radio interference after HEI install
Thread Starter
Instructor
Joined: Dec 2005
Posts: 127
Likes: 0
From: Gurnee Il
radio interference after HEI install
I just finished installing HEI in my '69 coupe. Now I have interference on the aftermarket radio and cd player. I did not connect the HEI to the ignition lug on the fuse block, but found a 12 volt line under the hood. Do I need some sort of shielding or change the wiring to the HEI. Any help will be appreciated.
Thanks, Ron
Thanks, Ron
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Call DragonFire. I'm sure their 'techs' will help you out. 
Also, did you change out the spark plug wires to the appropriate 'resistance' type wires? They are required for proper ignition performance and to help abate ignition noise.
Also, did you change out the spark plug wires to the appropriate 'resistance' type wires? They are required for proper ignition performance and to help abate ignition noise.
Team Owner
Joined: Feb 2002
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From: Sometimes I wonder... why is that frisbee getting bigger? Then it hits me.
Cruise-In X Veteran
St. Jude Donor '06
, Exactly what I was going to say. Make sure you get a GOOD set of wires that are shielded. Don't go out and purchase that "stock" crap from china. Go aftermarket and do a little research to see which ones work best.
Race Director
Joined: May 2003
Posts: 10,956
Likes: 409
From: California
Resistance wires are not solid wires, they are carbon impregnated center nylon wires,,,, so as the carbon breaks down the wires resistance goes up until and eventually they are junk. msd wires also have a carbon core, and a steel wire wrapped spirally around the carbon center core from one end to another, this is for RFI suppression. and lastly, solid wires... just that, a single solid wire from one end to another... no RFI suppression.
make sure your spark plug wires stay as far away from other wires as posable...
turn on your stereo, start your car, open the hood and see if a movement of wires will fix the wine... did you remove the RFI suppression capacitor from the HEI?
is the wine from the alternator or spark plugs? ignition sounds like POPS in the wine... Alternator is a smoother wine with out the POP sound...
make sure your spark plug wires stay as far away from other wires as posable...
turn on your stereo, start your car, open the hood and see if a movement of wires will fix the wine... did you remove the RFI suppression capacitor from the HEI?
is the wine from the alternator or spark plugs? ignition sounds like POPS in the wine... Alternator is a smoother wine with out the POP sound...
Last edited by pauldana; May 5, 2010 at 11:03 AM.
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Thread Starter
Instructor
Joined: Dec 2005
Posts: 127
Likes: 0
From: Gurnee Il
It's mostly a popping sound. Sorry I haven't been around lately. Been busy with other things and now have to leave town until Sunday. I'm going to check out the wire routing and connections. Thanks for all the replies and help. When I get to the bottom of the problem I'll post the results.
Ron
Ron
Intermediate
Joined: Dec 2005
Posts: 44
Likes: 0
From: Raleigh North Carolina
Hi Ron, just wondering if you were able to figure out the cause of your problems and get them fixed.
I converterted to HEI this weekend, and I'm getting the same popping noises through the stereo. I'll try cleaning up the wiring some and see if that helps. I'm also using the 8.5mm MSD spark plug wires.
I converterted to HEI this weekend, and I'm getting the same popping noises through the stereo. I'll try cleaning up the wiring some and see if that helps. I'm also using the 8.5mm MSD spark plug wires.
Thread Starter
Instructor
Joined: Dec 2005
Posts: 127
Likes: 0
From: Gurnee Il
Sorry I haven't been back for a while, My mom has been in and out of the hospital a lot. I went to Radio Shack and picked up a package of 2 clip on suppresors (sp?) and clamped one onto the power lead to the HEI. Most of the popping went away. Hope this helps.
Heel & Toe
Joined: Jul 2014
Posts: 17
Likes: 0
From: Palestine Texas
As a ham radio operator and all of the knowledge I have learned from it, most motor noise in any audio device can be corrected by grounding EVERYTHING to the frame or battery. I have even seen some fuel injectors throw some stray RF through the exhaust system! I have even grounded the exhaust pipes to the frame or the battery ground to fix it.
Race Director
Joined: Jan 2007
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From: Danville Illinois
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Resistance wires are not solid wires, they are carbon impregnated center nylon wires,,,, so as the carbon breaks down the wires resistance goes up until and eventually they are junk. msd wires also have a carbon core, and a steel wire wrapped spirally around the carbon center core from one end to another, this is for RFI suppression. and lastly, solid wires... just that, a single solid wire from one end to another... no RFI suppression.
make sure your spark plug wires stay as far away from other wires as posable...
turn on your stereo, start your car, open the hood and see if a movement of wires will fix the wine... did you remove the RFI suppression capacitor from the HEI?
is the wine from the alternator or spark plugs? ignition sounds like POPS in the wine... Alternator is a smoother wine with out the POP sound...
make sure your spark plug wires stay as far away from other wires as posable...
turn on your stereo, start your car, open the hood and see if a movement of wires will fix the wine... did you remove the RFI suppression capacitor from the HEI?
is the wine from the alternator or spark plugs? ignition sounds like POPS in the wine... Alternator is a smoother wine with out the POP sound...
Don't need no stinking radio ??
78, corvette, dragonfire, gm, hei, ignition, install, interferance, interference, interfering, noise, radio, raido, rfi, shield, stereo
