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Dot to Dot is going to get you in the ball park. Just make sure to line them up before taking things apart, then don't disturb the engine. Sometimes dot to dot is #1, other times #6. It doesn't matter which as long as it goes together the same as it came apart.
The Feather and Lite used the MP 244 cam. It was the "Marine Cam" prior to 1971, then became the OEM stock mechanical cam up until the hydraulic engines became standard. The stock cam that came in these cars is excellent.
Other good choices for a a cam would be the Erson RV10M, the RV15M, and a special RV15M RDP designed by Doug Dutra. Erson will do custom grinds to order, as will comp cams and many others. Some folks have found issues with Comp Cams blanks where the timed oiling passage doesn't match up to the cam bearing passages. There are methods for fixing this. It's a darn good idea to check in any event! If the passage isn't properly alligned, there will be top end oiling issues.
I haven't heard of any issues with the OEM or Erson offerings.
I run the Erson RV15M RDP straight up. It is actually advanced about 3° from the cam card, which matches up to the regular RV15M rather than the RDP lobe center. The cam in question carries 110° lobe centers.
Degreeing in requires a degree wheel. You will need a piston stop, or preferrably, head removal, which is the best way to do it. Once top dead center has been identified, and the degree wheel set, a dial indicator is placed on the intake lifter to determine when the cam event is occuring at .050" lobe Lift. This is easiest to do with a "Special" Tall Lifter that can be built with a flat upper face to indicate to.
Finding top dead center will also allow you to mark the balancer accurately if the outer ring has slipped. This is common, and a lot of folks end up setting timing based on a mark that is in the wrong place.
It is more difficult to do with the head on, but not impossible. It is important that valve train Geometry is correct. Varying thickness head gaskets and any head or deck cuts can change the angle of the pushrod, and thereby the amount of measured lift at the pushrod end of the rocker. Affixing the indicating device is also harder with the head on, depending on the type of indicator base you have available.
The reason degreeing the cam is important is there are variations in manufacturing of the timing sets, and to an extent, the accuracy of the cam grind. When buying a timing set, stick with good stuff, not bargain. Melling is "Good Stuff." A double row timing set can be used to improve accuracy, but there are oiling issues that need to be addressed. You can also go to a true roller chain setup, but they are very expensive, and not really needed for the engine speeds most slant sixes see. Make note of how everything comes off with the timing set. There is an oil deflector that is important to avoid flooding the front seal.
While some folks seem to think nothing of driving the lower timing set gear onto the crank, I strictly install with an installation tool. I don't like beating the snot out of my thrust bearings.
To test the timing chain to see if it's part of the problem, pull the cap and rotate the engine by hand till the rotor starts to turn. Stop, note where the crank is in reference to the timing mark, then rotate the engine the other direction. The rotor should start moving immediately. If you have to rotate the crank very far before the rotor starts to move, the chain is shot.
One of the most important tune up evolutions with the slant six is valve lash. If you find excessive noise, or more often, an exhaust miss, the lash likely needs to be addressed. As the lash tightens up, you will have a miss, and vacuum will not be good. Lash can be set static to start with, but to obtain best results, should be done with the engine running and up to full temperature.
Once you have a handle on setting to factory spec, there are further fine tuning methods that can be used to obtain best results. We can go into that later if you wish.
CJ
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