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2.8 Liter Points ?


RonD

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The resistor was to lower running voltage at the coil (and points) so they didn't run as hot

Most car makers had separate START and RUN wires to the Coil
12volt coil is fine at 12v, problem is when alternator is on its running at 13.5-14.5volts so coil runs way hotter than it needs to
The resistor lowers running voltage by 4 volts, so coil runs at 9-10volts which generates about 20,000volts to spark plugs

But when starting battery voltage DROPS to 9-10volts because of starter motors high AMP draw
If you passed that thru the resistor its 5-6volts, so very very weak spark
As said there was an "I" post on the 4 post starter relays, it has the 9-10volts to send to coil when starter is active, then 0v when starter is off, so just the one extra wire to the Coil + terminal

Once electronic ignitions were here to stay, and coils got better, there was no need for the resistor
So START and RUN both power spark system directly
 


19Walt93

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I wouldn't object to using an HEI module with a Duraspark distributor, or an aftermarket module. Actually, other than early 70's Mopar electronic ignition, everything is better than points.
 

85_Ranger4x4

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I looked into doing this to my truck... to the point I actually gutted a old DS model and made an aluminum plate to fit the module out of sight (AKA Stealth HEI). I noticed an error in my DS install, fixed it and haven't had an issue for several years and counting. I really have had no need to continue the HEI project at all.

Of note, the DS is slightly more advanced than the HEI, the start wire does give it full 12v but it also cues the module to retard the timing slightly to make starting easier. That was a big reason (besides icky GM stuff) I was hesitant to go HEI.

The "correct" resister wire was $40, a ceramic ignition resistor was like $5. I think it calls for 1.5 ohm, check for sure though.
 

RonD

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If you use a later model coil(1990 or newer) you don't need the resistor wire at all
Just need a 12volt wire that has 12v in both START and RUN key positions

The "I" post may be the most convenient for START 12v on older vehicles, but certainly not needed if ignition switch has 12v in both positions, which later models do
 

85_Ranger4x4

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If you use a later model coil(1990 or newer) you don't need the resistor wire at all
Just need a 12volt wire that has 12v in both START and RUN key positions

The "I" post may be the most convenient for START 12v on older vehicles, but certainly not needed if ignition switch has 12v in both positions, which later models do
I do know an '85 e coil will melt down modules and coils in short order. I got about 6 months before the module and/or the coil (sometimes both at the same time) would die. I noticed the computer was still getting tach signal so I took all that out and then I could melt down a module at idle in 5 minutes. The resistance of whatever the computer was doing was actually helping. A 95 F-150 calls for the same coil as a '85 Ranger.

I put the "correct" canister coil in and I haven't had a reason to touch it in 2.5 years and counting.
 

RonD

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That is odd
I only have diagrams back to 1986 but no resistor was used, except on tach signal to computer

There were two separate wires from ignition switch for RUN and START, from the old resistor days, but they were spliced together

And I thought Rangers used the same grey TFI module from 1983 and up
 

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85_Ranger4x4

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That is odd
I only have diagrams back to 1986 but no resistor was used, except on tach signal to computer

There were two separate wires from ignition switch for RUN and START, from the old resistor days, but they were spliced together

And I thought Rangers used the same grey TFI module from 1983 and up
This is from the '85 EVTM



'88 EVTM



The 2.8 had TFI but when you convert to duraspark you don't care about that, everything else needs to be like a 2.0 not a 2.8. This is the 2.8.

 
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RonD

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So Duraspark module specific not TFI, got it
 

19Walt93

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I looked into doing this to my truck... to the point I actually gutted a old DS model and made an aluminum plate to fit the module out of sight (AKA Stealth HEI). I noticed an error in my DS install, fixed it and haven't had an issue for several years and counting. I really have had no need to continue the HEI project at all.

Of note, the DS is slightly more advanced than the HEI, the start wire does give it full 12v but it also cues the module to retard the timing slightly to make starting easier. That was a big reason (besides icky GM stuff) I was hesitant to go HEI.

The "correct" resister wire was $40, a ceramic ignition resistor was like $5. I think it calls for 1.5 ohm, check for sure though.
Napa used to sell a pink resistor wire about 6 feet long for just a couple of bucks.
 

ford4wd08

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I believe y'all are talking duraspark modules, but I'm using the square TFI coil on my '85 with the GM HEI with zero issues so far.

All I had to do was run + and - from coil and hook up distributor. The rest of the wiring is stock from the '85 B2.
 

franklin2

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I believe y'all are talking duraspark modules, but I'm using the square TFI coil on my '85 with the GM HEI with zero issues so far.

All I had to do was run + and - from coil and hook up distributor. The rest of the wiring is stock from the '85 B2.
The HEI module will take the 12v power without using a resistor. It has current limiting circuits inside it to let it be hooked up this way. The duraspark II module requires the resistor to limit the current through the coil, which then limits the current through the module. Like someone mentioned in a earlier post, a duraspark II system without a resistor will make the module run hot and not last very long.

Some people use the square coil with the duraspark II module and don't have any problems. I am hesitant on this also, the square coil draws more power, and this power has to run through the module. I also don't like running "hot" aftermarket coils with the duraspark module. These other coils may work fine, but I like running the original horseshoe connector duraspark coil.
 

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as for a point set up, this is what I used on my 1985, once running okay, I converted to duraspark, but, can switch back to points in an hour or so.

1974 pinto carb (elec and heat choke)
1974 pinto dist - mech and vac advance

ignition coil
Accel 8140

Ign. Resistor:
BWD RU19

Spark Plugs:
Autolite 765
gapped .035

fuel filter:
Mr. Gasket #9748 clear glass

air filter
10x2 Edelbrock
(too small)
 

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