7M high output alternator options. Driftmotion, Suprastore or Ebay?

MarkIII4Me

Project OVERKILL!!!
Apr 10, 2005
1,249
1
38
Charleston, SC
My high output ebay alternator's bearing is noisy and only charges at 13.6 volts when hot. I've been running a 46mm overdrive pulley on it, that I'm fairly certain is what's killing it (only have maybe 2000 miles on it). Rather than going the ebay (cheapest) route, I was wondering if I'd be better off going with Driftmotion or Suprastore rebuilt 140A alternators. Are they any better build quality than what ebay offers? If so, which one will be the most reliable? Should I maybe go with a second gen Viper or MR2 alternator instead?

All I know is that my alternator's bearing is makes noise when it's cold, puts out a maximum of 13.6 volts after ran for a while, and every time my electric fans kick on at idle (once alternator is hot), my engine speed drops 1000rpm and does not recover until the fans shut off. Even after capping the IAC valve and cracking the throttle body. I also have a very large stereo that I plan on installing.

I need to do this soon, so hit my up with your opinions.
 
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MarkIII4Me

Project OVERKILL!!!
Apr 10, 2005
1,249
1
38
Charleston, SC
^
100A OE options are all I have come across which were from the 2nd gen MR2 models with power steering. If you're referring to aftermarket rebuilds, 130 and 160 amp alternators are already available for the 7M. Performance/Reliabilty seems hit or miss tho.
 

plaaya69

87T Supra
Nov 18, 2006
947
7
18
Lake County, IL
I have never once heard anything bad about the upgraded Driftmotion alternators and if I was going to replace my alternator I would go with that route as they have been around for a while and know Supras. Defiantly stay away from Ebay knock offs and no names or you will be changing that alternator again sooner that you think.

Do you have any places near you that rebuild starters or alternators? I have a few places near me and they upgrade alternators as well and come with a warranty.
 

MarkIII4Me

Project OVERKILL!!!
Apr 10, 2005
1,249
1
38
Charleston, SC
To me, it looks like the alternators sold by driftmotion and suprastore are identical to the ones on ebay. Which my research shows are hit or miss. Mechman is definitely the way to go, but they don't make one for the 7M and I don't feel like modifying the case on a $499 alternator and risk voiding its 2 year warranty. There's one place around me that rebuilds alternators, but they just reman them to oe specs and do not do upgrades anymore. I finally bit the bullet and ordered the bnr 200A Big Body alternator from their ebay store. It's extra size allows for larger windings on the stator and more surface area for cooling. It cost double what their 145A regular body alternators go for. Hopefully that make this a better quality alternator. If it can output over 150A, I'll be happy. More concerned with longevity, but only time will tell. I will report back next week when I have it installed and post my impressions of the unit.
 

Nick M

Black Rifles Matter
Sep 9, 2005
8,871
37
48
U.S.
www.ebay.com
I don't see why the engine lugging with a load from the alternator means the alternator is not working. I would also look for an upgraded unit if you have a bad bearing. Or take the alternator off and have a machine shop press in for a fee.
 

RacerXJ220

Interdimensional
Mar 30, 2005
1,504
0
0
Abalama
That's weird. I just called them, and they said they'd have to basically build it from scratch.

I could have swore they rebuild them.
 

MarkIII4Me

Project OVERKILL!!!
Apr 10, 2005
1,249
1
38
Charleston, SC
I'm in the process of installing my new 200A "Big Body" Alternator. Not sure if this is an MR2 casing or what, but it is definitely bigger than the 130A alternator that I am replacing. Weighs almost double the amount as well.




You can see just how much larger the windings are on the 200A.



We'll see if this takes care of my voltage drop issue when the engine gets hot and the efans kick on. I'm also going to run a dedicated ground from the alternator casing to the negative battery terminal. I'm wondering if this was one of my problems before since the casings are painted and the aluminum relocation brackets may not be providing a good enough contact point.
 
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