Page 2 of 2 < 1 2
Topic Options
#2414666 - 12/07/17 10:29 AM Re: Accel Yellow SuperCoil input voltage [Re: RapidRobert]
moparx Offline
Dreaming of implants

Registered: 09/03/03
Posts: 8722
Loc: north of coder
the older i get, i find out the dumber i really am, and my old man was a lot smarter than i gave him credit for.
beer

Top
#2414668 - 12/07/17 10:30 AM Re: Accel Yellow SuperCoil input voltage [Re: Diplomat360]
540DUSTER Offline
mopar

Registered: 12/27/03
Posts: 519
Loc: USA
I always thought the resistor was to keep the points from arching.

Top
#2414674 - 12/07/17 10:40 AM Re: Accel Yellow SuperCoil input voltage [Re: 540DUSTER]
Supercuda Online   content
I Live Here

Registered: 09/04/07
Posts: 13063
Originally Posted By 540DUSTER
I always thought the resistor was to keep the points from arching.


That is the capacitor (condenser) inside the distributor's job.

That's why you should replace the condenser and the points together.

Top
#2414897 - 12/07/17 05:25 PM Re: Accel Yellow SuperCoil input voltage [Re: Diplomat360]
383man Offline
Too Many Posts

Registered: 01/19/03
Posts: 26679
Loc: Balt. Md
One thing I might add is that GM and Ford also used a resistance in their coil primary circuits with points as they both used a resistance wire in the wire harness but I have read that they were not temp sensitive as the Mopar ballast is. So from what I read about the GM and Ford resistance wire is they dont change resistance by temp change from current flow. Ron
_________________________
My car...63 Sport Fury Max Wedge wanna be street car..with new 493 pump gas full exh eng.......10.76 @ 124.49 ! ! ! My page on the cool 62-65 Mopar site ! http://www.1962to1965mopar.ornocar.com/mmo82008.html

Top
#2414923 - 12/07/17 06:15 PM Re: Accel Yellow SuperCoil input voltage [Re: Saskabusa]
Dcuda69 Offline
master

Registered: 10/17/05
Posts: 3931
Loc: WI
Originally Posted By Saskabusa
Originally Posted By Supercuda

As for the effects on what ever, there should be NO changes, that is the purpose of the ballast to maintain a constant primary current with variation in engine speed. That means a stable ignition with no variations related to engine speed.




The ECU is a transistor that grounds the coil to give you the high voltage spark. The primary current has to go to ground through it. It will have some limit to how much current it can safely handle but I don't know what that is.


This would be my concern.Is the ECU up to the task of carrying the current flow through the primary with a full 12-14 volts on the positive side.Current flow through that transistor will be noticeably higher at 12-14 volts than at 9 volts. The coil will likely be fine....will the ECU? Time will tell.

Top
#2414930 - 12/07/17 06:33 PM Re: Accel Yellow SuperCoil input voltage [Re: Diplomat360]
Supercuda Online   content
I Live Here

Registered: 09/04/07
Posts: 13063
All in what transistor you specify.

they make power transistors capable of handling the current flow.

Top
#2414932 - 12/07/17 06:36 PM Re: Accel Yellow SuperCoil input voltage [Re: Diplomat360]
Mattax Offline
super stock

Registered: 02/28/10
Posts: 1105
Loc: Phila. Pa.
Lots of good discussion here.

As far as the manufacturer recommended matches, let me add this from Direct Connection.

With the Accel 150001 Coil, there is only combination listed.
ECU: Chrome (p4120889, P4007298, p4120505, p4120534)
Resistance value: 0.8 Ohms
All applications to 6000 rpm

From this, assuming your Chrome box is one of these or similar, I'd say .75 is a good match thumbs

This is taken from Figure 19-6 page 368 of Mopar Engine, Speed Secrets edition. This version is terribly edited but I think my interpretation of the chart is correct. It may have been printed earlier as a Direct Connection "Chrysler Ignition Systems" bulletin.

Interesting. None of the combinations recommended in that table use a higher resistance. work

Top
#2414955 - 12/07/17 07:32 PM Re: Accel Yellow SuperCoil input voltage [Re: Supercuda]
Dcuda69 Offline
master

Registered: 10/17/05
Posts: 3931
Loc: WI
Originally Posted By Supercuda
All in what transistor you specify.

they make power transistors capable of handling the current flow.


Of course "they" make capable transistors.Modern ECMs are full of them.What we don't know is if "they" specified a capable one in the ECU being used. As I said...time will tell.

Top
#2414962 - 12/07/17 07:44 PM Re: Accel Yellow SuperCoil input voltage [Re: Diplomat360]
Supercuda Online   content
I Live Here

Registered: 09/04/07
Posts: 13063
All you have to do is look up the specifications, they are not secret. If you have the maker and the number, should be stamped on the housing.

Top
#2414976 - 12/07/17 08:14 PM Re: Accel Yellow SuperCoil input voltage [Re: Supercuda]
Dcuda69 Offline
master

Registered: 10/17/05
Posts: 3931
Loc: WI
Originally Posted By Supercuda
All you have to do is look up the specifications, they are not secret. If you have the maker and the number, should be stamped on the housing.


Knock yourself out. Not my ECU. I simply agreed with the other member that I would be more concerned about the ECU(transistor) than I would be about the coil.

Top
#2414981 - 12/07/17 08:19 PM Re: Accel Yellow SuperCoil input voltage [Re: Supercuda]
Saskabusa Offline
enthusiast

Registered: 12/20/05
Posts: 253
Loc: Scatchamatoon
Originally Posted By Supercuda
All in what transistor you specify.

they make power transistors capable of handling the current flow.


I am referring to the transistor in the stock mopar ECU.

It is the "switch" that cycles the current to the coil. It is triggered by the pickup in the distributor.


Originally Posted By Dcuda69
Originally Posted By Saskabusa
Originally Posted By Supercuda

As for the effects on what ever, there should be NO changes, that is the purpose of the ballast to maintain a constant primary current with variation in engine speed. That means a stable ignition with no variations related to engine speed.



The ECU is a transistor that grounds the coil to give you the high voltage spark. The primary current has to go to ground through it. It will have some limit to how much current it can safely handle but I don't know what that is.


This would be my concern.Is the ECU up to the task of carrying the current flow through the primary with a full 12-14 volts on the positive side.Current flow through that transistor will be noticeably higher at 12-14 volts than at 9 volts. The coil will likely be fine....will the ECU? Time will tell.


Yea there is no way to really know. Thats why I would just follow the directions from Accel.


Edited by Saskabusa (12/07/17 08:22 PM)
_________________________
1974 Roadrunner

1967 Charger

Top
#2415007 - 12/07/17 09:09 PM Re: Accel Yellow SuperCoil input voltage [Re: Saskabusa]
Supercuda Online   content
I Live Here

Registered: 09/04/07
Posts: 13063
Originally Posted By Saskabusa
Originally Posted By Supercuda
All in what transistor you specify.

they make power transistors capable of handling the current flow.


I am referring to the transistor in the stock mopar ECU.

It is the "switch" that cycles the current to the coil. It is triggered by the pickup in the distributor.


I know exactly how it works and if you want nauseating detail of a technical nature that can be supplied, for a price.

And as I said, the specs for even the OEM ECU's power transistor are available, it is no secret. It's a Motorola MJ10012

Spec sheet

Some have used a Motorola MJ10005 as a more available replacement.

Spec Sheet

Top
#2415029 - 12/07/17 09:50 PM Re: Accel Yellow SuperCoil input voltage [Re: Diplomat360]
Dcuda69 Offline
master

Registered: 10/17/05
Posts: 3931
Loc: WI
Great info. So at .7 ohms of primary resistance in the coil and 13 volts at the coil positive one of those will be questionable and one will be fine? How do ya know which is in his ECU? Back to....time will tell?

http://www.jegs.com/i/Accel/110/140001/10002/-1

Top
Page 2 of 2 < 1 2

Advertisement
Sponsored Link
Forum Stats
25,343 Registered Members
32 Forums
190,186 Topics
2,218,846 Posts

Most users ever online: 1,417 @ 06/18/18 08:39 PM
Moparts Newest Topics
How do I test a ballast resistor?
by rickseeman
24 minutes 27 seconds ago
Mopars at the Park Fox Lake, ILLINOIS this Sunday!
by Rhinodart
50 minutes 52 seconds ago
monkeys toy
by azmopar
52 minutes 40 seconds ago
How to identify this old Hemi!
by RUMBLON
Today at 11:18 AM