100 AMP Alternator

[Big Blue]

Looking to replace my 63 amp alternator with a 100 amp alternator with V belts. Can I get one that will fit right into the stock brackets and bolt holes? I plan on running an electric fan. That should be the only draw on the system other then the normal things. The parts guy said i'll have to modify my brackets and maybe drill holes for the bolt. Thanks ,John

[my56chevytruck]

Originally Posted by Big Blue

Looking to replace my 63 amp alternator with a 100 amp alternator with V belts. Can I get one that will fit right into the stock brackets and bolt holes? I plan on running an electric fan. That should be the only draw on the system other then the normal things. The parts guy said i'll have to modify my brackets and maybe drill holes for the bolt. Thanks ,John

John,
I can't say for 100% fact, but I do believe as long as they are the same brand they should bolt up the same, BUT, are you upgrading your wiring? It would be my guess you'll need a larger gauge wire to the alternator than what you have now.

[Dead Parrot]

If you are willing to settle for a 94 amp, then you can buy a drop in replacement assuming your current one is a 10SI.

Site with lots of info on subject: http://www.madelectrical.com/electri...elcoremy.shtml

[gmachinz]

If you want to upgrade to a CS alternator, grab one for a 1988 Olds Firenza 2.0 FI and swap pulleys. You will need to upgrade the wiring but its worth upgrading to a 90A CS vs a 100A SI because the CS alternator voltage regulator has a much faster response to changes in voltage fluctuations than the SI variety.

[truckin 79]

I just switched alternators in my Trans Am because I needed more amps at idle for AC and blower fan. Google 10si to CS130 and you will find plenty of info. The power windows going up and down would draw a lot of amps and you could see needle visibly move on voltage gauge. You need to buy a conversion wire 12.00 and then find a cs130 alternator which I found for 50 bucks 105 amps. I did not change any wires since alternator only puts out what vehicle needs and the wiring in TA is in good shape. The new alternator just laughs at amp draw of windows going up and down now. Best upgrade I made to the TA but dont think my truck will need this upgrade for a while.
https://www.hemmings.com/magazine/hm...s/3728021.html

[Jake Wade]

I put one of these on my '85, worked great!

https://www.summitracing.com/parts/s...olet/model/c10

[Big Blue]

WHOW,YOU GUS ARE GREAT. I did not plan on upgrading my wire. But if I have to then I will. It looks like the one from Summit is the one I can use. If I go that route do I still have to upgrade the wire? And the 94 one sounds like one I can use if I go also. I failed to mention that I will be putting electric door lock s and windows as well as a electric fan system. So I would like more amp then less. Again thanks for the great information and the quick response to my Question. That's why I stay here and learn.

Thanks John

[gmachinz]

This is merely another option: I like to convert to a GM serpentine swap as seen in one pic and with that kit, I can add my 140A CS144 alternator adapter bracket kit to it to allow this massive alternator. I prefer tonuse the 94-97 Impala sS versions with my HD bracket kit. The stock setup is my father in laws 77 while the 140A alt is on my 86 K10 but I posted both pics to show a stock setup and an upgraded one.

[Big Blue]

Thanks gmachinz, I plan on doing just that, adding a serpentine system after I get then engine running. This is my project that is in my signature below. I want to make sure that everything is up and running before I complete the build. When that time comes I will be asking more question on how to set up a Serpentine belt system. Stick around I my need you.
John