There was a listmember who retrofitted a Porsche 928 120amp alternator - I have a photo he sent somewhere.

My understanding is that with the BOSH alternators, you simply need to get one of a higher capacity, but with the correct mounting. (The part number tells you that.)
So if you find one with the same mount but a higher capacity, it should be a bolt-in proposition. I have a 120a Audi alternator that I have not yet tried. (In theory you could just swap the external case to the newer insides if you wanted to try that.)

http://jobs.boschusa.com/AutoParts/AlternatorsStarters/HighOutputAlternators/PNReferenceGuide/

Do you need a larger alternator? I don't think it would help for charging unless you are using lots of other electrical consumers at the same time. (e.g. driving lights, super stereos, the fridge on DC.)

One other thing is that there are lots of threads on the low setting of the BOSH alternator output voltage - so if you search the web you can fine drop-in adjustable voltate regulators that allow you to tailor the output voltage.

http://bartonharness.com/AdjustableVoltage.html

I have one of these on my stock Bosh alternator, it is pretty slick.

Todd
'88 westy

 -------------- Original message ----------------------
From: vw woody <vwwoody@HOTMAIL.COM>
> Does anyone know if there is a source for high output alternators for '89
> westy's. Or is 90 amps the most amps out there.
>
> Also , any of you electrical wizards know if GoWesty's deep cycle battery if
> worth the $.
>  I like the idea of not cutting up my bus.
>
> http://www.gowesty.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=PC1200&Ca
> tegory_Code=np
>
> THANKS in advance !
      woody "keep on pushin"