Tachometer reading

IvaTiger

IvaTiger

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After a full rebuild of the original engine and a total overhaul of the whole car, I finally put power to the electrics of the car I have still to attach the rebuild Holley 265cfm 4 barrel and fuel the car up. The oil pressure gauge came up to 60 plus psi when cranking the engine.
So it looks like everything is connected correctly with all the lights horns etc working
My question is would the tachometer give a reading in cranking mode or does it only show a reading with the engine in run mode ?
Thanks
 
I've seen module controlled dizzy cause the tach to be a bit twitchy until it gets a consistent signal once running. It's a sometimes thing and not an issue.
 
Sunbeam Specialties sells a Pertronix Ignitor (page 17) that replaces points in the distributor. Will my stock tachometer work with this or is some additional work needed?
 
floyd landis said:
Sunbeam Specialties sells a Pertronix Ignitor (page 17) that replaces points in the distributor. Will my stock tachometer work with this or is some additional work needed?
Click to expand...
I installed one of these and it affected the reading a small amount. The tach is adjustable. I can walk you through that if you end up needing to do it.

Some things to keep in mind with the pertronix unit. You MUST use aramid/carbon core spark plug leads. Running stranded metal core wires can burn out the amplifier in the unit. If you decide to use the pertronix coil you will need to delete the OE ballast restistor as the pertronix coil is internally ballasted, an additional ballast will cause the voltage to be too low. You should also expect to have to reset your ignition timing as installing the pertronix unit will throw the timing way off.

I ended up not being really happy with the conversion and went back to points. If it breaks down on the road, you're calling for a tow, or reinstalling the points to get going again. points are cheap!
 
I am certainly not "up" on the current offerings from Pertronix.
But ten years ago I was.

They offered 3 different models, the Ignitor 1, 2 & 3. I ran them all. Each required a different coil resistance. (3 ohms, 1.5 ohms 1/3 ohm?) Back then using an Ignitor 1 with a coil meant for a 2 or 3 would fry the Ignitor unit, as could also happen if a key had accidently been left on.

I was never happy with the 1. The 2 was fine and could rev to 6K or maybe a bit higher. The 3 could rev to 8K and higher all day and even had a built-in rev limiter (that was a pain to set but worked fine).

I spent a lot of time back then with Pertronix support and engineers and was impressed at how dedicated they were to improving their products. I'm sure the products are better now.

But I'd still recommend being careful about using a coil from a higher series.

Floyd, unfortunately I was using a non-stock tach so I can't answer your queston. But I can tell you that the non-stock tach did have issues with Petronix that Support helped us fix.

Buck
 
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Iirc there was several threads in the tiger mailing list about adding a resistor for the tach when using a petronix... Sometimes the tach would only read to a few thousand rpm or jump around...
 
Standard ballast resistance in either Tiger or Alpine is 1.6 ohms. Both used unballasted coils. The Alpine uses a Lucas coil and Lucas ballast, and the Tiger used a Ford coil and 57 T-bird ballast. The same coil was used on all 60's Ford products. '60's vintage Fords used a ballasted feed wire from the ignition to the coil and as such, dispensed with a separate ballast resistor.

The instructions for the Pertronix "drop in" unit suggested a matched "internally ballasted" coil and removing the separate ballast resistor from the ignition circuit. I found that the electronic ignition would work with either the stock Ford coil and ballast or with a Pertronix coil and no ballast but I had a weird ignition miss between 2-3000 RPM that I couldn't resolve. The tach worked just fine with no modification, but I did have to reset the timing with the Pertronix unit installed.

The instructions with the unit did not specify the type of spark plug leads, but their online instructions did. Aramid/carbon core wires MUST be used, solid core wires will damage the amplifer leading to total ignition failure. In the end, I removed the Pertronix unit and refit the points and have been completely trouble free since.
 
The Pertronix and most other basic points-replacement coil drivers (i.e. not MSD or other multi-spark units) still work in exactly the same way as the original points did. There is a sensor that reads the distributor shaft position, and it turns on and off the current to the coil. So theoretically you could use any coil and ballast combination that you would use with points, but the reality is that the silicon internals of the coil driver may not be as robust as the copper and steel slugs that make up the points arrangement. Hence Pertronix’s recommendations to use particular coil/ballast combinations and radio suppression plug wires.
The Tiger tachometer’s coil-current detection circuit was designed for typical points type dwell angles, and it does not always work properly with the high dwell typically generated by the electronic coil drivers.
 
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