alternator up grade!

[Ontheboulder]

any one know if there is a difference between alternators on a big block and a small block?? Looking to upgrade my plow truck alternator,1989 chevy 1500, from 105 amp to 140 amp. found one but its for a 454 on a 1990 chevy, anybody got any ideas??

 

[CRM]

Looking on Rockauto both the 350 and 454 take the same one. Should be ok.

 

[SirRobyn0]

Looking on Rockauto both the 350 and 454 take the same one. Should be ok.

Yes this is correct. The short version is a 350 and 454 alternator will interchange no problem. And it wouldn't matter what year (well at least to a point) but anything off a square at least or van or even a car will work, but the pully my need to be swapped, for example using a V-belt driven alternator on a rig with a serpentine belt, you'd need to swap the pulley on the alternator.

Also as a side note, if your truck has a V-belt alternator running a high amp alternator sometimes causes problems with the belt squealing under high demand, for example dead battery, jump truck, the single V-belt just can't turn 140 amps worth of drag on it. And under those conditions it'll burn up the belt pretty quick. Obviously if your 87 has a serp belt that's not a concern.

 

[greyghost]

you might have to reclock it depending on where its clocked and if wiring harness will reach