Originally Posted by billla

Hopefully you're pre-oiling the engine before dropping the distributor.

Bring the engine to TDC #1 compression by the timing marks. Make sure it's the compression stroke on #1 by holding your finger over the #1 plug hole and feeling the compression "burp" past your finger.

Rotate the engine back to about 12-16 BTDC by the timing marks. The engine will *not* start or run at TDC.

Align the oil pump intermediate shaft with the #5 intake pushrod using a big screwdriver. Mark the center of the #1 tower on the distributor body and drop the distributor so that the center of the rotor points directly at the mark on the distributor body. You'll have to start the rotor behind (counter-clockwise) a few inches and try a couple of times before it drops...but it'll work and things will generally line up

Ideally you've also filled the bowl of the carb with fuel so it fires right off.

Double, double check the firing order and everything else you can think of. A little time spent here can save you a lot of time later.

Finally, be sure you're using the right oil and/or oil + break-in additive.

I'm sure it'll go great - post pics

Originally Posted by billla

I generally change oil and filter right after break-in, then again at 500, 1000 and 3,000 miles - then at whatever your regular change interval is.

Originally Posted by rsteenwyk

...how do I set engine timing since there is no way to use a timing light during cam break-in...

Originally Posted by Honker

I usually have the timing light all connected (#1 spark plug) as well a vacuum gauge. The positve power cable on the timing light can be connected after starting. It only takes a minute to set the timing. Get the engine started, set the timing with the light, and do your 20 min. run. While doing the run, check for leaks, adjust vacuum, etc. I also usually vary engine speed a little several times during the run.

Originally Posted by longbros

If they did not do it when they were new, why do we have to do this now with a new cam and lifters?

Originally Posted by Danish Shark

Hmmm what happened to the old school method of setting the static timing with a regular 12V light bulb?
That's how I do it when I've had the distributor out.

Originally Posted by longbros

I am going to ask this question again. What did they do when these cars were originally built? Did they run in the cams at 2000-2500rpm on the assembly line? I can't imagine that. If they did not do it when they were new, why do we have to do this now with a new cam and lifters?

Originally Posted by daanbc

I'm going with your thinking. I do not believe EVERY motor was started up and ran 25 min. at 2000-2500 RPM. I doubt they even do this today. I believe (and soon will find out for myself) that if you add enough ZDDP, you'll be fine to go take the car for a 25 min run at different rpms. Just can't imagine every single motor ever built had gone though those steps...

Originally Posted by daanbc

I'm going with your thinking. I do not believe EVERY motor was started up and ran 25 min. at 2000-2500 RPM. I doubt they even do this today. I believe (and soon will find out for myself) that if you add enough ZDDP, you'll be fine to go take the car for a 25 min run at different rpms. Just can't imagine every single motor ever built had gone though those steps...

Originally Posted by 63mako

A lot of you are missing the real issue. Reduced Hydraulic intensity numbers are the main reason more cams are failing. A roller cam can have a fast ramp as shown in the graph above. Actually a better graph would have the duration @ .050 aligned and the area above the curve and lift would show up much higher in the roller cam. Modern cam designers are trying to achieve a profile close to a roller cam on a flat tappet cam because of the advantages in power, off idle response, broader torque curve, better vacuum. This requires a faster ramp. I have read a couple articles about this, one by Harvey Crane, the other by David Vizard. While neither one really points the finger at this David Vizard does reference that this is an issue. If you want roller cam performance use one. If you want to use a flat tappet check the duration @ .050 against the advertised duration. Factory flat tappet cams had a hydraulic intensity of around 70. If the duration @ .050 was 230 the advertised duration would be around 300. Modern profiles are much steeper ramps to give you the above noted advantages. David Vizard says that a hydraulic intensity of 50 to 55 is the smallest recommended "safe" intensity for a flat tappet. The Voodoo cam the OP referenced has a duration @ .050 of 241/245. The advertised duration is 284/292. This is a hydraulic intensity of 43. This is roller cam intensity in a flat tappet. This is beyond a safely engineered hydraulic intensity. I am not picking on Lunati. All the manufacturers are designing these type of lobes. They have to compete. The customer wants it, they build it. This combined with lower zinc levels in oil. improper break in, incorrect spring pressures, bad geometry and the customers using that new power has lead to the failures you are seeing. Actually the cam cores of today are far superior to the originals in the C3.

http://www.harveycrane.com/duration.htm

http://www.enginebuildermag.com/Arti...r_failure.aspx

Originally Posted by daanbc

I'm going with your thinking. I do not believe EVERY motor was started up and ran 25 min. at 2000-2500 RPM. I doubt they even do this today. I believe (and soon will find out for myself) that if you add enough ZDDP, you'll be fine to go take the car for a 25 min run at different rpms. Just can't imagine every single motor ever built had gone though those steps...

Originally Posted by 63mako

Flat tappet cams disappered in the early 80's and, no they were not broken in at the factory. Oil had 1200 PPM ZDDP. Spring pressures were low, ramp rates were rediculously lazy and lift was limited. If you decide to break in your modern aftermarket cam as you point out above you will more than likely not make it home without wiping a lobe.
Check the link in the engine builder mag article below reguarding hydraulic intensity

Originally Posted by Steve2147

That is the correct way to do it. Billla's method is only an approximation intended to get you close enough to start it then use a light. When using a light isn't going to be practical you set by the static timing method.

Static timing is set by first following the directions posted above to get the dist in. Now bring it around to your timing marks again and stop the crank exactly where you want your initial timing set. Connect your 12v test light clip to the - post on the coil and stick the probe on a good ground. Push the dist clockwise so that you are early. Turn the key on the test light should be out. Pull the dist toward you and stop at the moment the test light comes on. The dist has just fired #1. You are within a degree or 2 of where the timing light will put you. This is easily adequate to run at rpm for your cam breakin.

Steve g

Originally Posted by longbros

This is what I am saying. I am installing a stock cam, with stock spring pressures which are pretty low. No crazy aftermarkt grind with wild ramp rates, etc. So, if I add 1200PPM of ZDDP and fire it up, it should be just fine.