New Distributor Tester, Points, R1 R2, etc.

I haven't used this one yet but read some reviews which were favorable. It is quite compact compared to my Sun 404 and DT110 tester.

The problem with the Marelli adapters is that if it uses the mounting clamp as shown in the picture you have to remove the dog drive for testing the distributor, which is kind of a hassle. My 404 adapter uses the same approach unfortunately, for my DT110 i plan to have a mounting clamp which is wide enough to let me test the S1XX/SM805A series distributors without removing the dog drive.

It is safe to remove the R2 setup in a double S159A setup. If you have a S127 single distributor and the terminals are labeled "A" and "B" then leave everything wired as it is ;-)

 

It looks like a nice unit, but pretty pricey. I have an Allen, and made an adapter out of an aluminum pipe flange and a short length of pipe. For the drive I use a piece of flexible tubing and a piece of solid rod. My distributors have splined drive.

As for the R2 points, you can disconnect them. All they do is retard the spark by 5º at idle if set correctly. One of the things I have been experimenting with is to use the R2 points as a dwell extender. If you look at the circuit on an oscilloscope it basically puts out a square wave. The length of time the points are closed (the dwell) is when the coils are being charged. When the points open the field around the coil collapses, inducing a big jolt to fire the spark plugs. The points stay open for a while, possibly longer than necessary for complete field collapse in the coil. So, I've been setting the R2 points to close 5º before the R1 points close, thus extending the time the coils charge (dwell extension). The R2 points are also set to open just before the R1 points, because that is the critical timing point for ignition timing and is controlled by the R1 points in this setup.

If nothing else you could set the R2 points to close and open within the envelope of the R1 dwell to share the load with the R1 points.
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Or just put pertronix in your distributor and be done with points.....

 

still uses the mechanical advance.....

 

So, for those of you wanting to keep the points, you really don't need to spend $200.00+ on a custom machined Marelli adaptor. I used a 1952 Allen Syncrograph to check mine. I made a holder from an exhaust reducer flange that I had laying around from a prior hot rod project. The large end fit the casting under the dizzy and I brazed a fixing point to it. I had the splined shaft also, so a piece of brass tubing was used. The object is to hold the housing, and spin the shaft, nothing more. Worked perfectly.
Also, the dwell angle (amount of degrees or time the points are closed) is to charge the condensers, not the coil. The coil is nothing more than a voltage transformer. Here are some photos.
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Pertronix can have a timing variation of up to 4-5º between cylinders unfortunately, here is an alternative approach i did for my 308 (still based on the mechanical advance):
http://www.ferrarichat.com/forum/308-328/453748-bosch-ignition-s159-double-distributor-setups.html

That's perfect With the later S159B/C distributors you don't have that problem due to the spline drive, but the S159A for Europe still has the dog drive in place.

With the S159 coil and points setup the coil stores the energy, you were thinking of a capacitive ignition as in the 246GT?

 

Yes the Sun distributer machines are large, they fit nicely on a roll-a way- tool chest

 

The condensers (capacitors) are there for radio noise suppression generated when the points open and a small spark is generated (see Marconi spark-gap transmitter) at the points. The coils are step-up transformers that produce the 10-16 kV voltage spike that actually fires the plugs. When the points are closed the current in the primary coil generates a magnetic field that induces the voltage spike in the secondary winding when the points open and the field collapses.

In order for this inductance to be produced the magnetic field has to be moving. This movement is produced by the rapidly expanding field when the points are closed. The field collapses when the points open. That's why you set the points to OPEN at a certain time in reference to the crankshaft.

 

Exactly. Keep it stock or toss them completely.

 

Check your readings. I had done the same using a piece of fuel line, and though it was short, it actually twisted and gave me erratic dwell readings. I then went to the brass tube which worked better.

 

Liked your clip! This seems like a cool machine. One question: what the Max rev It can make? I not familiar with any of these setjes for testing But i guess you need quite a high rev to see the high rev area of the engine

 

Ingenious does a max of 5000 RPM, that's quite enough being 10K RPM at the crankshaft My Sun testers just do 3500 and 4000 RPM max, i tend to test up to a max of 3500 RPM camshaft/7000 RPM crankshaft.

Still pondering getting a ZVP1, they are really nice machines.

 

Me too!!