The "Direct Fit" MR2 ALTERNATOR WRITE UP

[OneWingedAngel]

Well anyone looking for a new alternator or more beefy one, you might have heard about the MR2 alternator. I just did it today and here is my write up:

First you need an alt from a:
-1991 MR2
-2.0 Liter
-Turbo
-WITH Power steering

Damn, you can really see the size difference its gotta be twice the size of the n/a alt. I had a supra n/a alt, supra turbo alt, and the new MR2 one all lined up..its like the little baby, bigger brother and GREAT grandfather lol. Anyway its not quite so direct fit...

The plug on the back is the same, but the positive terminal is quite a bit larger, enough so that the connector wont fit over it. You will to drill it out with a 5/16 drill bit.

Next is the pulley, its different. You need to switch the two pullies over. Dont bother trying to take it off yourself if you dont have power tools, its hopeless. I took mine in to a near by shop and had them do it. Took them 1 min tops and they did it for free.

Then its squeezing time. It was like trying to shove a road cone into a virgins...well you know. Its a tight fit with that hose for the pcv running back there, and the connectors are in a lower position too, which gets in the way again with that dang pcv hose. It all works out in the end though :)

According to the paper that came with it, it has a max output of 135 amps which is significantly more than the 80 amp turbo alternators we have. But I'm happy with it and it looks good. Hope this is informative enough for those looking to do this.

[Larry_A]

Thnx for publishing a compendium on this occasionally mentioned, never quite clear topic. I've also developed a sudden envy toward road cones.
;)

[suprapimp91]

nice write up, i have been looking for a high output alt and saw the post a few days back on this subject, how much did ya pay for it, and what year mr2 will work?

[drjonez]

good to hear! 'bout time someone did a writeup...

[nottooslow]

did you take a picture of the alternators lined up? do you have any pics of it installed?
thanks.

[paddlenbike]

Thanks for taking the time to write that up. I'm interested.

What is the amperage of our alts--60 amps?

[pmpaluda]

Yeah, I'd like to see how big of a shoe horn it'll take... It worked I know, but could have the hose been re-routed?

Thx... please post pic's. And what you running for those high amp's?

[Serzy]

I wish this came up about two weeks ago before I bought a brand new rebuilt alt my supra, dangit ;)

[OneWingedAngel]

Originally posted by suprapimp91
... how much did ya pay for it, and what year mr2 will work?

I am pretty sure all 2nd gen (91-95) Mine is a 91. All the info you need is in my first post. I paid 200 after a 70 dollar core. I was wondering if they would notice that I was returning a smaller supra alternator, but they didnt.


Originally posted by nottooslow
did you take a picture of the alternators lined up? do you have any pics of it installed?
thanks.

I wish, I dont have my digicam right not, but when I get it back I will.


Originally posted by paddlenbike
What is the amperage of our alts--60 amps?

I think 80 amps.


Originally posted by pmpaluda
Yeah, I'd like to see how big of a shoe horn it'll take... It worked I know, but could have the hose been re-routed?

Thx... please post pic's. And what you running for those high amp's?

I thought about re-routing that hose, but its just too long, maybe when I have the engine out agian this summer I'll get a shorter hose and try it. I'm not really running anything that would need those high amps, but since mine went out anyway, why not upgrade it while I'm at it.

[Ratt|ehead]

Very nice...I might look into doing this.
How long did it take you to do everything? And how long would it take if u did it again?

Good stuff - I think this thread is very informative.

[TurboMK3]

Originally posted by OneWingedAngel
It was like trying to shove a road cone into a virgin..

i can't get that image out of my head

[MrBoost]

PCV? You mean the ISC or the Oil Return?

What brand unit did you get? Something like outta NAPA with the MR2 specs, or a Toyota Rebuid unit?

I think one of my hard-parts catalogs has rebuilt factory alts, hmmm. Will check! NOPI has crap like this too, I still have an acct there.

[MrBoost]

Hmmm, yeah. Just looked at my on-line w'house. They have reman units by a company called USA something. For our 80A unit, or the MR2 100A unit, they are the same price and need the core. Looks like that $200 price was very fair, It'd be tough to fight that after expenses/overhead is considered. Special order 7-12 days leadtime. Hmmm. Interesting find though!

[OneWingedAngel]

Originally posted by Ratt|ehead
...
How long did it take you to do everything? And how long would it take if u did it again?...

About 30 minutes, if I did it again, 15 maybe. Its not that bad.


Originally posted by SupraSport.com
PCV? You mean the ISC or the Oil Return?

What brand unit did you get? Something like outta NAPA with the MR2 specs, or a Toyota Rebuid unit? ...



Its that hose that runs behind the alternator from the block up to the side of the head. I assume that its for both oil return and to get the crank case gases to the head where they can be vented into the PCV system. Yea, I got this at Auto Zone, its a remanufactured unit.

[sm623cc]

ok i have a new alternator from autozone, but its for a turbo supra, im using the used toyota one now, do u think they will let me exchange it for a turbo mr2 one? if so what should i say? and also does the alternator show increase in the volt meter?

[SlimFastSupra]

don't think they won't notice.

I have been asking various places for an MR2 alternator for the last 2 years.. every time they look it up it is at least 50 bux more...

You can see in the catalogs where it shows 60-70A for our alternators and 100+A for the MR2 one.

You might be better off trying to find a used one or bear down and pay the $160.

[OneWingedAngel]

Originally posted by sm623cc
ok i have a new alternator from autozone, but its for a turbo supra, im using the used toyota one now, do u think they will let me exchange it for a turbo mr2 one? if so what should i say? and also does the alternator show increase in the volt meter?

I dont think they will let you exchange it, but you might try returning it for a full refund if you have the receipt, and then buying the MR2 one. It doesnt show an increase (unless of course your old one completly failed and you were running on only battery), as its regulated like all alternators to not exceed 14.5 volts (I think thats it).

Good luck.

[Larry_A]

Originally posted by SupraSport.com
PCV? You mean the ISC or the Oil Return?

What brand unit did you get? Something like outta NAPA with the MR2 specs, or a Toyota Rebuid unit?

I think one of my hard-parts catalogs has rebuilt factory alts, hmmm. Will check! NOPI has crap like this too, I still have an acct there.
Hello Jeff,
Although the ISC might be in the way, the hose being referred to is the cam cover hose that goes down to the fitting on the block. It starts under the oil cap, then goes straight down to a fitting that points up. That is considered a component of the PCV sys, as it is associated with the crankcase ventilation process.

You're an EE who dreams circuits...come on man!
;)

[flubyux2]

Just some FYI

Ive been pricing out reman alternators from national joints (AutoZone, parts America, Discount Auto, Western Auto)

the 1991-1992 MR2 w/ PS alternator is anywhere from $192-$198 for lifetime warranty, and higher.

The MK3 Supra Turbo alternator is anywhere from $165-$170 for lifetime warranty, of course there are more expensive ones too, but this is cheapest and still has lifetime warranty...

so if you are gonna buy a "new" reman unit w/ a lifetime warranty (lifetime warranty is smart option)... you might as well spend the extra $30 or so and get the MR2 alternator.

You can go the cheap route and get it from a Salvage yard... but i really want the lifetime replacement warranty... Just in case. ;)

[Thermactor]

Man, this is what I would go for if I didn't already have two spare 80amp alternators sitting pretty.

[conundrum07]

Since this thread has been bumped, here is a pic of it installed:

[AWIDESUPIE]

What I really want to know is where Dan Mac got his "150amp alternator". It looks just like the stock one and Dan quotes the 150ampage.

Check out this site at www.ma70.com/danmac, click on the 87T link at the top left and then scroll towards the bottom where he has a description of the alt and a link to a picture.


LMK what you guys think. I e-mailed Dan about a month or 2 ago and he hasn't replied. He used to reply to my e-mail .... I don't know why he hasn't replied to my last one.

[Bishop92T]

Dan probably got that from a stereo shop source, he used to work in that industry. He's a really busy guy so it takes him forever to reply to emails.

[AWIDESUPIE]

Originally posted by Bishop92T
Dan probably got that from a stereo shop source, he used to work in that industry. He's a really busy guy so it takes him forever to reply to emails.

Heh. I was hoping that somebody from ma70.com would reply.

If you can get any information on a PN and installation write-up ... I would really appreciate it. That is the best alt upgrade I have seen ... and it doesn't look as ugly as shawn's 150amp or the mr2 amp:D .

[Beef]

Ditto Dr J

[91T4]

Nice!

[bryanintexas]

THE TOYOTA P# FOR THE MR2 REPLACEMENT IS 27060-74180-84 ...YES IT IS A "DIRECT FIT" FOR THE MA70 W/ A LITTLE "TWEAKING" LOL ....ALSO, ON MY PULLEY, I HAD TO TAKE IT TO A MACHINE SHOP BECAUSE THE SHAFT WAS A LITTLE LARGER ON THE ORIGINAL MA70 STARTER SPEC ON THIS ALT IS 100AMPS ACCORDING TO TOYOTA. TOYOTA LIST PRICE IS AROUND $284 FOR THE UNIT.

[BoostAddctn]

If ya don't mind bro, I found this interesting and putting it in the FAQ section... aight peace :chicken:

[adjuster]

Interesting that the higher amp rated MR2 unit has less cooling fins than the 80 amp stock 7MTGE alternator..

I suppose you could coat the housing of the MR2 amp black and make it look smaller and work better due to better cooling... (Like the powermaster amps do.)

This is a nice mod if your running lots of A/M fans, and stereo equipment. I also notice at night my lights dim at idle due to amp draw with the stereo on, turn signals on, and brake lights on... Dang, throw in a rear window defroster and you really get yellow lamps at idle....

Just a few things running at night.
Headlights.
Markers
Taillights and brake lights if your on the brakes.
Signal lights if your turning.
Stereo head unit, amp(s) and the CD changer.
Overhead lamps. (If I'm lost, or have a passenger who needs to see for some reason.)
AC compressor clutch
HVAC fan and actuators.
Stock ECU.
Greddy Emanange and Profec E-01 (little glowing green screen of delight.)
Radar Detector.
Dash lights.
Fogs.
Rear defroster.
Wiper motors, front and rear if it's raining.
Washer motor if your spreading kamakazie bugs off the windshiled... Or that nifty bird deposit on the rear hatch glass...
Anyone adjust the power seat lately at night? Mine dims the lamps then too. (Try this, hit all your loads while shining your headlamps on the garage doors... Then adjust your seat while you have the blower motor on full blast with the AC running... Yellow head lamps will amaze you. The 135amp MR2 alternator might be the hot ticket for sure.)
I'm sure I'm missing something, but there are quite a few loads we are putting on the 80 amp stock alternator.

[audioman81]

where is that 150 amp alt from? was it a direct fit? the website only shows polishing it up, none of it in the engine bay.
I need a much larger alt. because my sub amp draws 100amps continous, peaking at around 120amps
thanks
Ryan

[smooth3d]

Is the max output 135 amps or 100 amps? I ask because someone above posted it as 100. Besides the max amps, how much is the idle amp output?

Great write up if I hadnt mentioned already.

[smooth3d]

Bumpalicious

[myMUSICveins]

Well, I just picked one up from Advance Auto Parts. Ill probably install it tomarrow. Ill let you guys know how it goes.

It is certainly bigger, I hope they dont notice when I try to return the core from the supra :eek:

It was $198.xx assuming they take back the core. Lifetime warrany is cool, I'm NEVER loosing this receipt :D

[smooth3d]

Originally posted by myMUSICveins
Well, I just picked one up from Advance Auto Parts. Ill probably install it tomarrow. Ill let you guys know how it goes.

It is certainly bigger, I hope they dont notice when I try to return the core from the supra :eek:

It was $198.xx assuming they take back the core. Lifetime warrany is cool, I'm NEVER loosing this receipt :D Werd, photocopy that reciept! Lemme know how that goes, I'm mad interested.

[myMUSICveins]

Well, swapped right in. In my case I only needed to swap out the pully's.

Certainly the easiest bolt on mod Ive come across aside from the Lexus AFM.

edit: Just so people know, I did not have any trouble returning my Supra core.

[smooth3d]

Originally posted by myMUSICveins
Well, swapped right in. In my case I only needed to swap out the pully's.

Certainly the easiest bolt on mod Ive come across aside from the Lexus AFM.

edit: Just so people know, I did not have any trouble returning my Supra core. I have a mechanic buddy that told me that some remanufactured alternators don't make the amperage that they claim they do. Does anyone that has one installed want to verify it by checking it with a multimeter or something?

[myMUSICveins]

I have a mechanic buddy that told me that some remanufactured alternators don't make the amperage that they claim they do. Does anyone that has one installed want to verify it by checking it with a multimeter or something?
Aftermarket alternators are indeed notorious for being crappy. @ times it can take 3 or 4 times to get a solid unit. It is not like toyota remans, where they rebuild EVERYTHING.

With aftermarket units they generally replace the one item that made the unit fail. Bearing, coil, whatever. Not a FULL rebuild.

Anyway, Ive had very good luck I suppose, Im getting 14.2-14.3 volts @ idle with my new MR2 unit.

I'll test the amerage soon.

[Kroze]

beware guys!!!

i went to autozone to order a new alternator today. there's a difference between a 91 vs 92-95 mr2 alternator.


on a 91 alternator, it saids 100amp

when i asked the guy to show me 92-95, the computer showed up 90 amps :/

good thing i check before ordering. hehe.

[Buttmunch]

Just a few quick questions. Won't changing the pully affect the amps, If they are different diamiters?? Is one pully larger than the other?? Why do you need to change the pully, different belt??

[smooth3d]

Aftermarket alternators are indeed notorious for being crappy. @ times it can take 3 or 4 times to get a solid unit. It is not like toyota remans, where they rebuild EVERYTHING.

With aftermarket units they generally replace the one item that made the unit fail. Bearing, coil, whatever. Not a FULL rebuild.

Anyway, Ive had very good luck I suppose, Im getting 14.2-14.3 volts @ idle with my new MR2 unit.

I'll test the amerage soon.Have you checked the amperage output yet?

[AllanL]

http://members.optusnet.com.au/ma71/100_0014t.jpg

both my stock alternators where like this, it was not charging at idle and only charging 20amps with increased revs

i attacked it with the dremal and soldered a wire on and it seems to be fixed :)

[myMUSICveins]

Have you checked the amperage output yet?
I should be up and running within a week, I'll check it then.

[smooth3d]

http://members.optusnet.com.au/ma71/100_0014t.jpg

both my stock alternators where like this, it was not charging at idle and only charging 20amps with increased revs

i attacked it with the dremal and soldered a wire on and it seems to be fixed :)I looked at that pic for a while, and for the life of me I can't figure out what you did! lol I see the hole you dremeled but what was the purpose of doing it?

[Boosted Supra]

I'm only able to find a 100amp ALT, what gives?

[QWIKSTRIKE]

^^^^^agreed Manny. Wzup dude

[Boosted Supra]

Nothing much, What's happening?

I purchased the 100amp ALT, anything higher cost way too much. I guess the 20 extra amp's would help.

[Boosted Supra]

Next is the pulley, its different. You need to switch the two pullies over. Dont bother trying to take it off yourself if you dont have power tools, its hopeless. I took mine in to a near by shop and had them do it. Took them 1 min tops and they did it for free.



I think not, I bought a 100amp 1991 MR2 2.0 liter Turbo w/ Power Steering. The 7MGTE ALT pulley does not fit on the MR2 ALT, the shaft of the MR2 pulley is thicker than the 7M ALT one. What do I do now?

[myMUSICveins]

I think not, I bought a 100amp 1991 MR2 2.0 liter Turbo w/ Power Steering. The 7MGTE ALT pulley does not fit on the MR2 ALT, the shaft of the MR2 pulley is thicker than the 7M ALT one. What do I do now?
Didn’t have any trouble with mine :dunno:

[Larry_A]

I think not, I bought a 100amp 1991 MR2 2.0 liter Turbo w/ Power Steering. The 7MGTE ALT pulley does not fit on the MR2 ALT, the shaft of the MR2 pulley is thicker than the 7M ALT one. What do I do now?
Hello Manny,
Unfortunately, there were at least two different part #s for MkIII alternators, & the pulley sizes were not the same on both. Early turbos & all NAs came with 70A, while '89+ turbos went to 80A.

What year MkIII is your alt from? Whichever it is, you need the pulley from the [i]other alternator in order to fit it to the MR2 alt.


Good luck, & let us know how things work out please.
;)
Take care.

[Boosted Supra]

Thanks Larry, I got the right one now. I also did the ultimate test. I turned on everything in the car, volts read at's 13.7, with old ALT it was 11 and change with just the headlights. Good upgrade

Thanks.

[Boosted Supra]

MY cousin's father-in-law owns a shop, I got the ALT from him. I told him to find out for me. You'll have to give me till the end of today, I hope.

[Boosted Supra]

OK, here's what I got in my AIM Convo:

suprafly419: they took the alt to the shop that sells the alt and they changed it
BoostedSupraMK3: I see
suprafly419: just needed the pulley size
BoostedSupraMK3: i see
suprafly419: so i took your old pulley
BoostedSupraMK3: so no idea where the 4 teeth pulley was found?
BoostedSupraMK3: shop just had I guess
suprafly419: they have them at the shop
suprafly419: they assemble and sell alt so they have all the parts

So you will have to take the pulley to the shop for measuring.

As far as mine, the belt lined up perfectly

[Boosted Supra]

I can take pics if you'd like?? Let me know

[Larry_A]

Pics won't help. Thnx anyway.

[Drew@blitzkriegmedia.com]

Hello Manny,
Unfortunately, there were at least two different part #s for MkIII alternators, & the pulley sizes were not the same on both. Early turbos & all NAs came with 70A, while '89+ turbos went to 80A.

What year MkIII is your alt from? Whichever it is, you need the pulley from the [i]other alternator in order to fit it to the MR2 alt.


Good luck, & let us know how things work out please.
;)
Take care.


So does anyone know which one you need the pully from 70A or 80A? I have an early turbo 87 (70A).

[Drew@blitzkriegmedia.com]

Hello Manny,
Unfortunately, there were at least two different part #s for MkIII alternators, & the pulley sizes were not the same on both. Early turbos & all NAs came with 70A, while '89+ turbos went to 80A.

What year MkIII is your alt from? Whichever it is, you need the pulley from the [i]other alternator in order to fit it to the MR2 alt.


Good luck, & let us know how things work out please.
;)
Take care.

Ok well mine did not fit (87 turbo). So Im taking it to a machine shop tomorrow to have the hole drilled out. However I did take some comparison pics :)

P.S. The hole for my stock pulley measures 15 mm and the hole for the mr2 pulley measures 17mm and when people say the pulleys are different sizes, they mean the mr2 pulley take a narrower belt, not that the diameter is different. Just fyi

http://www.blitzkriegmedia.com/SupraForums/top_alternators_small.jpg

http://www.blitzkriegmedia.com/SupraForums/front_alternators_small.jpg

[Disco Stu]

The alternator from my 87 n/a has the 15mm shaft. This pulley will not fit on the MR2 alt. shaft. It appears that the early cars had the 15mm shaft and the later 89+ turbos had the 17. It will probably be easier to just have it machined than try to find a pulley from a later car. Just for clarification for some that may read this thread, this upgrade is not one that will be noticed while driving if the car is already getting enough current from the stock alt. The voltmeter will still read 14.4v if the regulator and cables are in good condition unless you have it rewound by a specialist specifically for your app.