[JohnTN]

I am building a street rod with a mild Olds 350 engine (carbureted with no computer) and plan to replace the stock 78 amp alternator with a polished one, but not sure if I need to increase capacity.

The stock engine was cooled by an engine driven fan. I will replace that with one 2670 cfm fan that draws about 25 amps I think. Will also have AC and typical off the shelf stereo system (25 watts x 4).

Initally no power windows or locks or cruise control, but those might be added later.

I would think the stock alternator capacity would be adequate except for the addition of electric fan.

Do I need any more capacity than 78 amps?

John

[AngliaBob]

John,

I am running 2 electric fans and a trans cooler fan, power windows and a normal stereo. I had a 63 amp alternator, but it wasn't keeping up the charge. I bought a 100 amp alternator to replace the 63. If you are going to be buying a new alternator, I would suggest going for the 100 amp.

AngliaBob

[julmer]

If you are buying new, it should not be much additional for a higher capacity unit. If you go stock size now and later find you need a bigger one, you are out the cost of the stock one. If you go big now, it will not hurt you in any way now and you are ready for anything that comes up like you discover you want or need a second fan or a boomer stereo.