The early trucks 521? were only 28 amp (I believe) the 620 is about 35 amp. There just isn't enough room for a larger alternator on a 620. If you are willing to make an adapter and mount, any size alternator you like can be fitted on the other side of the engine below the distributor. Use the threaded bolt holes that are already there for the smog pump. My 521 bolts broke off and a friend moved the alternator to the other side and it worked just fine. I didn't need a larger alternator but there was lots of room with the L engine leaning away to the right side.
Datsun 620 Alternator upgrades + my new way
Posted 18 August 2016 - 08:19 AM
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