472 hei risistor wire

MrWellman · #1 (**permalink**) 02-19-09, 10:11 PM

I'm converting my 70 coupe with a 472 to hei, I already did my homework and read all the post on this subject. However, here is my problem. When I got ready to run my new 12volt supply my buddy walked over and ask why I was running a new wire. I explained that the wire was a risistor wire and the Hei require a full 12 volt line. He said bull u know what. Next thing you you know we where placing a bet. So I whip out the volt meter, getting ready to collect my $20, and to my suprise the meter read 12v. I hate looseing a bet.

cadillac_al · #2 (**permalink**) 02-20-09, 10:38 AM

I hope a real electrician will straighten this out. I have seen HEI's run with that resistor wire but I always bypassed it. OK...........this link does say that the resistance wire goes to 7 volts or so after starting. Maybe it does have 12 volts when you just turn the key on.

http://www.hemmings.com/mus/stories/...feature19.html

submariner409 · #3 (**permalink**) 02-20-09, 11:33 AM

Yep......Quite a few ignition systems using ballast or resistor setups have 12V at key on - start, but revert to 6.5 - 8 volts in RUN to prevent coil overheating.

It would be interesting to check the voltages at START and RUN. Also, find out if your Mallory, Pertronix, ACCEL, whatever distributor does, in fact, require a ballast.

Different cat, but my Olds 455 boat engines run Pertronix modules in the distributor, and they start on 12 volts and run on 8. (2 wires from the ignition switch, one start, the other run, duh!)

MrWellman · #4 (**permalink**) 02-20-09, 01:52 PM

The hei is a stock model off a later Cadillac, The new wire is getting ran no matter what, in fact I would have already done if we would not have goten into this pecker measureing contest. Any way we did some more testing just for the fun of it. The car has a wire from the cranking circuit that puts out what ever the battery puts out while cranking. When the key goes back into run, than wire goes to 0. The ristor wire while the car is running does seam to restrict the juice to about 3 volts less than the rest of the system, around 10.5-12.5 depending on rpm. Maybe its 12v ristrictor wire, but surely not the low voltage everyone seems to warn about. Any way I pernapped-finished leather, or a variety of fabrics with a brushed finishd him to buy some bear with his winnings and made sure I helped disposed of it, sure would of been nice to have that W though.

MrWellman · #5 (**permalink**) 02-20-09, 04:58 PM

Believe me I did not type that last line about the leather and fabric, I have no clue how that ended up in there.

drmenard · #6 (**permalink**) 02-21-09, 01:32 PM

The resistor is not going to drop the voltage until the circut is complete.To prove yourself right take your old coil and take the neg side and ground it to the block now connect the dis. wire to the coil.... now check your voltage.. then do the same thing ith your new 12 volt wire..you will now see how much of a voltage drop you get with the resistor in the wire...