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Resistor or Not with MSD coil wd45

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Topic: Resistor or Not with MSD coil wd45
Posted By: TennMatt1
Subject: Resistor or Not with MSD coil wd45
Date Posted: 21 Oct 2015 at 2:01pm
I have pertronix igniter module in my wd45 and it has the stock coil. I just went and bought a msd blaster 2 coil for it but the old one has a resistor on the outside of it. Do I need to keep that or not? Tractor is already 12v negative ground. Thanks for the help in advance.



Replies:
Posted By: Steve in NJ
Date Posted: 23 Oct 2015 at 7:10am
If you still have the 45' engine in it, you need 2.7-3.3 Ohms of resistance in the Ignition circuit. Make sure that Blaster coil is within that spec. 3.0 Ohm is ideal. I would make a phone call to Pertronix and ask them. They'll tell ya what you need and what will work. Its very easy to burn up a module...
Steve@B&B

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39'RC, 43'WC, 48'B, 49'G, 50'WF, 65 Big 10, 67'B-110, 75'716H, 2-620's, & a Motorhead wife


Posted By: TennMatt1
Date Posted: 29 Oct 2015 at 11:45pm
Please elaborate on that please. Why does it matter on the ohms? I understand most of it but I would think since it was converted to 12v and has a alternator that I wouldnt need a resistor.Doesnt it cut back my voltage ?? And if so wouldnt it fire better at 12v??



Posted By: CAL(KS)
Date Posted: 30 Oct 2015 at 7:54am
ohms of resistance in the ignition coil. without going into electrical theory, 8 cylinder engines require different ohms than 4-6 cylinder engines or the pertronix module could be damaged. you can check the pertronix instructions online

http://pertronix.com/support/instructions/" rel="nofollow - here

also coils are classified for inductive discharge or capacitive discharge ignition systems

straight from pertronix....

1. The Ignitor is designed for 12-Volt negative ground systems.
2. Leaving the ignition “ON” with the engine “OFF” for an extended period could result in permanent damage to
the Ignitor.
3. See Chart on back page for coil recommendations.
4. Four & Six cylinder engines require a minimum of 3.0 ohms of primary resistance. Do not remove resistors if
the coil primary resistance is less than 3.0 ohms.
5. If your Ignition coil has the recommended primary resistance, remove or bypass all external resistors.
6. The Ignitor is compatible as a trigger for most electronic boxes.

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Me -C,U,UC,WC,WD45,190XT,TL-12,145T,HD6G,HD16,HD20

Dad- WD, D17D, D19D, RT100A, 7020, 7080,7580, 2-8550's, 2-S77, HD15


Posted By: Dnoym N. S. Can.
Date Posted: 30 Oct 2015 at 8:11am
I don`t understand why people want a bigger
coil they don`t give more spark unless there
a problem  a coil only put out the amount of
spark that it take to over come the resists of
the system   it capable of giving more but it
just stay in the coil and don`t do noting
IMHO
    B:-)      Dnoym   


Posted By: bigcountry48
Date Posted: 30 Oct 2015 at 4:20pm
Msd coil puts out multiple Sparks, it helps to fully burn all the gas in the cylinder thus making it run better. It doesn't just make a higher voltage spark.

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1950 B, 1952 pulling wd, and 1954 wd45


Posted By: Dnoym N. S. Can.
Date Posted: 30 Oct 2015 at 6:01pm
thanks   bigcountry48  

so that would mean that multiple sparks
 improved idle stability and low speed
operation with engines having radical
aftermarket cams or even  with stock
cams. Multiple sparks can lessen
problems with misfire at idle.
but i don`t think that the

msd blaster 2 coil is a
Multiple sparks coil ??

   B:-)        Dnoym


Posted By: bigcountry48
Date Posted: 30 Oct 2015 at 8:14pm
sorry, didn't mean to disagree with you. But like they say at every tractor pull drivers meeting I've ever been to, we all came as friends so let's make sure we all leave as friends! Just make sure that old nasty beat up coil isn't on there when it's done, they don't look to good on those nice pretty pulling tractors!

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1950 B, 1952 pulling wd, and 1954 wd45


Posted By: Mrgoodwrench
Date Posted: 30 Oct 2015 at 10:03pm
A msd coil alone will not put out multiple sparks, that would take a msd "box". Their coils are just high voltage coils. I'm not knowledgeable enough to say whether or not the extra voltage is useful.

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There are 3 ways to do job GOOD, FAST, CHEAP. YOU MAY CHOOSE 2. If its FAST & CHEAP it won't be GOOD, if it's GOOD & CHEAP it won't be FAST, and if its GOOD & FAST it won't be CHEAP!!!!


Posted By: bigcountry48
Date Posted: 30 Oct 2015 at 10:10pm
The petronix system creates the multi spark, the coil just works with it.
http://pertronix.com/prod/ig/ignitor/

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1950 B, 1952 pulling wd, and 1954 wd45


Posted By: CAL(KS)
Date Posted: 31 Oct 2015 at 5:05am
only the ignitor 3 is multiple spark capable. a regular pertronix ignitor is just a magnetic switch  that will not wear like points, but does have other benefits.  it is trigger capable for a capacative discharge ignition that can create multiple sparks like a MSD box.

MS ignitions are usually not allowed in near stock pulling like NATPA div 1,2


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Me -C,U,UC,WC,WD45,190XT,TL-12,145T,HD6G,HD16,HD20

Dad- WD, D17D, D19D, RT100A, 7020, 7080,7580, 2-8550's, 2-S77, HD15


Posted By: bigcountry48
Date Posted: 31 Oct 2015 at 6:27am
Oh ok, petronix website says all the petronix systems have multi spark triggers. I must have read that wrong.
http://pertronix.com/prod/ig/ignitor/

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1950 B, 1952 pulling wd, and 1954 wd45


Posted By: TennMatt1
Date Posted: 02 Nov 2015 at 7:44pm
As I was re-routing wires I turned my coil and its actually a flamethower fom pertronix. It's a 1.5 ohm coil so that would explain the resistor.




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