Adjusting Six Pack carbs...Timing, transfer slot size, idle screw adjustment

[734406PK]

Thanks for the replies

I didn't get much time to tinker with it over the weekend but I'm starting to think I might have underlying ignition issues.
It seemed the more I messed with tuning the carbs the worse it ran.

I'm using the idle mixture screws and special tool from SixPack Solutions so I'm able to adjust the rear carb's mixture screws without removing it. It never had plugs in the front carbs because they are repops?
I started with the mixture screws on the outboards at 1/8th turn open then moved them to 1/4 turn but again I think there are other issues I need to check before trying the adjust carbs any more.

I think the engine might be suffering from a weak spark.
The engine just sounds and feels weak like it' not running on all cylinders all the time.
It will idle OK but stalls when put in gear.
I pulled a couple plugs and they looked very dark and sooty?
The engine seemed to run much better when I first got it started but something seems to be deteriorating.

The engine wiring harness is new from Year One.
I'm using a new Hi_Rev brand factory type ECU and a dual field (4 pole) ballast resistor (which I had to use because the YO wiring harness was wired for it) and a MSD blaster 2 coil which was used but looked like new.
Will a factory type dual ballast resistor have isses with the Blaster 2 coil because of the OHM rating difference?
Firecore distributor and wires, most all wiring is new.

When tuning under the hood I normally use a push button remote starter wired into the starter relay to start the engine.
Towards the end I noticed the car would turn over but would not start using the push button on the starter relay, I had to go inside and start the engine using the key which the engine did start and run.
I don't have much wiring troubleshooting experience but could this be caused by a failing ballist resistor giving too low of volts on the lower run side?
Bad coil or ECU?
One recent event that might be important is when I took the car to have the exhaust installed a couple weeks ago I believe the ignition key was left in the run position(engine off) the entire time the exhaust was installed so something in the ignition system might have been hurt?
The car started right up and drove home OK that day but the engine just doesn't feel right...
I have available another dual ballast resistor off a currently running car along with a different coil and ECU I was thinking of swapping out to test.

For those who are good at electircal troubleshooting what suggestions do you have?
I've done some research on checking the OHM's on the ballast and OHM's and volts at the coil but I really am a rookie at electrical stuff.

Thanks for any suggestions or advice.

I'll do some research on your ignition set up, but you are on the right track! Carb adjustment is the last step in the tuning process, everything else must function 100% first. I agree, i think you have another problem that needs to be corrected first before carb adjustment. Good info on the ignition issue! I'm not sure if the ignition components you have are all compatible, but will check. The best way to test a coil w/o expensive equipment is to replace it with a known good coil. What you don't want to do here is make unnecessary and irreversible mods to your carbs to compensate for an engine problem.

[734406PK]

This info popped up on the JEGS Site:

Coils made for C-D ignitions (MSD, etc) may destroy the Ignition Control Unit. Coil Primary resistance should be no lower than 1.4Ω

http://www.jegs.com/i/JEGS-Performance-Products/555/40805/10002/-1?CAWELAID=1710882104&CAGPSPN=pla&CAAGID=39714413703&CATCI=pla-293995373017&CATARGETID=230006180039220954&cadevice=c&gclid=CjwKCAjw0qLOBRBUEiwAMG5xMHnJ2ThaKr28LKSBDesHEoY3cjZOWt9EVlSIs32oyP9OS8hOq_B4HxoC3QUQAvD_BwE

And this from Mancini Racing:
http://www.manciniracing.com/msdblascoilr.html

[GrandpaKevin]

Thanks for the info.

Unfortunately the other coil I have is also a older MSD Blaster 2, it has always worked well on the other car with an older chrome box ECU but I think I'm going to get a new, more stock type coil at the parts store.
https://shop.advanceautoparts.com/p/driveworks-ignition-coil-26189/10703783-P?searchTerm=+coil

[734406PK]

Thanks for the info.

Unfortunately the other coil I have is also a older MSD Blaster 2, it has always worked well on the other car with an older chrome box ECU but I think I'm going to get a new, more stock type coil at the parts store.
https://shop.advanceautoparts.com/p/driveworks-ignition-coil-26189/10703783-P?searchTerm=+coil

Check the resistance on the primary side of the replacement coil. Hirev wants 1.4 ohms or higher to limit current flow.

[GrandpaKevin]

Thanks for the info.

Unfortunately the other coil I have is also a older MSD Blaster 2, it has always worked well on the other car with an older chrome box ECU but I think I'm going to get a new, more stock type coil at the parts store.
https://shop.advanceautoparts.com/p/driveworks-ignition-coil-26189/10703783-P?searchTerm=+coil

Check the resistance on the primary side of the replacement coil. Hirev wants 1.4 ohms or higher to limit current flow.

Well that's where my electrical inexperience comes in.
I think the paperwork that came with the HiRev describes how to test that with an OHM meter?

[734406PK]

No Problem! Connect an ohm meter between the positive coil terminal and the negative terminal (where the ICU connects). Read the ohms value. It must be 1.4 ohms or more Use an accurate digital ohm meter so you don't have to worry about reading the right scale on an old analog meter (needle style).

Here is a coil from Pertronix that meets the spec:
http://www.jegs.com/i/Pertronix/751/40011/10002/-1

OR better yet, an epoxy filled version:
http://www.jegs.com/i/Pertronix/751/40111/10002/-1

[HP_Cuda]

A coil check might be worthwhile before tearing down six pack carbs.

A post I made previously on another site which seems relevant:

I have done some more digging and it seems if you go with an ECU setup you will need to protect both the coil and the ECU. Hence the ballast resistor comes to the rescue.

I have the MSD Blaster 2 coil which has a .700 ohms resistance in it already. This is why MSD will sell you a .800 ohm resistor for a total of 1.5ohms which would put you at 8 amps for a V8 (acceptable - read below). So (for example) if you have a stock 1.2ohm resistor with a MSD Blaster 2 coil then you are at a total resistance of 1.9ohms which would affect spark. You could swap out the ballast resistor for one that is .8ohms and should have better performance and longevity.

Ymmv,
B


This is a good read for those wanting to know:
What type of coil can I use with the Ignitor�? How do I check my coils resistance? (12V negative ground only)
To determine if your systems coil is compatible with the Ignitor, some measurements should be taken prior to installation of the Ignitor. Caution� While performing this test, never leave the ignition switch on for more than 30 seconds at a time.

Set your voltmeter to a 15 or 20-volt scale. Attach an 18 or 20 AWG jumper wire from the negative coil terminal to an engine ground. Attach positive (red) lead of your voltmeter to the positive side of the coil, and the negative (black) lead to an engine ground. Turn the ignition switch to the run position. Now read the voltage at the positive coil terminal. Turn the ignition switch off. If the voltage measured is approximately 12 volts, no resistance wire is present. A typical resistance wire will provide 9 - 6 volts.

The next step is to determine the resistance in the primary ignition. Label the wires attached to the coil terminals and note their appropriate location. Make sure that the ignition switch is off and disconnect all wires from the coil. Adjust your meter to the lowest ohm scale. If you are using an analog style meter make sure to zero the needle.

Measure from the negative terminal to the positive terminal. Write your measurement down.

Now the maximum system amperage can be determined, divide your voltage measurement by your coil resistance measurement. This will give you the system current or amperage.

Four and six cylinder engines should not exceed 4 amps. Eight cylinder engines should not exceed 8 amps. If the total amperage in your system is higher than the amount recommended for your application, you should install a ballast resistor.

Example
Voltage 12
Resistance 1.5
12 / 1.5 = 8
Total amperage 8

[GrandpaKevin]

Thanks for the replies, I'm still trying to comprehend all this electrical stuff but the info is very helpful.

If I understand right my current MSD Blaster 2 coil has a built in resistance of .700ohms (do all Blaster 2 coils have this?).
I haven't checked yet but my current stock type 4 prong dual ballast resistor should be around 1.2ohm during the run mode.
So combined with the Blaster 2 coil the total resistance is around 1.9ohms?
Would that make a noticable difference in the way the engine runs and idles?

I do have the .800 resistor that came with the Blaster coil but it is a 2 terminal and I really don't want to start cutting the wiring on the new YO engine wiring harness unless I have to. I've also heard from multiple people the quality/dependabilty of the Blaster 2 coils isn't the best so maybe a different brand coil is the better way to go.

As far as buying a new coil the 2 linked Pertronix coils with a 1.5ohm rating is correct for my current dual ballast resistor's 1.2ohm rating?
I'm currently mounting the coil horizontally in the correct Six Pack coil bracket on the intake, I've done this on other cars with no coil issues, is the epxoy filled coil a better choice or is it overkill?

Thanks again and keep the comments coming.

[HP_Cuda]

Remember higher resistance means you will have less - 12/1.9 = 6.31

On a side note the MSD blaster coils are meant to be mounted vertically so at first they will work fine but will fail over time. You may want to get a coil you can mount horizontally if that's what you want.

[Roadman]

    The MSD Hi vibration coil can be used horizontally .  https://www.summitracing.com/parts/msd-8222/overview/

[GrandpaKevin]

OK this is where I am confused.

What am I missing.

The above linked Pertronix Flame Thrower coil is listed at 1.5 ohm Primary Resistance?
Am I understanding right that this is even a higher resistance than the current Blaster 2 coil at .700ohms or is the .700ohm resistance something else?

So the 1.5 Flame Thrower coil with my current 1.2 dual field ballast would put the total resistance at 2.7 total resistance?
12/2.7=4.4?

Thanks.

[HP_Cuda]

With the pertronix you could basically eliminate your ballast resistor.

I don't think you want to do that so settling on a coil which has lower resistance and can be mounted horizontally could be your ticket:
https://www.rockauto.com/en/catalog/plymouth,1970,cuda,7.2l+440cid+v8,1231759,ignition,ignition+coil,7060

[GrandpaKevin]

Running without a ballast seems to be a hotly debated topic.

So what coils are people using with the dual field ballast resistors?

[734406PK]

Check the installation notes on the Hi-Rev brand ignition module. It states not to use a coil with less than 1.4 ohms primary resistance and they recommend a 1.0 ohm ballast for street use as well. Its unclear if you add the coil resistance and the ballast, or if their module will handle 8 amps. You may want to call the supplier for more info.

http://www.jegs.com/i/JEGS-Performance-Products/555/40805/10002/-1?CAWELAID=1710882104&CAGPSPN=pla&CAAGID=39714413703&CATCI=pla-293995373017&CATARGETID=230006180039220954&cadevice=c&gclid=CjwKCAjw0qLOBRBUEiwAMG5xMHnJ2ThaKr28LKSBDesHEoY3cjZOWt9EVlSIs32oyP9OS8hOq_B4HxoC3QUQAvD_BwE

[GrandpaKevin]

Thanks for the link.

This is getting more difficult.

One of the items I want to check is the HiRev ECU, as I mentioned earlier the ignition switch was accidentally left in the run position for a few hours while the car was at the exhaust shop.

I'm not sure if the ECU, coil and/or distributor was damaged, the car did start and drive home.

I have an orange ECU and a Mopar electronic distributor that was running good on the car previously that I might swap in.

I wish I had more free time to tinker with the car but right now it's not happening.