12v to coil? Elec ign conversion 69
Team Owner
Joined: Jul 2004
Posts: 40,318
Likes: 786
From: Redondo Beach, California
I thing you can get a 12 volt switched ignition source by tapping into the yellow wire that goes to the windshield wiper motor. Maybe someone else can verify this. Anyhow you can easily check by sticking a pin through the yellow plastic insulation and then seeing if the pin is picking up 12 volt switched ignition.
Using the 12 volt source at the fuse box is probably best, since unless careful, splicing into the yellow windshield wire can create a bubba like appearance.
Using the 12 volt source at the fuse box is probably best, since unless careful, splicing into the yellow windshield wire can create a bubba like appearance.
Thread Starter
Racer
Joined: Dec 2009
Posts: 415
Likes: 10
From: Richmond Va
I have the Crane XR-i module and a flamethrower coil. Does the ballast save the coil or the module. The directions talk about a resistor if you have a stock coil or if you run an aftermarket you will need a 1.2-1.9 in line resistor. I have heard a lot of guys run the constant 12v to the coil for hotter spark. I can understand not wanting to overstress a stock unit, but how about an aftermarket coil? Will this be detrimental over time?
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
The stock ballast resistor is for the coil. But, if the Crane unit is not built to take 12v., it may need the ballast resistor too. Crane is shut down due to financial problems at present, but they had a unit that would run with the stock ballast resistor [or wire]. They also made one that operated on 12v. You need to know which one you have. For hotter spark, you would do best to use 12v, but the coil needs to be able to handle the voltage and current absorbed by the spark.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
Suggest read XR-i instructions. They seem clear & concise to me. They were downloadable; dunno about now.
Direct unedited quote verbatim here:
Quick Test for Ballast Resistance
You can determine if your vehicle has external ballast
resistance with this simple test. Disconnect any wires
going to COIL-. Reconnect battery. Turn the ignition
key on but do not start the engine. Use a voltmeter as
shown in Figure 2 and read voltage between COIL+
terminal and ground. It should be about 12 volts. Then
momentarily jumper the COIL- terminal to ground. If
voltage at COIL+ terminal drops below 8 volts, there is
ballast resistance between the ignition key and COIL+
terminal. To determine if your coil has internal ballast
resistance, use an ohm meter as shown in Figure 1.
Coils with internal resistance will read 3 to 4
ohms.from COIL- to COIL+ terminals.
FYI Fig 1 is ohmeter connected at Coil+ & Coil-.
FYI Fig 2 is voltmeter connected at Coil + & Chassis Ground.
Also my OE points coil measures about 2.5 - 3.0 ohms internal; my entire points ignition's connected & wired just as GM intended. Mine retains points 'though I've installed several XR-i in others' cars/trucks.
*everything on the internet's suspect; including the very words I just wrote.
Direct unedited quote verbatim here:
Quick Test for Ballast Resistance
You can determine if your vehicle has external ballast
resistance with this simple test. Disconnect any wires
going to COIL-. Reconnect battery. Turn the ignition
key on but do not start the engine. Use a voltmeter as
shown in Figure 2 and read voltage between COIL+
terminal and ground. It should be about 12 volts. Then
momentarily jumper the COIL- terminal to ground. If
voltage at COIL+ terminal drops below 8 volts, there is
ballast resistance between the ignition key and COIL+
terminal. To determine if your coil has internal ballast
resistance, use an ohm meter as shown in Figure 1.
Coils with internal resistance will read 3 to 4
ohms.from COIL- to COIL+ terminals.
FYI Fig 1 is ohmeter connected at Coil+ & Coil-.
FYI Fig 2 is voltmeter connected at Coil + & Chassis Ground.
Also my OE points coil measures about 2.5 - 3.0 ohms internal; my entire points ignition's connected & wired just as GM intended. Mine retains points 'though I've installed several XR-i in others' cars/trucks.
*everything on the internet's suspect; including the very words I just wrote.
Thread Starter
Racer
Joined: Dec 2009
Posts: 415
Likes: 10
From: Richmond Va
The Flamethrower coil instructions clearly states that if you are running the 1.5 ohm unit w/ an 8 cylinder, to remove the ballast. The Crane elec. unit says to run one.
I hooked up a jumper from the IGN spot on the fuse box to the Coil+ yesterday and it started and ran smoother than it did before. Placebo?
Who knows, but now I will just keep and eye out for any overheating of the coil and how well it starts, runs etc to make sure I have not burnt out any of the components. Guess that is what I get for mixing and matching ignition parts. Should have just got the Ignitor II or III and been done. I do like the rev limiter. Have not tested that yet
I hooked up a jumper from the IGN spot on the fuse box to the Coil+ yesterday and it started and ran smoother than it did before. Placebo?
Who knows, but now I will just keep and eye out for any overheating of the coil and how well it starts, runs etc to make sure I have not burnt out any of the components. Guess that is what I get for mixing and matching ignition parts. Should have just got the Ignitor II or III and been done. I do like the rev limiter. Have not tested that yet
