Alternator - what years interchange

[68jimmy]

Excuse me if this has been answered previously. I just inherited a 78 with the 350/Th350 and the alternator bearing is screaming like a banshee. What model years will work in this situation? It is the standard v-belt setup...

Thanks in advance.

[gchemist]

Upgrade to a 84-86 100 amp alternator from a Camaro.

[MARKDTN]

The 10SI and then the 12SI alternator was used from 69 into the 80s in all GM cars. It is a good alternator if you don't try to get too much power out of it. It was replaced by the CS series in the 80s. The CS130 is not a very reliable alternator. The CS144 is much better. The common "application" for these is '95-96 Caprice and Roadmaster. There is a harness available so you can plug a CS alternator in where a SI was.

Bottom line, if you just need 50-80 amps or so the SI is fine. If you have fans and big stereo you will want to jump up to a CS144. Be careful when you do this that you do not overpower the wire to the battery. Also you can't use the big alternators with factory ammeters.

[rfmaster]

Originally Posted by gchemist

Upgrade to a 84-86 100 amp alternator from a Camaro.

Your Current alternator is 62Amp 10SI
15SI from 80's camaro is a direct plug-in - bolt on.

With a little bit more work CS-144 from 90's cady will also work. CS-144 is 100+ Amp alternator with excellent low RPM current capability - real handy if you have electric fans, lights galore or a winch. CS-144 is slightly larger requiring upper bracket work, pulley needs to be swapped out (rib to V-belt) and there is a minor wiring modification (L- wire needs 150 to 300Ohm resistor and connector is different). At $25 from local pick JY it is a low cost upgrade.

//RF

[Toxic Redline]

If your looking to save money just go get one from autozone with a lifetime warranty, im still using the warranty my dad got in 85 for his k10 and we have them on all kinds of trucks, we even put them on our john deere tractors we just swapp out the pully.

[68jimmy]

Thanks for all the great info. If it warms up tomorrow I'll see what I can find.

[68jimmy]

I was able to go to the local u-pull it yard and found a 77 cadillac deville with what appeared to be a fairly new alternator. Other than than the lower bracket mounting holes it fit like a glove. And it no longer sounds like a banshee at startup...