i've searched but couldn't find anything. i just want to know if you can upgrade the alternator, because i've got the 7m in my 87 4runner and i'am going to be running offroad lights and all other sorts of crap.
Upgrading Alternator
- Thread starter supra4runner
- Start date
supra4runner said:
7MG has 80amp
7MGT has 100amp
Main power feed is how to id
10mm nut = 80amp
12mm nut = 100amp
Both bolt in the same
:bigthumb:
Also I heard of using the MR2 Alternator as well, and they sell 130 AMP alternators on ebaymotors for about $100 that will fit a Supra. Thats better that the toyota Price.
plaaya69 said:
Yep same alternator on the turbo SW20 Mr2's change the pulley to 7M and then its a bolt on
7M-GE = 70A 7M-GTE=80A (I can't remember if auto's had something different)
SW20 MR2's have either 90A or 100A depending on the model.
SW20 MR2's have either 90A or 100A depending on the model.
how would a higher amperage affect the car?
would the headlights be brighter, or something?
or would it just be less strain on them, and quicker to charge the battery?
is it "the higher the amperage the better" or is too high too bad, and the car explodes like in the fast and the furious?
would the headlights be brighter, or something?
or would it just be less strain on them, and quicker to charge the battery?
is it "the higher the amperage the better" or is too high too bad, and the car explodes like in the fast and the furious?
To put it simply, it represents how much power is available. It is possible to provide too much current to a circuit, but most are regulated well enough or aren't sensitive enough that you would have to worry about it with a stock automotive alternator.
BTW, there is a company here in the states which builds retro-fit alternators for imports using high output GM alternators... just can't remember the name. The prices weren't very bad either, something like a couple hundred for a 180A alt. with no core.
This isn't the company I've seen before: http://www.alternatorparts.com/Toyota_highoutput_alternators.htm
The other company modifies the housing to bolt right up and either swaps the connectors or provide an adapting harness.
BTW, there is a company here in the states which builds retro-fit alternators for imports using high output GM alternators... just can't remember the name. The prices weren't very bad either, something like a couple hundred for a 180A alt. with no core.
This isn't the company I've seen before: http://www.alternatorparts.com/Toyota_highoutput_alternators.htm
The other company modifies the housing to bolt right up and either swaps the connectors or provide an adapting harness.
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would you recommend a higher amp alternator to compensate for a smaller battery, such as a genesis?
or would it be too much?
or would it be too much?
I would recommend taking the time to make sure that any electrical drains are minimal, wiring is in good shape and it's not exhibiting signs of heavy resistance. Age is your car's biggest enemy, this goes for wiring as well. 
With that said, Genesis and Optima batteries won't charge any faster once a specific level of current is reached (See the manufacturer's datasheets for specifics. This goes for conventional lead acid batteries, but the level is typically considerably higher.).
If you're not producing enough extra current (due to add-ons such as a large stereo system or that brand new 48" plasma display in the back seat) then yes, a larger alternator will help. If you're having to charge the battery every couple days due to drainage from driving short trips and frequent starting, no, it won't help (time to get a bigger battery and start charging regularly, before you kill it).
With that said, Genesis and Optima batteries won't charge any faster once a specific level of current is reached (See the manufacturer's datasheets for specifics. This goes for conventional lead acid batteries, but the level is typically considerably higher.).
If you're not producing enough extra current (due to add-ons such as a large stereo system or that brand new 48" plasma display in the back seat) then yes, a larger alternator will help. If you're having to charge the battery every couple days due to drainage from driving short trips and frequent starting, no, it won't help (time to get a bigger battery and start charging regularly, before you kill it).
thanks for the tips guys. i will be going w/ 7mgte alternator and will be upgrading my battery to an optima blue top.
Iirc, the 89 7mgte with auto. trans. has the 100 amp alt. I was hoping it would take the stress from the elect. fans and stereo system. It's the fans that really suck a lot of power. 15+ amps on low speed, 25 on high.
Well, I couldn't find a 100A alt for the MKIII on NAPA's site, but I did find it on Champion's... they're mighty proud of that alternator. MSRP: $687.52 versus $242.72 for the 80A.
EDIT: DieHard Platinum FTW.
EDIT: DieHard Platinum FTW.
Plaaya: Yep I do and it sits for 9 months a year, couple of hours on the charger and it never fails to start
I've had it flat enough to barely light up the door lights......
(pretty tough unit)
I've had it flat enough to barely light up the door lights......
(pretty tough unit)
cuel said:
The MKIII never had a 100A alternator. The highest was 80A, and it was on all 88-92 7M-GTE's, automatic or not. Most aftermarket places only list the 80A for Automatics, but that is incorrect, Manual transmission-equipped cars also had the 80A alternator.
Jeff Lange said:
That's what I thought... the listing on Champion's site confused me... I guess for $687.52 they'll have one built.