Classic Retrofit's high output alternator developed in conjunction with WOS Performance is the ONLY alternator available for the 911 that can deliver a continuous current in excess of 100A. The alternator can deliver 75A at idle.
The design uses all new 6 phase internals inside a billet alloy casing that bolts into the 911 fan housing. It is a direct fit to early cars and requires spacers to fit mid and later years.
Other 'rewound' alternators claim high output but cannot reject the heat generated by the windings for a sustained period.