The car is a -91 745 Turbo. The alternator Bosch lists is AL 155X 100 amp, However, it came with an 80amp, (I think AL157X). Does the higher amp alt. interchange with the lower? Exempt the amperage, would there be any difference? The alt. died last night and I need the car for this evening. I can get a new one of either, but not both. Any help anyone can give is greatly appreciated, I am desperatly pressed for time.

100A Will bolt straight on.

Colin.

Thank you, it's a great help. I'm puzzled why they upped the original alt. to a larger replacement one.

The output of alternators on most cars has increased over the years to cope with the ever increasing extra load as more and more electrical gadgets are fitted. Heated seats, mirrors, higher power stereos etc. that have become standard in the last few years.
I think the 100a unit was standard on the later 740 turbos.

Colin.

Thank you for your help, I bought the 100 amp. Strangely though, when I called the dealer, they told me that the alternator they listed as replacement for the -91 740 Turbos were a 80 amp alternator, not the 100. Since overkill solves a lot of problems, I bought the higher rated alt (not from the dealer, ($300+).

When I got the old one out, turns out that the car indeed came with the 100a as original equipment.

Have a good and prosperous year.
Mans