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Finding 12v in on and run- problem

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Old Aug 8, 2003 | 05:14 PM
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Default Finding 12v in on and run- problem

I am sinishing my 69 GTO project, and am having a hard time finding a good 12v ignition source. I seems like every wirefrom the ignition that is on in start/run drops voltage in start. I had a temporary auxilary ignition switch setup with a 30 amp fuse, witch worked for a while. After running perfect for a half hour or more the wires get real hot blow the fuse. Where can I find a 12v source, or is there a better way.

thanks
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Old Aug 10, 2003 | 01:24 AM
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From: Little Austin
Default Re: Finding 12v in on and run- problem

You should be able to put a lead right off the battery. Run some good 10 gauge wire and fuse it. You should be good to go. When your done all the Pontiac guys can start hating you like they hate me for dropping a "corporate" engine in a Pontiac.

Andrew
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Old Aug 10, 2003 | 07:27 AM
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Default Re: Finding 12v in on and run- problem

A little before my time , but isn't it the ballast resistor that does that ( the little white ceramic thing near the coil). You don't need it any more with the LS1. Like I said I am not really up on old ignition systems, but I thought the ballast resistor cut the voltage on start up. Sorry if I am way off. Just a thought
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Old Aug 11, 2003 | 10:57 AM
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Default Re: Finding 12v in on and run- problem

A little before my time , but isn't it the ballast resistor that does that ( the little white ceramic thing near the coil). You don't need it any more with the LS1. Like I said I am not really up on old ignition systems, but I thought the ballast resistor cut the voltage on start up. Sorry if I am way off. Just a thought
I used to run a ballast resistor with my MSD/Unilite ignition on a 73 Lemans..Never knew what the hell it was for.....but you described it right...

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Old Aug 11, 2003 | 10:58 AM
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Default Re: Finding 12v in on and run- problem

I am sinishing my 69 GTO project, and am having a hard time finding a good 12v ignition source. I seems like every wirefrom the ignition that is on in start/run drops voltage in start. I had a temporary auxilary ignition switch setup with a 30 amp fuse, witch worked for a while. After running perfect for a half hour or more the wires get real hot blow the fuse. Where can I find a 12v source, or is there a better way.

thanks
Fuse box, what are you trying to hook up?
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Old Aug 11, 2003 | 05:00 PM
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Default Re: Finding 12v in on and run- problem

So I have a wire from battery rigged with a switch and fuse. Cranked and fired right up but I am still having a problem with fuse life, 20amp ran about 10 min and blew. I have run out of 30amps for now but will hopefully try it tonight. If 30 amp blows after 20-30 minutes, what is my next option? Any ideas?
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Old Aug 11, 2003 | 11:04 PM
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Default Re: Finding 12v in on and run- problem

So I have a wire from battery rigged with a switch and fuse. Cranked and fired right up but I am still having a problem with fuse life, 20amp ran about 10 min and blew. I have run out of 30amps for now but will hopefully try it tonight. If 30 amp blows after 20-30 minutes, what is my next option? Any ideas?
what are you hooking up? If you are blowing 20-30 amp fuses
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Old Aug 12, 2003 | 12:47 AM
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From: Little Austin
Default Re: Finding 12v in on and run- problem

You should not be pulling that much current with the computer. How is your fuel pump hooked up? How are your fans hooked up? Make sure both the fans and the fuel pump are wired through a relay. If either of those are wired directly to the leads coming from the computer, then that would cause the high draw on your main power feed to the computer.

Andrew
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Old Aug 12, 2003 | 12:53 PM
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Default Re: Finding 12v in on and run- problem

Both the fuel pump and my fans are run through relays, so I don't think that is the problem. But I must have messed up somewhere, finding that will be fun.
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