Currently in the position of needing to rebuild my audio system and have a feeling the current (lol) alternator might not be up to the job.

I'm currently running just a class A/B 600watt rms @ 1ohm and get lighting dip on the instruments, headlights don't but I think that is xenon related? I also cut out if I go above half volume on the head unit, think that is wiring related, but will be ripping that out and rebuilding with 0AWG.

I plan on pulling all this out, swapping to around a 1200watt rms class D @ 1ohm for the sub, and a 2-channel around 100 watts rms per channel @ 4 ohms.

Considering running an extra battery in the boot but not sure if I need it, and how big it would need to be?

Does anybody know what the rating of standard alternator is on an ASZ Fab VRS and what, if any larger alternators will fit? I was looking at the 180amp from a passat if that's any help?

Sorry about all the heavy detail but need to be sure of what I'm doing here.

I think they are 95 amp as standard.

A second battery in the boot would probably help as it would reduce the power being drawn from the front one and probably reduce the effect of dimming lights etc.

I think even with a bigger alternator you may still get dipping lights etc as when the power is drawn straight from the battery the car doesn't know what load is being drawn and so can't "tell" the alternator to ramp up power output or rev the engine slightly higher to produce more power. That's why you need a capacitor or second battery to reduce the dips in power then the alternator will kick out what power it needs when the battery voltage falls.

Phil

Biggest issue is the EPS system that draws around 50 amps, so using a standard alternator with you setup is really a no no.

On my spanish fabia i have a 90amp standard alt but same engine is audi is fitted with a 120amp one as standard.

Thanks guys, I was thinking the extra battery would be needed. Sounds like trying to root around and see whats the biggest alternator I can get to fit is, I guess anything of a 1.9 should be straight swap. Can't see the point in a power cap to be honest, my mate ran with one and still fried a ground zero nuclear and then a hifonics amp.

Any specs on that battery set up in the picture? And what it was to power?

Cant remember exact details but was alot of power, cost around £2500 for all the gear and fitting.

Had somthing like 12 extra speakers and 2 x 15" subs in the boot, again cant remember spec but it was loud!!

Edited 26 December, 201213 yr by hutchysrs50

i have 120A alternator..and it is stock one