alternator suggestions

[6SENSE]

I have reason to believe that I need a alternator with a bit more output. Perhaps one that will at least put out what the stock 86/87s do (120amp). When my battery is at full charge things are fine. After a few weeks though seems that the alternator just cant keep up and sooner or later Im sitting at a stoplight with headlights on, brake applied, etc and scanmaster is showing mid-high 11volts. In my stock TR in the same situation voltage will still be in the 13's.
Both the battery and alternator are known good. Cables are new and good, as are other related wiring. What I think is the issue is that the car has alot of non stock electrical stuff thrown into the mix (i.e. four lighted gauges, dual electric fans, upgraded hi-power radio, alcohol injection, hotwired FP, etc along with the abundance of factory options like digital dash, electronic climate control, power everything....).
Any suggestions? I know a SBC alternator is the same, so where to get one for a decent price that isnt going to break me? I know I dont want one of those high dollar monster 200amp ones made for massive stereo systems, just something around maybe 120amp like the 86/87 cars or perhaps 140amp like the ImpalaSS?
Is there an upgrade that I can do myself with a kit?

TIA, Justin

 

[GNBeswick]

Im in the same exact boat as you.....Ive got all the same stuff you mentioned, and have too recently noticing a need for a new alternator. I know Poston used to have some upgrades....but I was unable to find them again...maybe they got rid of them. I have heard that it is possible to use an 86/87 alternator, you just have to make a new bracket for it. I remember seeing a picture of one on an 84/85 engine....but I cant remember where I saw it.

 

[6SENSE]

Yeah, the way Ive been looking at it too is that we have much more going on electrically now with these cars than the stock IC 86/87 cars, and they came with the much higher output alternators. Im sure there was good reason for that upgrade from the factory and if its just the addition of a electric fan, well, like I said weve got much more going on than that now. Heck I knew the early 3800/3.8 front wheel drive FI cars have 105amp alternators so I was always kind of worried about this becoming an issue with ours that were originally figured for a mechanical fan.
It isnt just being able to power your radio, etc. the lack of voltage at crucial times leads to KR problems.

 

[novaderrik]

i put a CS120 alt from an 88 Grand Prix withg a 2.8 V6 in my 84 T-Type. you have to use an alt with the offset mounting pattern because the CS series alts with the straight across mounting pattern like our cars had stock won't fit in the alternator bracket because the alt is too small.
you just need to make a simple adapter bracket out of a 4" long piece of 1/8" flat stock to bolt the small hole to the bracket. it's really simple.
then go to GM and get a plug for the alt and wire it up, and enjoy over 14 volts at idle with everything in the car running.

 

[GNBeswick]

You wouldnt happen to have any pictures would you?

 

[Bryan C.]

I installed a 200 amp alternator from Powermaster. I bought it from Summit Racing. It is three years old and no problems.

 

[novaderrik]

i just snapped some pics. look here- http://community.webshots.com/album/85893657cMZtDD -near the bottom of the page. i need to take my home made adapter bracket off and round the edges and paint it to make it look all pretty and factory looking, but you can see how much fabbing i had to do- i think i had 1/2 hour invested, and most of that was digging thru my junk trying to find a suitable piece of steel.

 

[V6cious]

I think that another option is to get the bracket from a na regal and get a alternator for an impala and swap the pulley with your old one I was told that these are like 130 amps

 

[John84GN]

6SENSE - I have a Powermaster 140 amp Chrome Alt. (don't know if you want chrome or not) but it was $160 shipped. The only thing I did, on my own was, I cut the #10 wire going from the battery, and installed a #4. Mainly b/c I have a LOT of electrical needs...see sig.

HTH - John

 

[6SENSE]

Originally posted by John84GN
6SENSE - I have a Powermaster 140 amp Chrome Alt. (don't know if you want chrome or not) but it was $160 shipped. The only thing I did, on my own was, I cut the #10 wire going from the battery, and installed a #4. Mainly b/c I have a LOT of electrical needs...see sig.

HTH - John

Thanks. Where did you get it?

 

[John84GN]

sorry it took so long...I'm also rebuilding my motor, in hopes for the NATS

http://www.jcwhitney.com/autoparts/...Id-100000189027/Pr-p_CATENTRY_ID:100000189027

 

[mybuick]

i used a cadillac 4.5 or 4.9 alternator. it is the same clock position and it is 190 amp and it bolts right in and has the same pully also. never had problems with it. i had on my 84 motor: hotwire kit, 6 electrical gauges, type 2 coil setup, tps tec.

 

[turbobooster]

wat yr cadillac r u talkin about?

 

[mybuick]

90's

 

[GNBeswick]

Hmmm......that cadillac alternator sounds cool. Do you know what model cars they were used on? I wonder how much they are....

 

[FlyinGN]

this is a no brainer guys. Get Mike 200 a rebuilt kit which includes everything to rebuild your stock alternator to 200a! including bearings.. $79. I did it and mines perfect now

http://www.turbobuick.com/store2/proddetail.asp?prod=TBS400
(add an 'S' after the 'K' cause this site will not allow me to type that.)

 

[mybuick]

front wheel drive eldorado, fleetwood, siville, with the 4.5 or 4.9 engine.

 

[6SENSE]

Originally posted by FlyinGN
this is a no brainer guys. Get Mike 200 a rebuilt kit which includes everything to rebuild your stock alternator to 200a! including bearings.. $79. I did it and mines perfect now

http://www.turbobuick.com/store2/proddetail.asp?prod=TBS400
(add an 'S' after the 'K' cause this site will not allow me to type that.)

Is there an upgrade that I can do myself with a kit?

Looks great, however all they mention is the 86/87 120 amp alt as the application. Will that kit fit in the bigger old school alts that we have?
Thanks, this has become a pretty informative thread.

 

[FlyinGN]

oh shoot, you are right.. I did not realize that the hot airs may have a different alternator.. darn.. sorry

 

[6SENSE]

Been looking at alternators on Summit's website. Whats the diff between GM 10si and GM 10DN? Which are ours?

Also, Im guessing that a 140amp alt rather than a 200 would be sufficient but Id like some opinions. There is a difference of a couple hundred bucks there so I want to be sure of what I actually need.
Here are electrical accessories that I can think of (Im sure some may not take much of a toll but I will list anyway):

Digital dash
Power windows
Power seat
Power trunk
Electronic touch climate control
Translator
line lock
Acell ignition coil
Scan master & sometimes laptop ran off pwr invertor
(4) lighted gauges, (2) of them w/ electric senders (h20 & oil)
Big fuel pump w/ hotwire
Progressive alcohol injection
Dual electric fans
Rear view mirror with map lights
Alarm
Power windows roll up when alarm activated
Dome light (opera and rear view mirror lights) on when alarm disarmed
Electric door poppers (shaved handles)
High power Pioneer radio
Small amp and woofer in the future

I think thats it