Ignition interference
Thread Starter
Pro
Joined: Jun 2002
Posts: 538
Likes: 7
From: Johnsonville Wi
Ignition interference
I have just installed new plug wires (hand trimmed universal set). Taylor Pro series Spiro RFI, and now have AM radio interferance
I'll be as breif as possible:
I have 2 cars that are very similar - an '86 Fiero V-8 conversion and a 1964 Corvette. Each has a GMPP HEI distributor. Both run The same Taylor wires and "Crossfire" caps. Neither has any spark ignition problems
The Fiero has no interferance, the Corvette now does.
I've had the 'Vette for 20 years and it has had many different ignition wire sets on it, from the orignal points setup to 2 diff. HEI's, never any interferance.
The Taylor sets used are #73253 and #73251 - only diff. is the plug end angles.
I may swap caps, as the wiring setup is the same for both cars to see if it's a cap issue, but that's a stretch.
Anyone with any other thoughts?
BTW both cars have aftermarket stereos, both have very good basic wiring, both have good antennas - and remember that there was no problem until the wiring / cap change.
Could this be a bad / mismarked set of RFI labeled plug wires?
I know that I need to try to isolate this with cap/wire swaps but I'm asking on the chance that I'm missing something obvious.
Lusox
I'll be as breif as possible:
I have 2 cars that are very similar - an '86 Fiero V-8 conversion and a 1964 Corvette. Each has a GMPP HEI distributor. Both run The same Taylor wires and "Crossfire" caps. Neither has any spark ignition problems
The Fiero has no interferance, the Corvette now does.
I've had the 'Vette for 20 years and it has had many different ignition wire sets on it, from the orignal points setup to 2 diff. HEI's, never any interferance.
The Taylor sets used are #73253 and #73251 - only diff. is the plug end angles.
I may swap caps, as the wiring setup is the same for both cars to see if it's a cap issue, but that's a stretch.
Anyone with any other thoughts?
BTW both cars have aftermarket stereos, both have very good basic wiring, both have good antennas - and remember that there was no problem until the wiring / cap change.
Could this be a bad / mismarked set of RFI labeled plug wires?
I know that I need to try to isolate this with cap/wire swaps but I'm asking on the chance that I'm missing something obvious.
Lusox
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From: Canada's capital
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Put the old wires back on and see if that's it. Could be the plastic body being the difference between cars. You can put a radio interference resister on like old cars had that used solid wire core wires. There's nothing on the radio worth hearing anyway! 
Le Mans Master
Joined: Oct 2000
Posts: 8,897
Likes: 1,356
From: Santa Ana CA
Well, not on AM anyway. 
Ergo, I tolerate this AM noise on my '64 in the interest of additional hp. (Solid copper plug wires and non-resistor plugs with only a top shield in place let me, and those around me, enjoy my ignition.)
Ergo, I tolerate this AM noise on my '64 in the interest of additional hp. (Solid copper plug wires and non-resistor plugs with only a top shield in place let me, and those around me, enjoy my ignition.)
Safety Car
Joined: Mar 2009
Posts: 4,191
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From: Corpus Christi, TX
Spiral core wires have low enough resistance to get AM radio interference in a plastic Vette. Your metal Fiero will shield the residual RFI from the spiral core wires. The factory wires have graphite impregnated fiberglass cores that have such high resistance you get very little RFI from them.
Thread Starter
Pro
Joined: Jun 2002
Posts: 538
Likes: 7
From: Johnsonville Wi
Radio Int.
Thanks for the responses. Kerrmudgeon, I can put the original parts back but I know what I'll get: no radio interferance and a light show under the hood at night with missing. Tell me more about adding a resistor, where would I wire this? My car has a relatively new main wiring harness and I think that I have all of the original capacitors in the the correct places.
Daffy2
Daffy2
Le Mans Master
Joined: Nov 2008
Posts: 5,691
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From: columbus oh
i have a friend that received a ticket for noise pollution, running solid wires, two years ago when he pulled up to a stop light next to a sheriff's criuser and wham....the lights started flashing!!
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From: CT
Le Mans Master
Joined: Nov 2008
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From: columbus oh
all i know is it happened in gahanna ohio... the noise from the plug wires caused interference in the police radio .....suppression wiring and ignition systems came into play many years ago to stop interference for garage door openers tv sets, radios and communication devices....im not sure about aircraft maybe someone else will chime in.....
Race Director
Joined: Feb 2004
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From: CT
all i know is it happened in gahanna ohio... the noise from the plug wires caused interference in the police radio .....suppression wiring and ignition systems came into play many years ago to stop interference for garage door openers tv sets, radios and communication devices....im not sure about aircraft maybe someone else will chime in.....
Le Mans Master
Joined: Oct 2000
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Likes: 1,356
From: Santa Ana CA
Thanks for the advise. I'll try to stay away from the donut shops..., except for Donut Derelects.
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Daffy2, I can't remember the exact connections, but I think it looked like a ign. condenser and usually attached to the distributor or generator. Some other old tech head may be able to fill in the details, but they worked well. Rob out.
Rob out.
Le Mans Master
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From: columbus oh
Safety Car
Joined: Mar 2009
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From: Corpus Christi, TX
Even if the only non-solid core wire you run is the coil to distributor wire, don't run all solid core wires on you street driven car. The same physical property of solid core wires that makes them effective (close to zero resistance) causes huge voltages to be induced in the primary side of your ignition system when the coil discharges. They will fry most electronic ignition systems not specially built in a few minutes. I learned this lesson the hard way when the Unilite module was first released in the late 70s. I burned up four of 'em before at least putting a spiral core wire on the coil.
Le Mans Master
Joined: Oct 2000
Posts: 8,897
Likes: 1,356
From: Santa Ana CA
They're not outlawed, they just create so much radio frequency interference you might just get the FCC called on you, if not the cops.
Even if the only non-solid core wire you run is the coil to distributor wire, don't run all solid core wires on you street driven car. The same physical property of solid core wires that makes them effective (close to zero resistance) causes huge voltages to be induced in the primary side of your ignition system when the coil discharges. They will fry most electronic ignition systems not specially built in a few minutes. I learned this lesson the hard way when the Unilite module was first released in the late 70s. I burned up four of 'em before at least putting a spiral core wire on the coil.
Even if the only non-solid core wire you run is the coil to distributor wire, don't run all solid core wires on you street driven car. The same physical property of solid core wires that makes them effective (close to zero resistance) causes huge voltages to be induced in the primary side of your ignition system when the coil discharges. They will fry most electronic ignition systems not specially built in a few minutes. I learned this lesson the hard way when the Unilite module was first released in the late 70s. I burned up four of 'em before at least putting a spiral core wire on the coil.
Instructor
Joined: May 2006
Posts: 211
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From: N. Tustin Ca
you can use " choke coils " ("toriods") round iorn ring that you loop the power lead in and out of just before the radio, and/Or an RC filter (resistor/capacitor) also on the power in lead. You also want a good ground wire to your radio with a toroid. You can also find a better quality antenna cable (better shileding)
Use the above and should get no noise an AM. Check them out online!
Yes, I know it's just that I work with RF noise problems for a living in medical equipment
( MRI's and CAT scanners)
Use the above and should get no noise an AM. Check them out online!
Yes, I know it's just that I work with RF noise problems for a living in medical equipment
( MRI's and CAT scanners)
