So, ever since I bought my SC3 about 2 years ago, I have had a hell of a time finding out the specs for our alternators. I have heard that they've got 80 amps, then I've heard that they've got 100 amps, and then I've heard the number 90 tossed around probably because everyone is plain-old confused and just decided to interpolate and call it a day!

Anyway, I recently bought a used '97 SC3 alt to toss on my '95 while I had the stock one rebuilt. The stock '95 alt will also be boosted to around 120 amps (I just installed the dual flex-a-lite 210 fans). The local shop is really great, and the guy that helped me out allowed me to take a peek in his spec book to find out exactly what our alternator output situation is.

I couldn't write anything down at the time, but here is what I saw:
1992 - 1994: 80 amps
Early 1995: 100 amps
Late 1995: 80amps
1996 - 2000: 80 amps

I'm sorry to say, however, that another year around '97 or '98 had 100 amps as well (but I can't remember which one). Sorry. When I go back to pick up my rebuilt '95 alt I will ask if I can see that book again.

For you 1995 guys, here's how to tell what alt you have: take off the alt (it takes like 10 minutes), and look at the back (or maybe use an angled mirror while it's on the car). If the back of the alt has 3 parallel vents, about 2" x 0.25" each, then you've the early model that has 100 amps. Anything else is just 80 amps.

Another interesting thing for early 1995 models is that the stator is rated for 120 amps, but the rotor is rated for 100 amps. The local shop is going to try replacing the rotor with one rated for 120 amps to see what happens (should technically boost output to 120 amps).

I will probably pick up the rebuilt alt in about a week, so if anyone has any questions they'd like me to resolve, now is the time and I will see if I can get them answered for you.

 

I believe the alternators for sc300's with an auto tranny have a bit more output than those with a manual tranny- but I may be wrong.

I have a pair of electric fans (they draw 20 amps EACH), so I upgraded up alternator to a high output unit- it puts out 150 amps max (compared to the 80-100amp stock alternator). It was rather inexpensive too- about $150 or so. It literally takes 5 minutes to remove/replace an alternator on these cars.. especially when that annoying shroud and clutch fan are out of the way

Allen

 

http://cgi.ebay.com/ebaymotors/TOYOT...spagenameZWDVW

That's where I got my alternator from. 3 months so far.. no issues at all.

 

what if we just "upgrade" to a higher AMP alternator.. is there any downside to that? like lets just say im not going to do anything else.. just upgrade since i need to replace it anywas.. anything wrong?

 

Woooow those are some demanding electric fans! What made you pick those ones (whichever ones they are)?

I've heard that as well, regarding the manual/automatic output differences, but the spec book at this local shop didn't say anything at all about there being a difference. It seemed to be a rather thorough piece of literature, as it had basically every make and model you could think of along with pictures of each alt... I'd personally go with the info from this book instead of hearsay.

No, there's nothing wrong with that.

 

great info, thanks !

 

Holy hell this dude finished up the alt really fast. The turn around was 2 days

Spent about $160 for the alt to be rebuilt and boosted to 120 amps, and I bought my spare '97 alt for $120 (from a 50k miles car) so after I sell the '97 it seems I'll have hardly spent any money at all (I only used the spare for like 3 days).

Anyway, a different guy was at the shop today and I didn't want to bug him about getting out that spec book. But, if any of you 97 or 98-ish owners are interested to see what the actual amperage is (see my first post), then just give this shop a call and ask for Blair. Super helpful and knowledgeable guy. It's Motor Electric in Grass Valley, CA.

 

where can i get an alternator with 120amp? also how much?

 

Ive seen up to 160 amps on ebay for 160 or so

 

i need a high output alternator, will that same one work for my 99? did you have to upgrade anything else?

 

Might have to upgrade the alternator wire when running a higher amp alternator.
http://www.lextreme.com/allgo.html

 

FWIW

the supras alternators are rated at:

Turbo 6spd - 90amp
Turbo Auto - 100amp
NA 5spd - 90amp
NA Auto - ?? 90 or 100amp

and they are all interchangeable w/sc300's

I dont know why they would use 80amp alts with the sc's. The lexus has more electronics vs the supra

 

I think I need to replace my alternator on my 92 SC300, looks like the OEM one is like 80-90amps. Would it hurt to replaced it with an180amp one ??

 

ha, i just read the first post in this thread, went to ebay, found that 180 amp alternator, flagged it and came back to read the rest and here you just posted it ha.

 

yeah that 180 amp alternator is kinda tempting...
Has anyone bought any of these 180+ amp alternators and experienced any problems?