[DefiantGSR]

recently, MD had a long post w/ pictures that explained how to degree a cam. i tried searching but couldn't find it. anyone link me? or care to explain again? haha

 

[DefiantGSR]

ahhh, found it

 

[MichaelDelaney]

shortened explanation:

To degree the cam, you do the following:

Install a degree wheel on the crank. Find TDC, adjust the degree wheel to zero. If you really take this serious, and you do if you want to degree your cam, finding TDC means setting up a dial indicator on the cylinder block with the head removed, and rotate the crank until the piston is 1" (25 mm) from top on it's way up. Note the reading on the degree wheel. Rotate further until the piston is in the same position on the way down. Note the reading as well. TDC - the REAL TDC is just in the middle between these two readings. (Edited by MD: You can do this without having the head off .) Now compare that to the "T" marks on the ignition advancer. If its correct, you're lucky, if not, correct the mark.

Assemble the top end but leave off the valve cover. Set up a dial indicator on a intake valve, set it to zero with the valve closed. Rotate the crank until the valve is .040" (1 mm) open. Note the reading from the degree wheel (OPEN). Further rotate the crank until it is 1mm from closing. Note the reading at the degree wheel as well (CLOSE). Lobe center for the intake is:

[(OPEN - CLOSE)]/2 + 90


Do the same for the exhaust valve. Lobe center for the exhaust is

[(CLOSE - OPEN)/2 ] + 90


If these values differ from what the cam manufacturer says, adjust the cam sprocket until the LCs match the specs. If you do not have specs from the manufacturer, adjust the cam to be symmetric, i.e. identical lobe centers for intake and exhaust.

 

[MichaelDelaney]

You need to know cam specs in terms of lobe centers.

The Honda Service Manual or Cam manufacturer will give these timing specs @ 1mm (0.04 in.) or @ 0.05 in. on your cam's spec sheets:

Intake Opens ___ degrees btdc, Closes ____ degrees abdc

Exhaust opens ____ degrees bbdc, Closes ____ degrees atdc





You need to place the valve lift indicator onto the cylinder #1 valve and find the degree reading on your wheel at zero lift and at the 1mm or 0.05 in. lift point to locate your lobe centerlines (assuming you have correctly followed the steps to find TRUE TDC which is the critical accurate step in all of this).

This is why I gave you guys this article, awhile back...it was meant for the more advanced guys here who are going to do their own degreeing after installing their cams.

To turn the crank, I remove the driver's side wheel and access the crank there using a crank extension (that you should buy and own anyway) for your socket wrench.

You don't have to use those massive degree wheels the domestics use. Motorcycle cam degreeing kits use a smaller degree wheel and works great in our cramped engine bays.

 

[Gvtec]

I was wondering how those 5" degree wheels worked in such a small place. I'll have to check those cycle units out.