Go Back   The Ford Barn > General Discussion > Early V8 (1932-53)

Sponsored Links (Register now to hide all advertisements)

Reply
 
Thread Tools Display Modes
Old 10-06-2019, 08:56 PM   #1
LQQKER
Member
 
Join Date: Feb 2011
Location: Sarasota Fl area
Posts: 71
Default 12V vs 6V crab distributor

Did a quick Thread search but no luck.


Acquired a good running crab distributor off a 6 volt car. What changes if any are required to this distributor to run on an engine converted to 12V ?

Condenser maybe? Using as a spare. Thanks
LQQKER is offline   Reply With Quote
Old 10-06-2019, 09:12 PM   #2
cadillac512
Member
 
Join Date: Apr 2019
Location: Kansas
Posts: 39
Default Re: 12V vs 6V crab distributor

Condenser should be the same. No other changes needed as long as the system is already set up for 12v with proper coil and ballast resistor.



Terry
__________________
"It don't take but country smarts to solve the problem" (Smokey Yunick)
cadillac512 is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 10-06-2019, 09:23 PM   #3
BUBBAS IGNITION
Senior Member
 
BUBBAS IGNITION's Avatar
 
Join Date: May 2010
Location: SPEEDWAY INDIANA
Posts: 3,829
Default Re: 12V vs 6V crab distributor

Yep just change the coil and resistor under dash .
__________________
If it Makes Spark, we do it !!!!
www.bubbasignition.com
jimlinder@juno.com
BUBBAS IGNITION is offline   Reply With Quote
Old 10-06-2019, 09:36 PM   #4
Andy
Senior Member
 
Join Date: May 2010
Location: Kerrville, Tx
Posts: 2,322
Default Re: 12V vs 6V crab distributor

I used the “6V” coil. All coils run on about the same energy. Read the amps with the 6v system. Use a resister that gives half the amperage of the 6V system. That’s what I did.
This may be wrong but worked for me.
Andy is offline   Reply With Quote
Old 10-06-2019, 09:47 PM   #5
tubman
Senior Member
 
tubman's Avatar
 
Join Date: Dec 2013
Location: Minnesota, Florida Keys
Posts: 5,105
Default Re: 12V vs 6V crab distributor

Condenser, points, resistors, contacts, and wires in general are not voltage sensitive.
tubman is offline   Reply With Quote
Old 10-07-2019, 08:20 AM   #6
LQQKER
Member
 
Join Date: Feb 2011
Location: Sarasota Fl area
Posts: 71
Default Re: 12V vs 6V crab distributor

I'm good to go.
Thank you all.
LQQKER is offline   Reply With Quote
Old 10-07-2019, 08:10 PM   #7
philipswanson
Senior Member
 
Join Date: Oct 2015
Location: Bonita, CA
Posts: 932
Default Re: 12V vs 6V crab distributor

Quote:
Originally Posted by tubman View Post
Condenser, points, resistors, contacts, and wires in general are not voltage sensitive.
Resistors may very well be different in a 12v system. That's why Bubba says to change it. Ohm's law dictates. The 12 volt coil determines the resistor needed if any.
philipswanson is offline   Reply With Quote
Old 10-07-2019, 09:33 PM   #8
LQQKER
Member
 
Join Date: Feb 2011
Location: Sarasota Fl area
Posts: 71
Default Re: 12V vs 6V crab distributor

No resistor under the dash. Echlin 12V coil with internal resistor.

I didn't think any mods were required for the 6V unit but I was hoping for reassuring advise from the experts on this forum. This is a spare for a running 12v car. Again....Thanks.
LQQKER is offline   Reply With Quote
Old 10-08-2019, 07:58 AM   #9
tubman
Senior Member
 
tubman's Avatar
 
Join Date: Dec 2013
Location: Minnesota, Florida Keys
Posts: 5,105
Default Re: 12V vs 6V crab distributor

Quote:
Originally Posted by philipswanson View Post
Resistors may very well be different in a 12v system. That's why Bubba says to change it. Ohm's law dictates. The 12 volt coil determines the resistor needed if any.
Wrong again, Phillip. Different voltages may require different resistance, but 10 ohms is 10 ohms. If you look at traditional resistors, they have different colored stripes on them that indicate the stated resistance of the unit. I have never seen a resistor marked with the voltage. You are confusing the resistance required by different circumstances with the value of the resistor itself.
tubman is offline   Reply With Quote
Old 10-08-2019, 02:34 PM   #10
philipswanson
Senior Member
 
Join Date: Oct 2015
Location: Bonita, CA
Posts: 932
Default Re: 12V vs 6V crab distributor

I wasn't wrong. A 12 volt system and coil most likely will require a different resistor or none at all. Of course a given resistor will have the same resistance whether in a 6v system or 12v. The requirement for a DIFFERENT resistor with a different coil will dictate the required ohms. Never said otherwise. Common sense which some lack.

Last edited by philipswanson; 10-26-2019 at 07:12 PM.
philipswanson is offline   Reply With Quote
Old 10-22-2019, 06:57 PM   #11
edhd58
Senior Member
 
edhd58's Avatar
 
Join Date: Jul 2014
Location: Guston,ky
Posts: 616
Default Re: 12V vs 6V crab distributor

Quote:
Originally Posted by BUBBAS IGNITION View Post
Yep just change the coil and resistor under dash .
why does the resistor need changing, asking cause i went 12 v and didnt change anything but the coil on my G
edhd58 is offline   Reply With Quote
Old 10-22-2019, 08:36 PM   #12
JSeery
Senior Member
 
JSeery's Avatar
 
Join Date: Nov 2012
Location: Wichita KS
Posts: 13,194
Default Re: 12V vs 6V crab distributor

Quote:
Originally Posted by edhd58 View Post
why does the resistor need changing, asking cause i went 12 v and didnt change anything but the coil on my G
Depends on what you were starting with and what coil was used. You want something in the 3 ohms range between the coil and any resistance. So if you add an ~1.5 ohm coil it needs ~1.5 ohms of resistance added (a ballast resistor). If an ~3.0 ohm coil is used, a ballast resistor is not required. So, you need to know what the resistance is of the coil you are using and what ballast resistance was originally in the vehicle.
JSeery is offline   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

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 07:47 PM.