lights get dim??

[Grumpy]

I have a stock alternator on my 1965 Impala:
396 engine
Single electric fan
Stock Lights
MSD street fire HEI ignition (no external MSD box)
Stock radio
Heat (no ac)
3 small aftermarket gauges
That's it ( no power seats, windows, etc)
Since adding the electric fan, I've noticed a rpm drop after 10 seconds while in drive and at idle with fan on. I'm thinking its low amps at the distributor? Should I upgrade to a 100 amp alternator?
Thanks

I upgraded both my corvettes to 200 amp alternators and both the ignition and starting improved,
AND the cooling fans and head lights noticeably improved, you could use a 130 amp alternator,
look up a local alternator rebuild shop in your area I bet you can get a 130 amp-160 amp alternator built to fit your application reasonably priced locally

http://www.powerbastards.com/products.asp?cat=125887

http://garage.grumpysperformance.com/index.php?threads/testing-an-alternator.3222/#post-46703

http://garage.grumpysperformance.co...uys-don-t-look-at-the-clues.11176/#post-50124

http://forum.grumpysperformance.com/viewtopic.php?f=36&t=3222&p=8575&hilit=test+alternator#p8575

http://garage.grumpysperformance.com/index.php?threads/battery-or-alternator.10003