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Alternator Upgrade Completed on 1971 BMW 2002 from 55 to 90

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I recently did a alternator upgrade, from a 55amp up to a 90amp unit. I bought a new 1988 BMW 325IX 2.5L FI 6cyl 90amp Alternator from local autozone for $130. Purchased a used upper E30 bracket(slightly larger) from forum sale.

Installed upper mount and test fit alternator to measure for lower bracket spacer that needed to be added. Made a spacer out of some round stock i had, about 3/4inch. Installed alt with pulley that came with it and found the belt was not gonna fit, so i swapped pulley with original and now belt fits fine.

Ran a fresh large wire to remote battery connection from alt and ran smaller wire for D+ to harness, secured ground wires(block and Alt). Added water(radiator has to be removed) and double checked wires then connected ground at Battery and Viola'... Putting out some serious ampS just about the best upgrade to date! Thanks Zeebuck and all others who post great write ups. Also returned a old core alt to get $50 back!

i have the 55amp alt for sale as well as the VR that goes with it if any one needs a extra.




E30 upper and Modified lower Bracket


35amp, 45amp BEEFED upto 55amps, 90amp Respectfully


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Upgrading my alternator is on the "round-tuit" list also. Were you able to remove all the wiring that went to the old VR ?( to clean up the install).

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