Advancing crankshaft to camshaft timing

recently I installed a Lunati 703 cam into 383. Instructions said to install at 106* centerline because cam was already advanced 4*. Did the degreeing of the cam 3x and always came up at 107*. Checked with Lunati and they said that was close enough, however, he would advance it 2*. Since this was my 1st venture into this kind of replacement I left it at 107* and buttoned it up. Did the proper break-in procedure and everything was fine. I find myself at this time with the chain cover off to fix an oil leak problem, my fault. I had also changed the timing chain and sprockets and the crankshaft sprocket is a 9 position item. Originally I set it up for 0 advance/retard. My question is: Do you think it would be safe to just advance the cam the 2* now. After reading the instructions I learned that the crank would have to be advanced to the 4* slot in order for the cam to be advanced 2*. Of course the cam sprocket timing mark would have to line up with the 4A tooth on the crank sprocket. Since the center line is now 107*, this would only change it to 105* center line. Do you think that this is safe to do? All these replacement parts are only about 100 miles old. I have read that slight " advance " adjustments can be beneficial to a cam in the low end rpms. Thanks in advance for your replies.

Holy Schmokes.
If it currently is as it was, at 107- zero on the 9 keyway.
then put it to the 2 degree adv position.
Start with the crank at tdc, you will have to move the cam pin slightly, and put er back on.
Should be 2- 2* positions on crank gear. inner and outer

The cam has 4 degrees of ground in advance which is designed to compensate for chain stretch etc.
If you have plenty of piston to valve clearance another 2 degrees should be no problem.
The change will also raise the dynamic compression ratio because the intake valve is closing earlier. If you have high compression you should be mindful of detonation.

RemCharger said:

Holy Schmokes.
If it currently is as it was, at 107- zero on the 9 keyway.
then put it to the 2 degree adv position.
Start with the crank at tdc, you will have to move the cam pin slightly, and put er back on.
Should be 2- 2* positions on crank gear. inner and outer

Click to expand...

y Remcharger I'm using these instructions which state that 4* degrees of crankshaft advance, gives you 2* of cam advance. Cam advances at 1/2 distance of crankshaft, that's why the sprockets are different sizes. I think?

I've never seen instructions worded that way, but yes I agree, the 4* setting should make 2* advance cam timing. And if you had lots of v/p clearance - should fit no problem.

Never, EVER, trust the markings on a chain set... EVER... If you are going to move it verify that your cam is in the proper position with a degree wheel again.

Thanks Crackedback, I planned on doing that tomorrow and will let everyone know how it worked out. I already have moved it to the A4* mark and have chains and sprockets installed.

After reviewing the procedure for degreeing cam, I decided that the possible benefit of a 2* cam advance was not worth the task. Installing checking springs and solid lifter to make measurements is just going too far for little return. I repositioned sprockets for 0 advance/retard. As stated in post #1, this was a 107* center line vs 106* target. Close enough. Had to use 9" degree wheel because engine in car, so that and my 73 year old eyes are not going to be exactly spot on absolute accurate anyway. Thank You all for your input.