Grouding Stereo and amplifier on an ACR

[Schulmann]

I just installed a new stereo with a 800W amplifier on my ACR.
I have four 300W speakers with twiters and no sub.
System is great but when I start my engin I can hear the ignition.

- The stereo is using the original radio wires for +12V, ground and accesory
- My cables are prime quality
- RCA cables are nearly 1/4 thick
- RCA cables are routed along the transmission tunnel
- I also installed a 1 Farad Cond.
- Amplifier and Condansator are using the same grounding point
- Amplifier is under the seat of the passanger
- Speaker wires are far away from ampli's ground and +12V


When I first started the system I noticed a grounding issue so I rewired the amplifier's ground. The system is running much better but I can still hear the ignition a little.

Questions:

Should I install a shield behind a radio so it will protect the RCA cables from the coils ?
Should I rework my grounding again ?
What else can I do ?
Is the original radio ground is enough strong for my new stereo or should I route a new one ?

 

[Da1cop]

Looks like you may still have a ground issue! Where did you find your ground?

 

[IDWIN]

I used a seperate ground to the frame behind the battery access panel. No ignition sound whatsoever.

 

[twinturbo3150]

I just installed a new stereo with a 800W amplifier on my ACR.
I have four 300W speakers with twiters and no sub.
System is great but when I start my engin I can hear the ignition.

- The stereo is using the original radio wires for +12V, ground and accesory
- My cables are prime quality
- RCA cables are nearly 1/4 thick
- RCA cables are routed along the transmission tunnel
- I also installed a 1 Farad Cond.
- Amplifier and Condansator are using the same grounding point
- Amplifier is under the seat of the passanger
- Speaker wires are far away from ampli's ground and +12V


When I first started the system I noticed a grounding issue so I rewired the amplifier's ground. The system is running much better but I can still hear the ignition a little.

Questions:

Should I install a shield behind a radio so it will protect the RCA cables from the coils ?
Should I rework my grounding again ?
What else can I do ?
Is the original radio ground is enough strong for my new stereo or should I route a new one ?

Did you scratch away the paint for the gound point, how long is the ground, the ground should be as short as possible, 12 inches or less is good. Did you charge the 1 farad cap first before installing? How do you have your cap installed. What gauge of wire are you useing for your power and ground.

 

[Schulmann]

All power cables are gauge 4.
Their length is about 3 feet.
Yes paint was stripped from metal.
Yes Farad was fully charged.
I think it is maybe an issue with stereo ground and not with amplifier's ground.

When engin gets very hot situation gets very bad ...

 

[twinturbo3150]

take the factoy ground off the radio, your radio should still work if the antenna is plugged in, and see what that does. just to clarify the ground from the amp goes to the cap and from the cap to ground. Some people have a tendacy to run a ground from the amp to ground, and cap to ground and that can cause noise as well. .02

 

[Schulmann]

I just measured my ground from engin to various points on the body. This drives me crazy. When engin is not running ground is around 0.3ohm every where on the car.

When I start engin, this is the ground that I get:
- Engin to frame under instrument panel: 2-3 ohm
- Engin to body frame: 2-3 ohm
- Engin to Sport Bar: 10-30 ohm !!! this is one of my grounds

All right I will redo my home work ...

The sport bar seems to be sucking my ground out from the amplifier.