New alternator time and was thinking of a 140amp.

I was wanting to go with a CS130 alternator because idle charging is a problem for me. I am running a crank underdrive pulley and even with an overdrive on the alternator if I sit in traffic with the AC running the voltage drops to battery level. I think this alt is toast anyways though because at speed sometimes it looks like it's charging well and other times for no apparent reason it reads around 13 volts.

My question is what would it take to make a cs130 style alternator work with an 85 bracket setup?

 

Cs130 is a stock 105 amp model. Puts like 25 amps at idle. Are u thinking the cs144? That's what I use. Its 140 amp and a lot more durable.

 

This is the alternator I'm looking at:

www.summitracing.com/parts/pwm-48114

Do you have a better solution in mind? I'm basically looking for the best idle performance I can get.

 

i'd use an early type cs 144(used in certain mid-86 to 1993 GM cars,108 and 120a versions) exact same size and mounting as the 17si that came on '85 TPI-just will have to splice a wire or two.The later type cs144(used on certain 1990-~2002 GM cars has a slightly bulkier case but i think it will also fit-the later one i think offers up to 140a.

 

I am currently running a 12si style alternator and idle charging is a real problem especially with the radio turned up all 4 speakers amped and the blower fan on high.

I want whatever will give the best idle performance while using my existing bracket setup. I want to be done with idle charging probs once and for all.

 

does sound like there may be something wrong with that 12si(they are prone to bad stator to rectifier connections) i think a 108a cs144 would fix the problem completely-the cs series has an updated more powerful regulator as opposed to the Si type with it's late-'60s designed transistor regulator,so the CS will put out better at idle.The cs 130s do not cool well at low RPM and they overheat and fail under low RPM/high amp load conditions...For a salvaged cs144,look at ~4/86-1990 transverse engine cadillacs and other midsize transverse engine GM cars-a couple lenghtwize mounted engines that have the early cs144 include 86-87 GN and 1993 z28.

 

This is the alternator I am looking at getting:

http://m.summitracing.com/parts/pwm-47914

Currently on order til the 10th though =\