Slant *        6        Forum
Home Home Home
The Place to Go for Slant Six Info!
Click here to help support the Slant Six Forum!
It is currently Thu Mar 28, 2024 11:20 pm

All times are UTC-07:00




Post new topic  Reply to topic  [ 7 posts ] 
Author Message
PostPosted: Wed Apr 23, 2003 4:31 pm 
Offline
Board Sponsor
User avatar

Joined: Thu Oct 24, 2002 3:54 pm
Posts: 191
Location: Atlanta, Ga
Car Model:
Thanks to the ignition diagrams on the site I was able to narrow down the cause of the ignition going sparkless on my '65 Bcuda. It would shut down after a few seconds or minutes. It started about 6 months ago and the time to shutdown kept decreasing to where she wouldn't start at all. I converted to electronic years ago with an Orange box and MP distributor. The diagrams showed me which wires to check and it came down to an out of spec dual ballast resistor with 0.55 ohms (close) and 1.5 ohms (too high) or maybe a bad box. I ordered a new orange box from Summit Racing ($37.99+7.95SH) and bingo that was it. My question is, is the 1.5ohm reading on one side of the resistor too high?

_________________
"Former Owner" of '65 Barracuda, 225, Auto, MP 2bbl intake, MP cam, Dutra Duals. Presently Moparless.


Top
   
 Post subject:
PostPosted: Thu Apr 24, 2003 12:57 am 
Offline
Board Sponsor
User avatar

Joined: Sat Feb 08, 2003 2:37 pm
Posts: 4194
Location: CA
Car Model:
Make sure when you are measuring the resistor that nothing is hooked up to it. And from what I see on the diagram, the dual ballast should be 0.5 and 5 ohms.. so 1.5 would sound too low. I am not infront of my car now but I can measure my resistor when I am.


Top
   
 Post subject:
PostPosted: Thu Apr 24, 2003 5:57 am 
Offline
Board Sponsor
User avatar

Joined: Thu Oct 31, 2002 10:20 am
Posts: 64
Location: Pembroke, MA
Car Model:
If you have an orange box ECU you do not need the dual ballast resistor. The high resistance side of the ballast resistor is not hooked to anything. Only 4 wires connect to the Orange ECU (and all after market replacement ECU's for that matter), power, (2) to the distributor pickup and the negative side of the coil. They left the fifth pin location on the ECU connector so that they would be a drop in replacement for the early factory 5 pin design.

I would not get too hung up on the value of the other side of the ballast resistor. As long as it's within .2 ohms or so it's not going to have an impact. The purpose of the resistor is to limit current flow through the coil at low rpm's so the coil does not over heat. It does this by the fact that the resistance of the ballast resistor will increase as it gets hotter from the addtional current drawn by the coil at low rpm's.

FYI, the orange, chrome and gold mopar ECU's do not do anything to improve the ignition output, they were designed to support the higher rpm range of modified motors. The orange box is rated to 6000 rpm on an 8 cylinder motor. Since a slant 6 only fires the ignition 3/4 as often as an 8, the orange ECU will support 8000 rpm on a slant. The stock ECU is plenty good for any slant operating up to 6000 rpm.

_________________
Image
Dave Clement
68 Barracuda (Hot-Rod \6)
http://mysite.verizon.net/vze4pgxf/


Top
   
 Post subject:
PostPosted: Thu Apr 24, 2003 4:19 pm 
Offline
Board Sponsor
User avatar

Joined: Thu Oct 24, 2002 3:54 pm
Posts: 191
Location: Atlanta, Ga
Car Model:
Thanks for the info. I mis-typed the high side resistance on my first post. It should have read 5.5 ohms and 1.5 ohms. The Chrome box diagram shows the Compensating resistor at 1.2ohms so I'm close with 1.5. If the high side auxiliary isn't used I should be able to just wire it like the Chrome box diagram and use one of my old point system resistors. Am I right in thinking it will not hurt an Orange box? Or is the lower resistance going to pass too much current to it? By the way Chuck's note on the basic electronic diagram (black box) says that it's compensating resistor is only 0.5ohms instead of 5.0.

_________________
"Former Owner" of '65 Barracuda, 225, Auto, MP 2bbl intake, MP cam, Dutra Duals. Presently Moparless.


Top
   
 Post subject:
PostPosted: Sun Apr 27, 2003 12:08 am 
Offline
Site Admin
User avatar

Joined: Sat Oct 12, 2002 12:57 am
Posts: 1359
Location: Grass Valley, Ca.
Car Model: '63 Dodge Dart GT Convertible
I made that note because I couldn't edit the wiring diagram, as it is a graphhic file. Unfortunately I don't know about the orange boxes. I suspect that the wiring instructions would say what the resistance of the resistor should be, but just guessing.

_________________
Chuck Rivers, Webmaster
Image Image Image Image


Top
   
 Post subject:
PostPosted: Sun Apr 27, 2003 4:58 pm 
Offline
Board Sponsor
User avatar

Joined: Thu Oct 31, 2002 10:20 am
Posts: 64
Location: Pembroke, MA
Car Model:
Mopar switched to the single resistor electronic ignition that is shown in the second diagram http://slantsix.org/articles/elect_ign_ ... wiring.htm on this page in the late 70's.

From that point on all years of mopar replacement ecu's didn't use the compensating resistor either (it is a direct drop in replacement for the 5-wire ecu). Maybe some of the very early Mopar Performance ecu's (Orange, Chrome or Gold) used the compensating resistor but anything you may have purchased since 1980 would only have have 4 connections and does not need the dual ballast resistor. Also, anything you may get from the after market does not use the dual ballast.

FYI, The ballast resistor part number P5206436 that is specified for use with the orange ecu is listed as 1 ohm but the two that I have are marked as .25 ohm.

_________________
Image

Dave Clement

68 Barracuda (Hot-Rod \6)

http://mysite.verizon.net/vze4pgxf/


Top
   
 Post subject:
PostPosted: Sun Apr 27, 2003 5:11 pm 
Offline
Board Sponsor
User avatar

Joined: Thu Oct 24, 2002 3:54 pm
Posts: 191
Location: Atlanta, Ga
Car Model:
Thanks for the help. The new box cured my starting problems and the engine makes decent power again :D

_________________
"Former Owner" of '65 Barracuda, 225, Auto, MP 2bbl intake, MP cam, Dutra Duals. Presently Moparless.


Top
   
Display posts from previous:  Sort by  
Post new topic  Reply to topic  [ 7 posts ] 

All times are UTC-07:00


Who is online

Users browsing this forum: No registered users and 16 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Limited