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Alternator - which would you choose?

FlyingEagle

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Mar 5, 2005
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I know the old adage and have seen guys write horror stories about local rebuilds not lasting, nor cheap part store units lasting under the heat of any Mitsu turbocharged engine bay, so I pose this question:

Would you:

click for Ebay advert

Or could you:

Click for 2.4L Expo alternator ad on Ebay

Some of the alternator listings are compatible with most 4g6X equipped cars due to identical mounting options, but what is the full list of alternators that can be 100% plug and play with the following:

4g61/t
or
1G 4g63t 6 bolt bracketry and chassis plug in?

I'm fitting this into an 89 Mirage/Colt, but it's a twin (in shape) in this regard to the GVR4, only the stock output of the alternator was a mere 75 amps versus the 90amps for the Galant.

I'm wondering what the highest output, factory output for an alternator in similar Mitsu products has been, that received the same clocking/mounting shapes for bolts and tensioning, or that could have a case swap performed and achieve the same purpose.
There has to be another answer for a great long life genuine Mitsu product versus the GM alternator approach. I would fear a GM alternator at high RPMs ..... for any length of time. Just my preference, no evidence to support this.

I do have set of exhaust covers installed, and would like to figure out a way for some venting to the alternator .... not interested in mounting the alternator on the rear of the block. I have a Cyclone and AC ... not going that route.
 
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iceman69510

Turn Right Racing
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I might. Question is, do you need that many amps, and is the price reasonable if you do?
 

FlyingEagle

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I have been looking at fans from a reputable supplier on Ebay, as directed to by a long time go fast Mitsu guy.
I am concerned about drain at idle ... most specifically our type of alternator is only efficient as the RPMs rise, by design.
The GM's make more amps at a lower RPM.
Tri Y versus the other style, the types elude me as this was schooled into me years ago. Maybe I'm totally off, but it was an import preference versus domestic preference for how they worked when
I was learning about them.

I like the idea of voltage stability at idle and lower RPM's because that is where 99% of issues are to arise when you drive. Hot, stop and go ... prolonged idling with fans kicking on/off, AC switching, dash lighting, and any gizmos plugged into the matrix that will drain things down, voltage wise. Heck, even the signal lighting causes my dash volt meter to swing!

I have a thick 2 AWG starter and 4 AWG alternator rewire to the trunk mounted battery and no voltage sag ... but I do suspect I will run out of amperage and the corresponding drop in voltage, at some point.

It would be best to have extra amperage on tap, because you can't make it appear out of thin air. Now more amperage could come at the cost of more heat in the alternator? Yes?

So, it's a two fold attack scenario.

Have more on tap, but be able to cool it, should it come to it.

I guess I should mention that the fans being installed are supposed to be rated at 2250 CFM, 200 watts.

One fan will be a puller mounted in front of the trans side of the radiator, the other will be condenser side, pusher. Currently I only have a single stock fan at the trans side ...AC fan missing. Never got it with the car, I do not run the AC except on the highway.

There will need to a buffer for current, when both fans kick in and any other accessories are on. We all know the low voltage the alternators achieve with a few things turned on, then tax them.
I am trying to establish current at turn-on, and steady state.

I tore out the antiquated stereo system the car came with ... for now. I now get to see the minty fresh spare tire for the first time in nearly half a decade. /ubbthreads/images/graemlins/devil.gif

Long winded post, but figure there may have been some changes or updates since I last looked into this type of thing.

Here are the fans:
click
 
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FlyingEagle

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THE Ottawa
To answer your question Iceman, I would pay a reasonable price if longevity of the part is assured, and the system would never really get taxed.

I see the rewinds sometimes list that they don't achieve maximum until a certain elevated RPM, but if they achieve more than a stock alternator or are well above
the highest stock amperage a Mitsu alternator will put out, then it is a better deal IMHO.

I guess that unless a rewind is going to put out a mere 10amps more at idle than a stock unit, it would not be that great a deal, nor worth the pennies you would pay for it.

Maybe I'm overworking my mind.

I spin circles sitting here thinking about what to do with my car, versus circles in parking lots.
 

donniekak

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Jan 1, 2009
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surprise az
The real issue with our alternators would be fixed with this. Not that higher output wouldn't be nice. But the internal electronics are why 4g63's eat alternators.
click
 

G

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I would go with a bosch 90 amp. click I'm going to give an example of the complete opposite experience about anything anyone says, in turbowop fashion. "I'm still on my OE stock alternator & it still works fine" /ubbthreads/images/graemlins/dunno.gif No seriously I am. I believe bosch also has a 120 or 140 amp unit for the vr4 but I have to look up the part # in my bosch catalog at my office.
 

turbowop

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Yakima, WA
Bosch stopped making *new* 90 amp GVR4 alternators as far as I know, unfortunately. The alternator I have now is a Bosch DSM unit, which puts out less amps, but seems to still work just fine. It was worth getting the new, lower amp one for the lifetime warranty and the two years worth of free towing if the alternator died. So far I've had great luck with Bosch units. It's been awhile so I'm not sure what they offer as far as warranty anymore.
 

EfiniX

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portland, or
Whatever you buy,make sure you have a heat shield. I don't care what alternator you have, the heat coming off the down pipe will cook the regulator.
 

EMX5636

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Jun 28, 2008
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Location
Bucks County, PA
Saturn Alternator. Mines been in there since I built the car, right next to a 3" downpipe, no issues. The SC2 has almost a 7k rev limit anyway, so it's not much different than an OEM 4G63. For what it's worth, I run mine to 8500 on the regular.
 
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christo

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Feb 7, 2003
Messages
201
Location
Fairhope, AL
I purchased an ACE 140 amp unit many years ago, maybe 5-6 IIRC.

It has been doing well for me, I don't daily my car and I also have it relocated to the back side of the motor which has a lot less heat so that also plays a big part in longevity.
 

Coltsfan

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May 4, 2014
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Tonawanda
I had two of those 140A ace alternators, and neither lasted more than a month. I assumed it was RPM related, because they both died at racetracks. Could have been heat though. I ended up putting a Camaro alternator in my Colt (same as Saturn but even cheaper) and the car has been running at 14.4 volts for years now.
 

donniekak

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surprise az
Quoting EfiniX:
Whatever you buy,make sure you have a heat shield. I don't care what alternator you have, the heat coming off the down pipe will cook the regulator.



Or buy one of these and move the rectifier away from the heat.
click
 

FlyingEagle

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Mar 5, 2005
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Quoting G:
I would go with a bosch 90 amp. click I'm going to give an example of the complete opposite experience about anything anyone says, in turbowop fashion. "I'm still on my OE stock alternator & it still works fine" /ubbthreads/images/graemlins/dunno.gif No seriously I am. I believe bosch also has a 120 or 140 amp unit for the vr4 but I have to look up the part # in my bosch catalog at my office.



A part number would be great. Although it is not likely to hit in Canada, on the usual parts suppliers, likely because we never saw the VR4 on this side of the border. Now, that is not to say that Bosch is or couldn't offer up anything from their catalogue regardless of location in North America. I part # would be great.

I currently am running a likely 75 amp unit of some sort ... DSM, Colt/Mirage 1.6L ... not sure. No part number left on it, could be a reman because it was a replacement pulled from a Talon we parted.

I have a stock 75 amp unit needing brushes, as it was otherwise functioning properly and only died a low spring contact to stator ring type death.

If 90 amp units are fine, then maybe I should simply lead myself there and consider some options.

Liking the link the was supplied for the external diode rectifier bridge assembly ... from 6 to 18 diodes, holy heck batman!

I have induced wicked AC noise into my system somewhere, but I could only tell with the stereo on, and now it has been pulled out. Problem solved.

Coltsfan, I knew I had heard the story of the 140a alternators somewhere, now it is cemented into my mind ... avoid it.


So, the best course of action is to find a good core 90a Mitsubishi alternator, or a reman of reputable build (w/warranty?) like a Bosch.
Then devise a way to shield a little more heat from the alternator.
Enjoy some better cooling effect from a pair of fans being ordered and installed shortly.


Thank you for the help so far guys! /ubbthreads/images/graemlins/grin.gif
 
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G

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Stock is 90 not 85.
 

FlyingEagle

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Thank you for that.

Got a lead on some alternators (stock Mitsu).
Will see what they are when part numbers arrive in my inbox.
 

EfiniX

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Messages
647
Location
portland, or
Quoting donniekak:
Quoting EfiniX:
Whatever you buy,make sure you have a heat shield. I don't care what alternator you have, the heat coming off the down pipe will cook the regulator.



Or buy one of these and move the rectifier away from the heat.
click



+1
 

FlyingEagle

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Messages
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THE Ottawa
Okay, I've now seen the GM Saturn style alternators that have worked well for members here (ThomCasey), correct pulley style (extra rib outboard but not v-belt style like older GM stuff):

Amazon link to Saturn 96 amp

But, I am wondering if anyone has used the 1 wire self exciting (or plugged into the 2 wire setup under the plastic cap) 10SI style alternators that GM used for 40+ years.

I have found these, with lifetime warranty, from the same company that I would like to purchase fans from.

Unsure if the fitment will work or not, in the STOCK alternator location, not relocated to the rear, again I have an AC compressor. 10SI has the smaller case design.

Ebay Skip White chrome alternator 120 amp output

Anyone have experience with fitment on this style of case .... and can confirm the one wire hookup will work without a dash light?

I highly suspect that the brake warning light may come on if the stock wiring is not hooked into the field windings in some fashion.

I've read about some people using the MCR unit, coming in at 160/200 amp max if so desired:

Motor City Reman - lifetime warranty is only 1 replacement, you pay repair parts on more failures ....

The MCR units say you have to install the extra adapter to mate with the Mitsu ECU setup?


One other thing to look at is the minimum wire size to keep the system happy. Cannot fire more than the hose will flow, eh?

Quote:


System
Voltage Amps < 5 Ft 5-10 Ft 10-15 Ft 15-20 Ft 20-25 Ft 25-30 Ft
12 Volt 0-60 8 AWG 4 AWG 2 AWG 2 AWG 1 AWG 0 AWG
12 Volt 60-100 6 AWG 4 AWG1 AWG 0 AWG 0 AWG 2/0 AWG
12 Volt 100-150 4 AWG 2 AWG 0 AWG 2/0 AWG 2/0 AWG 3/0 AWG
12 Volt 150-190 4 AWG 1 AWG 2/0 AWG 3/0 AWG 4/0 AWG 4/0 AWG
12 Volt 190-250 2 AWG 0 AWG 2/0 AWG 4/0 AWG 4/0 AWG 4/0 AWG
12 Volt 250-300 0 AWG 2/0 AWG 3/0 AWG 4/0 AWG 4/0 AWG 4/0 AWG
24 Volt 0-30 14 AWG 14 AWG 10 AWG 8 AWG 8 AWG 6 AWG
24 Volt 30-50 12 AWG 10 AWG 8 AWG 6 AWG 6 AWG 4 AWG
24 Volt 50-75 10 AWG 8 AWG 6 AWG 4 AWG 4 AWG 2 AWG
24 Volt 75-100 6 AWG 6 AWG 4 AWG 4 AWG 2 AWG 1 AWG
24 Volt 100-125 4 AWG 4 AWG 4 AWG 2 AWG 2 AWG 1 AWG
24 Volt 125-150 2 AWG 2 AWG 1 AWG 1 AWG 0 AWG 0 AWG



Looks like I am limited by my 4 awg stereo wiring in places. I would have to check if my Jaguar trunk mounted battery wire is any thicker or not, but regardless, most of the rewire (alternator to fuse block, block to trunk, trunk to starter, yada yada) is all 4 AWD, if not thicker. Minimum 4 AWG.

Many things running around in my head right now, but for simplicity, a stock 90 AMP (whether or not I choose the external diode setup or not) or a Saturn alternator option in the 96A or higher range, is looking mighty tasty right now.

If my battery was not relocated, wiring would be a snap, no hassles and short enough to not be too costly. I would be looking at welding wire thickness in 20+ feet with properly prepped ends .... argh. Money signs are floating around in that case.

An external diode setup could be mounted in the driver (left) side fender well, and get enough airflow and be devoid of any heat loading from the engine bay. Hell, if the voltage and current output of the Saturn alternator are ever affected, it is still an option to keep things in check.

Those are my thoughts for tonight.
 
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MellowVR4

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Jul 25, 2009
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Milwaukee, Wi
Got a Saturn alternator on mine, got the amps bumped up on it also, car seems to respond much much better now. Also have it relocated to back of the motor.
 

G

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Feb 24, 2004
Messages
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Location
zompton
I found a few e39a bosch numbers.

90 amp reman al4008x

75 amp reman al4006x
75 amp new al4006n

140 amp new al4006ho

As well as for the 94-95 galant 2.4 ltr which uses the same plug it's:
90 amp reman al4015x

100 amp reman al4034x 98-00 montero 3.5v6 has the same plug as well.

So to answer your question i'd buy the 140 amp bosch. Both my vr4's are still on the OE units but when they finally go, that's what i'm buying.

81tm_VCf_I5_XL_SL1500.jpg


 
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turbowop

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Yakima, WA
Nice, that must be new. It wasn't available back when I got my new 75amp. Not sure I need the high output though as my current one seems fine. /ubbthreads/images/graemlins/dunno.gif
 
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