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This'll be a little long.
Why GM decided to go with an integrally set of components was two-fold, first, techs and owners weren't replacing both the point set and condenser per maintenance cycle, so, making the condenser as a part of the points solved that issue, but caused a lot more. Second, in all automotive distributors, there is a slight air/oil vapor that exists above the upper bushing, that is from the bushing to shaft clearance, no seal, and even though there is vacuum inside the engine,m from the PCV< it isn't enough to get a bit of oil up and onto the points plate, points, condenser. When the heat gets to the oil, it makes a form of goo that doesn't allow good metal to metal connection, points/condenser to point plate, and the component screw threads. Adding the condenser to the points was a good deal as far as eliminating the loss of ground continuity between one of the components and points plate/ground.
That didn't work well, as the condenser wasn't grounded well to the points, and the whole mess to the points plate. All this changed the resistance values in the system past the ballast resistor, changing the load on the condenser, which helped carbon the point faces up quicker than the separate pairing. Going back to the two component system, and making sure the points plate was clean of oil residue, and making sure it was grounded to the distributor body was the best way to go for point setups.
A bit if facts about points.
Points faces should NEVER be "dressed" (sanded, filed), EVER. Why? the actual contact faces are tungsten coated, to help resist points materials degradation. The face materiakl itself is very prone to building up carbon.
The other contaminants inside the chamber cause loss of grounding stability, change resistance by increasing the components to point plate, and ground clenliness. This causes more load and heat on the contact faces, and if the tungsten is removed, the carbon buildup and materials transfer gets faster, exponentially.
Points that have had the tungsten removed are prone to lower the continuity of the faces, which lowers system amperage output to the points.
Remember, a point ignition set will only make what is needed to bridge a REASONABLE spark plug gap, if dirty, the system makes less spark energy.
"Create a spec". What the daylights is that? Well, for points in systems like the S and H1B, it means easier timing readjustment after the hard part of setting it up the first time. I use a regular battery operated car rpm/dwell meter and a non-dial back timing light, along with my dial indicator, creating a dwell spec for the points, and individual timing marks for each cylinder, so I can use my timing light.
First, I use the dial indicator to set each timing line, qualified to be accurate to use my timing light.
Then, I take new points and mount them, and set them all at .016 (they can be set to any distance specified). I connect the dwell meter and timing light, fire the engine up, and read the dwell, with the meter at 8 cylinders (it can be done with 6, 4 setting). The rest is common math. Assuming 220 degrees on the 8 scale, divide by the number of cylinders the meter is reading, 8. 220 divided by 8 = 27.50 degrees. You have now created a specification for individual dwell meter setting for each set of points. Record this specification you have just created for future use.
Now, engine at idle, set all the dwells at 27.5, or round it off, 17, 18, whatever you feel is best.
Set the timing with the timing light. As you are adjusting the timing with the slider bracket for a set of points, the dwell might change, simply work with it to end up with the same dwell and timing correct, done. Go to the next set of points.
The silver lining in all this is, it takes more than a short time to get this all set up and adjusted correctly. BUT, once done, dwell and timing set correctly, when it comes time to check and reset timing, all that needs to be done is one of two functions, simply readjust the points to get your create a spec dwell setting, leaving the timing slider in place, not changed, and the timing will be dead on again, OR, connect the timing light up, adjust the points ONLY, until the timing marks align on the set, not changing the slider for timing, done. The points dell will be back on your setting.
The big hassle is creating a specification, and getting the whole mess set up in the first place, but once done right, setting timing becomes a really simple operation.
Why not use the dial back feature on the timing light?? Well, our points setups are not set to have a computer lag in the timing configuration, the dial back is a response to the time it takes for an EFI computer that computes timing to do so, as the computer will be off proper timing with a "lag". Point systems do not create a computation lag, so, no lag to recover a reverse lag that isn't there needed in the timing light. Our DC systems also go not have a computation lag, so, no dial back on H series CDI systems.
Yeah, I did this stuff too, along with working on race bikes. I gave my website above, shows what I developed, the small-body HEI for car point type distributors, so they fit, and not hit firewalls.
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