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Old 01-20-2014, 02:49 PM
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TWaldo
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I have a couple of questions for a 350/4sp/w-A/C...1st - do I have a "ballast resistor" If so, where is it located in engine compartment? Color of wires? 2nd - I found an unattached connector w/ 1 brown & 1 blue wire near windshield wiper motor on firewall... in a "semi-fried" condition. Insulation is cracking and can tell it got hot at one time. Not sure what it is, since everything seems to be working on car. Anyone have answers?? Thanks...Tom
Old 01-20-2014, 03:17 PM
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hugie82
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Ballistic resistor is usually 2 inches long and white with 1 wire in and 1 wire out. Sometimes they're located on the manifold with a bolt holding it down and sometimes they're on the fire wall. I'm not sure if 71 corvette has one...
Old 01-20-2014, 03:35 PM
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zwede
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'71 used a resistance wire. It goes from the fuse block (engine side) to the coil. If memory serves it had a fabric/textile sleeve over it. It's been years since I removed it.
Old 01-20-2014, 04:08 PM
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Roco71
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Originally Posted by zwede
'71 used a resistance wire. It goes from the fuse block (engine side) to the coil. If memory serves it had a fabric/textile sleeve over it. It's been years since I removed it.
On my 71 the wire appears to be off white in color it may have been yellow at one time with what I thought was a heat resistant fabric covering.
Old 01-20-2014, 04:47 PM
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mamamia69
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The blue / tan wire is for the origninal step-up idol solenoid.
Old 01-20-2014, 05:48 PM
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TWaldo
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Thanks for your replies...car has HEI (going to remove) which could account for ballast resistor being removed? I just got Qjet and original distributor back from Lars. So if it is not there...need it for dist installation...? Correct ?

As for blue/tan wire being for step-up idle solenoid...it to is no longer present.

As always...knowledge abounds @ CF.
Old 01-20-2014, 05:58 PM
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Mike Ward
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No C3 has a 'ceramic block' ballast resistor. The pre-HEI cars have a resistance wire.
Old 01-20-2014, 07:47 PM
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zwede
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If you can't find the resistance wire you can put an inline ballast resistor and hide it somewhere. Yes, it is needed with a points distributor.
Old 01-20-2014, 08:31 PM
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TWaldo
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Thanks for sharing...got more sleuthing to do...
Old 01-21-2014, 01:44 AM
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7T1vette
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The resistance wire (ballast) is needed IF you are installing a points-type distributor and a stock ignition coil. If you choose to install an electronic ignition module (aftermarket conversion) in that stock dizzy, you may or may not need the resistance wire; it would depend on the type of electronic module you install. Also, the coil should be compatible with the type of ignition system you install.
Old 01-21-2014, 07:44 PM
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blue427
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Do yourself a favor and call a company that sells wiring harnesses for corvettes,ask them to sell you the resistance wire from the engine harness.They should be willing to do that for a nominal charge.When you get it remove the engine harness ***,2 bolts.Remove the ignition wire that's in there and put the new wire in. Reinstall harness and you're good to go.Check you're wiring diagram for which wire it is as it's been many years since I did mine.I would be reluctant to put a ballast resister in there.If you don't get the voltage right one of 2 things will happen,1,the car won't run right,or you will burn out the points in short order.
Old 01-21-2014, 08:50 PM
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TWaldo
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Originally Posted by blue427
Do yourself a favor and call a company that sells wiring harnesses for corvettes,ask them to sell you the resistance wire from the engine harness.They should be willing to do that for a nominal charge.When you get it remove the engine harness ***,2 bolts.Remove the ignition wire that's in there and put the new wire in. Reinstall harness and you're good to go.Check you're wiring diagram for which wire it is as it's been many years since I did mine.I would be reluctant to put a ballast resister in there.If you don't get the voltage right one of 2 things will happen,1,the car won't run right,or you will burn out the points in short order.
Thanks for your input...good idea. Any vendor in mind?
Old 01-23-2014, 11:31 AM
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early shark
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Two vendors come to mind. Electric Limited or M & H electric. Both advertise in the Corvette Restorer magazine.
Old 01-23-2014, 11:42 AM
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Originally Posted by TWaldo
Thanks for your input...good idea. Any vendor in mind?
Buy new wiring harnesses from forum vendor Wilcox Corvette! Years ago when I restored my wife's 70 LT-1 I decided to can all the vehicle wiring harnesses, I got some people together to do a dealership buy from Lectric Limited and Wilcox could beat dealer direct pricing! We all ended up buying our stuff individually through Wilcox.
Old 01-23-2014, 02:23 PM
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Originally Posted by early shark
Two vendors come to mind. Electric Limited or M & H electric. Both advertise in the Corvette Restorer magazine.
Thanks, will look them up...
Old 01-24-2014, 02:17 PM
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TWaldo
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Originally Posted by early shark
Two vendors come to mind. Electric Limited or M & H electric. Both advertise in the Corvette Restorer magazine.
Contacted both by phone and neither will sell just the resistance wire. One suggested getting a donor wire from an old harness...the other suggested an "external ballast resistor" from an earlier corvette year. Not going for NCRS, just want a decent running car. Thoughts...or suggestions welcomed...Thanks Tom
Old 01-24-2014, 04:08 PM
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Originally Posted by TWaldo
Contacted both by phone and neither will sell just the resistance wire. One suggested getting a donor wire from an old harness...the other suggested an "external ballast resistor" from an earlier corvette year. Not going for NCRS, just want a decent running car. Thoughts...or suggestions welcomed...Thanks Tom
You want a decent running reliable car? Sometimes that takes a little investment. Wilcox Corvette (great guys and forum vendors) sells the Lectric Limited EXACT replacment engine wiring harness for around $200, yes, it isn't "free" but your Vettes wiring is over 40 years old now and this is the harness that takes the most beating from heat cycling. I think Wilcox even has a 10% off discout going on right about now, if you cant afford $180 to restore your Corvette back to a safe and reliable condition, I would suggest taking up a new hobby. Here is the link to Wilcox, do a search for Discount code good through the end of the month.

Link: http://willcoxcorvette.com/advanced_...php?cPath=1980

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