Cam Advance Timing Chain 1973 460

[BigBird28]

Boy have I been busy! After struggling to get the timing right after installation of MSD ignition, I decided to tear the front of the engine down and do the timing chain. I have everything off now except the harmonic balancer and timing cover.

I understand that the 1973 460s had a 4 degree factory retard at the cam. I'd like to get rid of that and time it straight up but just want to make sure that my plan and research is accurate before I go for it.

My plan is to manually crank the engine to TDC. Once at TDC, remove the harmonic balancer and timing cover. I'll then remove the old timing chain.

I'm then thinking that next I fit the new crank gear onto the shaft in the keyway and line up the new cam gear to the 4 degree retard keyway slot. Then I'll slide the cam gear off and rotate the cam so the it lines up with the tdc 0 degree keyway on the cam gear. Thus this will advance the cam 4 degrees from factory to a straight up timing.

Do I have this right? I really want to be careful as to not destroy the engine and bend valves.

 

[74 Harley]

If you want straight up zero timing buy a stock replacement set for a 69 429. It's really easy as lining up the marks on the gears. Even the three position timing sets have a 0 setting. Don't trust the harmonic balancer to be 100 percent accurate. The outer ring can slip a little after so many years. You have no worries about bent valves, it's not an interference engine. Good luck, and ask any more questions you have!

 

[BigBird28]

If you want straight up zero timing buy a stock replacement set for a 69 429. It's really easy as lining up the marks on the gears. Even the three position timing sets have a 0 setting. Don't trust the harmonic balancer to be 100 percent accurate. The outer ring can slip a little after so many years. You have no worries about bent valves, it's not an interference engine. Good luck, and ask any more questions you have!

Ah yes thank you! I do have a new timing set with the three positions. So I'm planning to get the engine to TDC, then remove the old set and put the new one on. Once I have the new one on, I'll slip the cam gear off, and rotate the cam +4 degrees to the 0 degree position on the set. Definitely not going to be trusting the harmonic balancer and very good to know it's non-interference. I thought it was for some reason.

 

[74 Harley]

As far as cam timing goes it's pretty easy. As far as the settings go -4 gives more top end power, 4 advanced gives more low end and mid range power. -0- tries to be a balance between the two.
When installing the gears you have the crank gear with mark at 12:00, the cam at 6:00.
However, if your distributor is out you must roll the engine 1 turn so that the cam and crank are both at 12:00.
Otherwise your timing will be 180 out.

 

[BigBird28]

As far as cam timing goes it's pretty easy. As far as the settings go -4 gives more top end power, 4 advanced gives more low end and mid range power. -0- tries to be a balance between the two.
When installing the gears you have the crank gear with mark at 12:00, the cam at 6:00.
However, if your distributor is out you must roll the engine 1 turn so that the cam and crank are both at 12:00.
Otherwise your timing will be 180 out.

Got it! Right now I've got it almost completely torn down (half a day wasted trying to get the harmonic balancer off). I have the fuel pump eccentric out but I can get the cam gear to budge. Any ideas as to what may be holding it up or how I can pull it?

 

[74 Harley]

The cam gear should have 3 bolts, if those are out the you may need to GENTLY pry it off. What I have done is to put a large screwdriver on each side and work it back and forth. Sometimes they get stuck after so many years.