The 150 amp. alt. will put too much load on the belt. The 6 cyl. engine has a very small contact area on the alt. pulley. The belt will squeal & glaze the belt & pully. All the late model vehicles with high amp alt. use Serpentine belts.
Most of the time the bat will not be low enough to put a large demand on the charging system, but we all know at times we leave something on for a while or it takes longer then normal to start the engine especially in cold weather or after it has set for a long period of time. That is when a large amp. flow takes place.
You might get by by over tightening the belt but that puts a stain on the water pump.
The 60 r so amp alt. is all you need for the standard accessories. The original gen put out about 30 amps & 0 or almost at idle & we drove them for many years that way.
The alt. is a tremendous improvement but there is no reason to go overboard.

George

They say money can't buy happiness. It can buy old Chevy trucks though. Same thing.
1972 Chevy c10 Cheyenne Super
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