I had my original '69 Delco AM/FM radio restored and installed. It sounds great with the new center and kick panel speakers; that is until you start the engine. With the engine running you get an engine / alternator whine that corresponds to the level of RPM (higher RPM, higher pitched radio noise).
Noticed in the Classic Industries catalog, they have a noise suppressor and grounding straps, the description says that they should help with unwanted radio noise. Will the strap install right to the firewall from the block? Does anyone have a photo with the grounding strap installed?

Thanks,

Mark
'69 ragtop 400 4-spd

There's a page in the '68 Pontiac Service Manual that shows all the radio suspression stuff pretty well. Don't know if the '69 Manual has the same but here's the '68: http://1968firebird.org/68sm/acc/acc3.html Scroll down to Fig. 15-39

I only have an AM radio in my 69' but I believe the ground strap runs from the passenger side firewall to the head. I am trying to remember because my car is at the body shop. Hope this helps.

I have 3 ground straps...

1) Rear pass head to firewall
2) Pass frame to pass wheel well
3) Battery to body

Mine is same as Johnny Mac('68). I think it important to have all 3 connected.

Great stuff, thanks for the input. I need to add two out of the three grounds. Also the link to the service manual is very helpful.

Best,

Mark

you could add a noise supressor for a coupple of $$$ and do you have good spark plug wires because the noise is created by magnetic field ???

patvac, Do plugs make a difference too? I still use the original-type AC 44S plug and have a slight noise like Mark describes in my Hidden Audio AM/FM. I wondered if a resistor plug would reduce that??

Yes a spark plug with a built in resistor should stop you're noise look at the wires condition to!!!

Patvac,

Thanks for the input.

Do you have a brand /application for wires and plugs that you recommend?

you shoud go with delco resistor spark plug
the mfr# should start with a R before the number
exemple R44LTSM go at your local parts store.
For the wires don't go cheep!!!! no specific brand to tell you (may be taylor???)