...)

Is 107.5* too advanced for a 114 lsa cam?
 
moper said:
If it's a 2° cam key, it will move the cam 2° in the direction of the offset. When measured on the crank with the degree wheel, it will indicate a 4° change because the cam moves 360° to the crank's 720° (cam turns at 1/2 speed of crank). so move the crank 4°, cam will move 2°. If your timing set has three possible positions take a look at it. If you have a 4° retarded crank keyway you can just use that with the straight up cam key you'll be at 109.5.
Click to expand...

Dave I agree that moving the crank 4* moves the cam 2* but since all measurements are taken off the crank I believe moving it 4* would put him at 111.5*, wouldn't it? I've degree'd in several cams and every timing set I've had that was stamped 4* moved the reading 4*.

DartFred, moving it that much (to 107.5*) IMO is a little too much. I don't like to move them over 4* max but that's my personal preference. It doesn't take long to change it to the 4* setting on the crank key so you might try it to verify what happens and let us know.
 
fishy68 said:
Dave I agree that moving the crank 4* moves the cam 2* but since all measurements are taken off the crank I believe moving it 4* would put him at 111.5*, wouldn't it? I've degree'd in several cams and every timing set I've had that was stamped 4* moved the reading 4*.

DartFred, moving it that much (to 107.5*) IMO is a little too much. I don't like to move them over 4* max but that's my personal preference. It doesn't take long to change it to the 4* setting on the crank key so you might try it to verify what happens and let us know.
Click to expand...

I'm with Fishy on this one. Cam timing advance or retard is measured in crank degrees.
 
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