What does that mean, it "appears" to be correct? Did you actually check, or not? Not trying to beat up on you here, this is important though.

You have to measure, don't guess! I'm a card carrying member of the guess-and-by-golly method of tuning at times, because it is at times just as much an art as a science - though not, not never, when setting the baseline! Use a piston stop tool. What that does, is physically determines the actual no-&@$% mechanical TDC point of the #1 piston on the compression stroke.

Everything related to ignition timing and camshaft phasing - valve opening and closing events - is based upon this point being correctly marked on the balancer or damper. Then, bounce the true, known TDC point achieved by this method against the "0" mark indicated on the balancer pointer and compare. Are they perfectly aligned? Off 2°? Or off 20°?

It is a simple thing, but it looms large downstream, because it is so common for older, high mileage balancers to be defective due to their age.


OK. Now here's the next thing about measuring engine manifold vacuum for diagnostic purposes. All of the "rules of thumb" and the charts, diagrams etc., about what is "normal" chiefly apply to OEM stock engines at sea level. And - at OEM factory base ignition timing settings. Typically this might be something like 3° or 4° or maybe 6° BTDC.

It's well known that most engines "like" 12° or 14° of initial ignition timing, or even more, and of course you can set the timing wherever you like, but for diagnostic purposes when making a determination of mechanical engine health it's important to actually measure the manifold vacuum at the factory settings. The reason for this is because the factory manifold vacuum specs listed in the manual were measured and determined under these same conditions. If the camshaft has been changed, this complicates things. Also if you live at high elevation, a correction factor is applied. All this has to be taken into account to make a determination of what is "normal".

Set the base ignition timing to an accurate known 6° BTDC, RPM to 500. What is the engine manifold vacuum now?

If normal manifold vacuum numbers of 19"- 21" cannot be achieved without advancing the timing excessively it indicates a defect, possibly a stretched or worn timing chain, for example. Engine vacuum levels are almost directly related to base ignition timing, so again for accurate diagnostics they must be checked at the factory ignition timing listed in the shop manual. If the vacuum test checks out normal then you can continue on with the Tune-Up, and set the timing wherever you want. If it doesn't check out normal, stop, find out why, because it will never run quite right and can't be made to run quite right.

Misfire: It sounds stupid but you might be surprised just how often previous owners or mechanics get spark plug wire firing order wrong. If two plug wires are swapped around the engine will sometimes seem to idle reasonably well, though the power under load will be down considerable. Be sure to check for this.

It appears that you have the Pertronix Ignitor I which is a bare-bones point replacement module. There's nothing "wrong" with that, but it requires a minimum 1.5 ohms primary circuit resistance so it doesn't burn up due to high current/voltage. If the ignition coil will handle a constant "12 volts" so will the Ignitor module - provided the 1.5 ohm minimum primary circuit resistance is observed. They tend to be more reliable with ~ 12 to 14 volts versus 8 to 9, but excessive current (amperes) will roast them in short order.

 

The way your truck (1966) is OEM wired is both points and coil are fed reduced VOLT through a resistor wire off the IGN SW. There is a by-pass circuit in START that delivers full BAT VOLT to the IGN to ensure it receives enough voltage when cranking for a fast start due to VOLT DROP @ the starter and harness (resistance).

The IGN I requires MODULE full BAT VOLT to perform correctly. The coil you have chosen (MSD 8222) calls for an external resistor (9V. Coils are available that do not require a resistor and will give a hotter spark

That is a BAT relay/fused circuit that by-passes the IGN SW circuit to achieve a more reliable voltage source and negates the resistance of an old IGN SW and harness circuit

You are referencing PERTRONIX PN 1281 INST SHEET, correct?

1ST CIRCUIT From IGN SW via resistor wire/ballast resistor -

See How The POINTS-MODULE are powered? The coil has it's own separate feed.

2ND CIRCUIT Shows Resistor Circuit For IGN MODULE and EXTERNALLY RESISTOR style coil.

Yours will be similar to NO. 2 but the MODULE will be 12V whereas the COIL will be 9V.

BTW- The IGN I is an older system Read the warnings in the instruction sheet.







.

 

I don't have the instruction for the Pertronix unit.
What I'm taking away from this is that using the Pertronix module I should bypass the ballast resistor and using their relay run 12 V into the Pertronix and coil? Running the coil on 12V as possessed to 9 should result in a hotter spark and make full use of the MSD coil 45k spark capacity. Since the Pertronix is powered off the + side of the coil it will get the 12 V it wants.

Is that a valid take-away? If so I'll order their relay kit. https://pertronix.com/pertronix-2001...ription_tabbed

Thanks

 

TDC #1 matches the dampener, me and my wooden dowel rod verified that.
I got down under the front of the truck with a very bright light, a magnifier glass and a white paint marker. I was able to find 10, 20 and 30 degree markings and marked them. The mark the PO had created is the 0 mark.
I had guessed at the 14 degree timing previously. Now that I could better see what was happening I set the initial timing to 10 BTDC and it runs better now. Feels more tourquey and I can get the idle down to 400. I haven't put the vac gauge back on it but the misfire isn't noticeable and the surging I was getting at low speed is gone.
Finally steps in the right direction. I have 10 degree initial, and a total advance revving the thing of about 30 degrees.

I need to get the Pertronix and ballast resister thing sorted out but with all the help and suggestions here on the board I'm feeling better about the issue.

The MSD coil lists a "Primary Resistance: 0.700 ohms" - Looks like that is a NO-GO there? Here is the coil. https://www.summitracing.com/parts/msd-8222

Thanks!

 

OK, the way your truck is wired, the RELAY KIT will be the easiest way out. It will power the IGN I module only..

The coil is external resistor (unless used with an MSD box) and will work directly off your old coil power wire and you posted it was reduced VOLT on RUN, correct?.

I called HOLLEY HOTLINE as it is confusing to me also. You are mixing two different manufacturers and they don't seem to want to share info to inter-use it seems.

If all would ID the coil type, it would make it a lot easier. But again, they want you to use their product(s) exclusively.

 

There you go. It gets 12V while cranking and 9V (approx) in RUN.

 

Pertronix said the MSD coil is a no-go. In order to use their relay for the coils and the Ingitor I need a integrated resistor coil like their Flamethrower.
I like the idea of a simpler wiring setup. Get their relay and their coil so I don't have to run the low voltage ballast wire to the coil; and a different 12V to the ignitor. I'll have a garage sale on coils when I'm done Maybe Summit will let me exchange their slightly used MSD coil.

Update: Just checked their return policy and nope, no used parts can be returned.

 

Their reasoning is sound, but yes, you can use the IGN I and the MSD coil together.They want to sell you the proper coil.

I was going to suggest that but I don't know how much money you have in it now.

It is always a good idea to stay with one supplier. PERTRONIX is a better product IMO anyways. And it makes me cringe when people start cutting up a factory wiring harness.

With both their module and matching coil, you are going to get a much hotter spark, especially off direct BAT feed.

 

I’m in it this deep already 😊
Why have this high zoot module and fancy coils and not get the full benefits?
It’s another 50 bucks and I’d like it done right.

thanks for all the help and information!

 

Flamethrower 1.5 ohm coils on Amazon $34 free ship.

 

Glad it worked out finally. Had me wondering there for awhile..
Say. I'll send a bill payable only in BUDWEISER HI-TEST ...

 

The power relay will use the ballast output wire to switch the relay. Any idea where the best place to find the ballast or this wire under the hood?
Or, since this relay will send 12V to the coil just like the non ballasted 12V supply from the starter relay why couldn't I just use the current power wire on the coil as the relay control? When the coil is hot the the relay is engaged. Sounds too simple, what am I missing?
Guess I ain't done yet

 

You simply use the present wire to the coil trip the relay.





Do you see how + is connected @ the coil? Two leads, one from relay and second off same post bypasses coil to power module.

 

That’s what I’d hoped for. If the voltage on that wire varies from say 9v to 12v I didn’t know if the relay coil could deal with a range of voltages like that.

 

The OEM wire (off IGN SW) will supply more than needed current to trip the relay. The actual relay is rated @30A, more than adequate for what you need (module and coil draw).

Let the board know how it turns out on this thread if possible..