MSD6A & radio noise problem

[Jack21]

While deglitching the rich running Holley and CR muffler swapout, I replaced the Accel 300+ CD ignition & FMS plug wires with an MSD6A & MSD low resistance plug wires. (Just on the offchance that part of the plug fouling might be caused by the ignition).

Turns out that when I replaced the mufflers, I was able to tune the Holley. (Opened the secondary butterflies a little, colsed the primaries enough to get out of the primary transition slot, and stopped fouling plugs at idle). Accel ignition was probably OK.

When I installed the Accel ignition box, I installed a radio noise filter at the radio power lead along with it. No radio or tape deck noise. The MSD has a distinct (and annoying) Bzzzzz, even with the volume turned down, and increases in pitch as the RPM goes up. Using MSD distributor with mag pickup, Accel coil.

Any ideas on what might be causing this, and how to cure it? Otherwise, I have to put up with the noise, or put the Accel CD box back in.

I know, I know; why do I want a sterio in a Cobra at all??? I like my Oldies tapes and stations sometimes! And I like it loud! '50's & '60's stuff. Chuck Berry, Little Richard, Bill Haley & the Comets, yeah that stuff.

[Roscoe]

Let me suggest that you trace the radio wires and find the big red one that is the power line. Cut it and you will not have the problem anymore.

Roscoe

ROSCOE,

YOU ARE COLD. I LOVE IT, MAN - - "NO SLACK FOR NOBODY"

JACK, IF YOUR GETTING THE SAME RESPONSE WITH THE VOLUME "ALL THE WAY DOWN" YOU ARE PROBABLY PICKING UP THE INTERFERENCE AT THE I. F. (INTERMEDIATE FREQUENCY) STAGE. THIS IS TYPICALLY 10.7 MHZ. YOU MAY HAVE A I.F. OUTPUT ACCESS ON YOU RADIO (ABOUT 20% WILL HAVE IT) OTHERWISE YOU CAN GET A SCHEMATIC OF THE RADIO. AND THE I.F. PORTION WILL BE NOTED . YOU MAY HAVE TO INSTALL A FILTER AT THAT POINT WITH A CONDENSER TO CHASSIS GROUND. (THAT'S "RADIO CHASSIS" BY THE WAY).

ALTERNATIVELY, ROSCOE'S IDEA IS A "SURE FIX".

CALL ME IF YOU HAVE ANY QUESTIONS.

BLACKJACK (aka SUNDANCE, ON THE CACC SITE).

[Back in Black]

Blackjack has a good possible solution. The right filter in the right place should help.
I have just shipped a $2,000 stereo system to my manufacturer, for install in my West Coast cobra...I will list the goodies here to tweak those who despise one of the great joys in motoring...MUSIC!

Eclipse in dash cassette with CD controller system, with remote controller (like a VCR remote)

600 watt multi channel amp in trunk

(2) Eclipse 8 CD stacks/players in the trunk

(2) MB Quart tweeters in the doors

(2) MB Quart midrange 5 inch round speakers in the doors

(1) 8 inch sub woofer mounted in the back wall at shoulder level, between the seats

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Big improvements in stereo systems recently, make actually hearing the stereo at speed , a possibility, vs the older systems many have or may be aware of. A nice accessory for the passenger is a set of plug in stereo headphones, cuts out all other sounds, let's them (rock) (oldie) (whatever) out.

[HighPlainsDrifter]

Jack21;
MSD has a capacitor that they call a noise filter.You put it in parrallel with the main red power lead to the msd box. Not only a good idea for the radio but a must have for voltage spikes to the msd electronics. People claim that they have never had a msd fail with that capacitor in the circuit.
Perry.

[Jack21]

I admit, a Cobra is not an acoustically friendly environment for a sterio, but there are times when I just like it. Doubt I have even $200 tied up in it, speakers (Infinity), amp (Legacy), and deck (JVC). soundomain.com has good prices.

Hey, I did cut the big red wire, and now nothing works. Now what do I do???

Will check into that MSD noise filter. Thanks.

[Rick Parker]

Before you do anything drastic just try changing the plug wires to some with a higher ohm rating which will often "choke" the static to the point that it can't be heard. The Red MSD wires have a spiral wrap that helps eliminate magnetic fields that effect the electronics of some components but often times depending on application will not cancel out the spark plug firing. Also put a small dab of dielectric grease (clear) on the tip of the rotor and on the sparkplug boot to form a weather tight fit and aid in their removal after heat cycling. Sometimes these types of problems are obvious but we tend to overlook them while chasing something more complex. Just a thought.......

Rick......

I like to tune the volumne on my stereo and adjust the static WITH MY RIGHT FOOT!

[Frank Coppola]

I have been staring at this post debating on whether or whether not to comment. I just can't resist:

YOU NEED A BIGGER MOTOR if you can hear static in your stereo, let alone sound from it period.

Roscoe said it best in another post.

Left side pipe= left speaker
Right side pipe= right speaker


-I feel much better now, thank you.

[wicked fast]

them pipes,
them pipes,
wait until the kids see the pipes!!!
Bill Cosby at 200 mph

You don't need no stinkin' radio in a Cobra.

[Jack21]

You guys in Joisey got supm against Rock& Roll? Huh? I like it, and she likes it, so my motor's big enough.

Granted, over about 35 MPH, I turn it off cause I can't hear it anyway. But DC might as well be Exit 16 without the toll at 0 - 10 MPH. And I like my oldies w/o static.

Got the MSD ignition cap, and another Accel cap for the amp. See how it sounds after install.

But this is where the static police quits the chase, and lives with what's left. The MSD seems to do a better job at what it was designed to do than the Accel did. Engine doesn't skip a beat. Now with decent flowing sidepipe mufflers, and a better tuned Holley, the car runs better.

Time to cruise.

[Back in Black]

Turn up your stereo enough and you won't even hear all those old folks complaining

I will have the 514 bracket race motor, and I will be able to hear the stereo...I will not hesitate to use stealth earphones either, if needed !

[Jack21]

Static is gone. MSD cap on box, Accel cap on amp did the trick. Nice & clean now.

A word of caution on that MSD cap though. A capacitor that size can store a lot of kick. Even with the power off, it stays charged, and will knock you on your a*s, as if you'd grabbed a plug wire.

Thanks to all with suggestions, and pureists who don't need no steenkin sterio in your Cobra.