Moparchat - Home of MOPAR enthusiasts worldwide!



Go Back   Moparchat - Home of MOPAR enthusiasts worldwide! > Technical Forums > Performance Talk

Click here to search for Mopar cars and parts for sale.


Reply
 
Thread Tools Display Modes
  #1  
Old 01-11-2002, 02:05 PM
937CHARGER 937CHARGER is offline
Inactive User
 
Join Date: Feb 2001
Location: Tipp City, OH
Posts: 16
Question GM HEI vs. Mopar ignition modual

Is there any advantage to using a GM HEI modual vs. a Mopar modual ?
Reply With Quote
  #2  
Old 01-11-2002, 03:50 PM
jelsr jelsr is offline
Inactive User
 
Join Date: Dec 2001
Location: Dighton, Kansas
Age: 84
Posts: 1,253
Default

I was a mechanic for the Kansas Dept. of Trans. for 30 yrs. then Equipment Supt. for another 4 yrs. We had just about every make and model of car, pickup, truck, etc. I probably replaced 10-12 HEI modules to 1 Mopar ECU. The Fords were somewhere in between. Reliabilitywise, it's not a contest. Outputwise a tossup.
Reply With Quote
  #3  
Old 01-11-2002, 11:18 PM
djswwg djswwg is offline
Inactive User
 
Join Date: Apr 2000
Location: in my garage
Posts: 1,401
Default

jelsr. Yes, but what was the ratio of Mopar to GM vehicles. The answer makes your answer far more realistic............djs
Reply With Quote
  #4  
Old 01-11-2002, 11:47 PM
goldduster goldduster is offline
Inactive User
 
Join Date: Dec 1999
Location: Corry, PA
Posts: 535
Default

GM Modules are smaller, easier to come by, and the High-Performance Modules are cheaper.

When using an aftermarket coil, the GM Module does not require the use of the ballast resistor, which allows 13.6V to reach the coil instead of 12V. Coil output goes up proportionally. The higher output of the coil allows the plug gap to be opened up quite a bit in some cases, and allows a smoother, lower idle.

There are most likely many more GM cars out there running HEI than Mopar Electronic. As long as you don't run your wires too long, the HEI will last a LONG time.

And the GM HEI unit is not a shock hazard
Reply With Quote
  #5  
Old 01-12-2002, 11:52 AM
jelsr jelsr is offline
Inactive User
 
Join Date: Dec 2001
Location: Dighton, Kansas
Age: 84
Posts: 1,253
Default

djswwg-Actually untill '78 when Mopar stopped building trucks they were the more common of the three, pickups were the same. We kept trucks for 175K, pickups for 140K. In FY79 we went to diesel with IHC/Navistar usually the lowest bidder. GM was usually the lowest bidder for pickups with the 6.2/6.5 engine, a real thrill there!
Back to the ignition, it was unusual to have ignition problems with the "Magic Black Box" in the Mopars. The "double" ballast resistor however was an everyday occurance. All my trucks and pickups (Mopars) carried a spare in the glovebox. Operator were instructed "If you shut it off for a short time and it won't restart, change the resistor before you call for a mechanic."
Reply With Quote
  #6  
Old 01-13-2002, 01:01 AM
djswwg djswwg is offline
Inactive User
 
Join Date: Apr 2000
Location: in my garage
Posts: 1,401
Default

jelsr, thanks for the clarification. As for the GM 6.2 and 6.5, I hear you loud and clear. What gross engines! cheers.......djs
Reply With Quote
  #7  
Old 01-14-2002, 11:14 AM
937CHARGER 937CHARGER is offline
Inactive User
 
Join Date: Feb 2001
Location: Tipp City, OH
Posts: 16
Default

Thanks for the info. souds like I should consider other options. I was looking for a low budget upgrade for the ignition in my daily driver pickup.
Reply With Quote
  #8  
Old 01-14-2002, 02:46 PM
Jims451 Jims451 is offline
Inactive User
 
Join Date: Mar 2001
Location: Littleton, Colorado
Age: 59
Posts: 924
Default

I'm confused by the post?
Do you mean using a GM style HEI distribitor/coil/cap unit vs. the MP Electronics ignition conversion kit? (or Mopar stock electronic, dual ballast resistor, ignition?)

Or do you mean that you want to a GM HEI ignition Module electronics with a Mopar Distribitor in place of the Mopar ECU?

As far as I know the only advantage would be less wiring, and I think the GM HEI would need the aftermarket electronics and coil to work as well as the Mopar setup (assuming the Mopar setup is using a good ignition coil.)
The large HEI cap may cause clearance problems in some cars too.
Reply With Quote
  #9  
Old 01-14-2002, 02:59 PM
937CHARGER 937CHARGER is offline
Inactive User
 
Join Date: Feb 2001
Location: Tipp City, OH
Posts: 16
Default

I mean, only swap the ignition moduals. not distributor or coil.
Like is shown on Golduster's web site.

http://liquid2k.com/duster318/tech/hei.html
Reply With Quote
  #10  
Old 01-14-2002, 04:44 PM
goldduster goldduster is offline
Inactive User
 
Join Date: Dec 1999
Location: Corry, PA
Posts: 535
Default

This is pretty much the system that I am installing (sorry, it would be installed, but my car had other problems that had to be done first):

Distributor: 1978 Mopar 318 Vaccum/Mecanical Advance
Coil: Accel Super Stock Street (the round yellow one)
Ignition Module: 4-pin Stock (for now) from 1976 Caddy Fleetwood with a 425 V8
Ballast Resistor: None, replaced with single 14 guage jumper wire.

I just made the harness as it says on my website to tie the whole thing together. It has been installed on numerous cars with very good results.

I do realize that you have to do some junkyard scrounging and a little bit of electrical work to build this, but it is a much simpler installation than the Mopar Electronic (especially in Pre-70 cars and vehicles equipped with Lean Burn)

The thing that i hear every time about it is that it idles lower and smoother.
Reply With Quote
  #11  
Old 01-14-2002, 05:37 PM
Jims451 Jims451 is offline
Inactive User
 
Join Date: Mar 2001
Location: Littleton, Colorado
Age: 59
Posts: 924
Default

I see
I don't really see much benifit in the conversion, and I would add a heat sink to the GM module too.

I have also read that the stock GM ignition output falls off quickly at higher RPM range, but I don't know if that is due to the electronics module or the ignition coil they use?

With the aftermarket Mopar electronic ignition boxes like the MP orange or Chrome box that only use the single ballast resistor, the single ballast resistor is really there more to keep the coil from overheating than protecting the ECU. I don't know the specifics on the GM HEI, but the coil may have had an internal ballast resistor (or higher resistance windings?)

What I'm tring to say is the ballast resistor may have more to do with the ignition coil being used, not the electronics module.
Reply With Quote
  #12  
Old 01-14-2002, 06:02 PM
goldduster goldduster is offline
Inactive User
 
Join Date: Dec 1999
Location: Corry, PA
Posts: 535
Default

Well, it does mostly have to do with the coil.

Correct me if i'm wrong, but i think that the Mopar Electronic Igniton box also gets its power from the Postive (+) side of the coil, which also means that the voltage is dropped right there (just like with the coil), hense protecting the ECU at the same time.

High-Performance HEI Modules that go to 7,000rpm cost $40.00 and are available from numerous sources.
Reply With Quote
  #13  
Old 01-14-2002, 06:16 PM
Jims451 Jims451 is offline
Inactive User
 
Join Date: Mar 2001
Location: Littleton, Colorado
Age: 59
Posts: 924
Default

The Mopar (orange, chrome) ECU gets full +12v power from the "run" position of the ignition switch. It just tap in right before the ballast resistor. The other side of the ballast resistor goes to the coil and has a wire that leads to the "start" position of the ignition key, by-passing the ballast resistor on start-up.

The Original Mopar ECU that uses the dual ballast has one power +12v sourve and another power source supplied from the high resistance side of the dual ballast resistor.

Like I said, either setup should work about the same.
Reply With Quote
  #14  
Old 01-14-2002, 11:01 PM
5thAve 5thAve is offline
Member
 
Join Date: Aug 1999
Location: Canada
Posts: 406
Default

Both are just as simple to install, having leanburn makes the job a couple minutes longer to add in the ballast, but it's not a major deal. The only reason I'd ever run the Gm setup would be if for some reason the ECU was prone to dieing and I was in an area that it wasn't redily available at.

OR if I was doing the conversion and for some reason could only get the vacuum distributor from a junk yard and not the ECU or ballast.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
BB 440 mopar electronic ignition kit JoeM29 Rear Wheel Drive - Parts for Sale 1 01-10-2005 10:51 AM
Performance Modual Ugg Durango Chat 6 11-04-2003 07:31 AM
Ignition up grade (mopar) ProStreet_Kev Performance Talk 6 07-13-2003 07:11 PM
mopar ignition jleilich Performance Talk 4 11-12-2002 01:39 AM
HEI ignition for mopar smallblocks RALPH Performance Talk 3 08-05-2002 05:47 PM




All times are GMT -4. The time now is 05:46 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
. . . . .