The Big 3

[Audiomechanic]

So, for those of you who have done the big 3, where did you connect your upgraded cables? Battery to chassis ground, battery to engine ground and alternator to battery positive.

In the Bently's, it says there is an engine ground on the cylinder head of the 1.8T near the ignition coil. i found no such ground. I do know that the main engine to battery (or chassis...wherever the heck it goes) ground it mounted to the transmission, not the engine. I was thinking of adding a separate 8ga connection between one of the closest valve cover bolts and the battery negative. Should have a more solid connection than factory, especially since I've been told the factory ground has a tendency to work loose from the tranny.

Is it necessary to upgrade alternator hot to battery positive? Cable seems pretty large as it is, just looks like the grounds need help.

I'm not going to need to go higher than 8ga because the sub I'm looking to run is crazy efficient and won't require much power at all (120 watt amp would be plenty).

[Toad]

Unless your running major power, you don't need to upgrade you grounds...

Just run the positive cable from the battery on back, then ground the amp to the chassis. I was running a 75x4 and 280x1 amps in my beetle without upgrading the factory wiring, running a 4ga wire to the back to a distribution block and 8ga from there. I only needed a half farad cap to keep the lights from dimming.

If you want, id suggest getting a deep cycle battery before going crazy with bigger wiring coming form it. But with only a sub amp. its not really necessary unless you want music with the car off for a few hours.

[Audiomechanic]

Originally Posted by Toad

Unless your running major power, you don't need to upgrade you grounds...

Just run the positive cable from the battery on back, then ground the amp to the chassis. I was running a 75x4 and 280x1 amps in my beetle without upgrading the factory wiring, running a 4ga wire to the back to a distribution block and 8ga from there. I only needed a half farad cap to keep the lights from dimming.

If you want, id suggest getting a deep cycle battery before going crazy with bigger wiring coming form it. But with only a sub amp. its not really necessary unless you want music with the car off for a few hours.

I'm definitely not going to be running major power. The sub I want to run is crazy efficient and will require no more than a little 120W amp. I might also add a 6 channel amp for the a-pillar tweets, doors, and rears instead of running them off the head, but there again, won't need 1000 watts of power. Maybe a couple hundred tops.

I might still add an engine ground from the cylinder head to the battery. Reason being is to try and get rid of the ignition noise when listening to AM. I'm pretty positive it's a loose ground causing it because sometimes the interference is not there, but then I hit a bump in the road and it's suddenly there and drowns out the content. Very annoying.

Thanks for the tips, Toad!!!