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High Output Alternator Wiring Help Needed!

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Old Jul 17, 2005 | 02:58 PM
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I've managed to get the alternator into the FD. Took me about four hours of prep and fabrication, cutting the stock brackets etc...so the larger alternator would fit in. It's a 200A unit.



The FD alternator plug is a simple two wire affair, with a positive and a negative that are marked on the lip of the plug, wires are both about 14ga, one is yellow green(-), the other is yellow black (+). The aftermarket alternator has a four wire plug/pigtail with the wires marked SFLP, left to right.



S=red wire (about 12ga wire)

F=brown wire (14ga wire)

L=brown wire (14ga wire)

P=gray wire (14ga wire)



I was told by the alternator shop (Startech) to connect the S and L wires. The FD +/- wires correspond as such

S=(+)

L=(-)



Therefore I hook the red alternator wire up to the positive side of the FD's harness plug. The L/brown wire hooks up to the negative. S to positive L to negative.



I did all this, hooked up the neg battery terminal and nothing blew, no fuses went, etc..good. I start the car and she fires right up. Voltage fluctuates a bit but eventually I'm seeing around 15V on the Power FC. Car is running fine, a/c works, etc...I'm thinking all is good.



Shutting off the car, I go back to double check everything, do some final wiring, tighten bolts, etc. and I touch the alternator. It's quite hot. Hotter than any of the surrounding parts such as the brackets, UIM, and even the thermostat housing. So now I'm thinking a)she runs really hot, hence the large alternator fan or b) I've hooked up something wrong and if I let her run to long the car will spontaneously combust.



I'm most definitely electrically challenged. Any help here would be greatly appreciated!

Michel
Old Jul 17, 2005 | 03:34 PM
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I just let the car run for about 20 minutes and all appears well. Showing a solid 15V on the PFC even with the stereo pumping, a/c on, lights too...It doesn't seem to be getting unreasonably hot either but it is hot to the touch. Must be normal!
Old Jul 17, 2005 | 04:25 PM
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Silly question: Are the main & alternator pullies from the Chevy about the same size or in the same proportion as what you have now? You could really be spinning the hell out of it.
Old Jul 17, 2005 | 06:31 PM
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The alternator pulley on the new unit was sized for our cars. He's familiar with the stock FD alternator. The pulley is a hair larger than the GReddy underdrive pulley. I took her out on the road for a bit of a cruise and everything went very well. Honestly, it feels like it's pulling harder in the high mids and upper rev range. The stock alternator with the GReddy pulley put out a solid 13.5 volts constantly, except at idle with the a/c on where it dropped to about 12.2. Wondering if the higher available voltage is helping the ignition system out? Boost seemed to come on a bit sooner too.
Old Jul 18, 2005 | 01:59 PM
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[quote name='rx7tt95' date='Jul 17 2005, 04:31 PM']The alternator pulley on the new unit was sized for our cars. He's familiar with the stock FD alternator. The pulley is a hair larger than the GReddy underdrive pulley. I took her out on the road for a bit of a cruise and everything went very well. Honestly, it feels like it's pulling harder in the high mids and upper rev range. The stock alternator with the GReddy pulley put out a solid 13.5 volts constantly, except at idle with the a/c on where it dropped to about 12.2. Wondering if the higher available voltage is helping the ignition system out? Boost seemed to come on a bit sooner too.

[snapback]739198[/snapback]

[/quote]

I guess I'd wonder if the pulley for the GM applications is significantly bigger than the greddy underdrive pulley. Rephrased, you say the pulley is sized relative to the FD, but how is it relative to a GM application?



EDIT: LOL, What the guy above said ^^^
Old Jul 18, 2005 | 02:03 PM
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Also, what's that big guard in front of the fan? I've yet to see a GM alternator with the fan blocked like that.. Then again, I only ever look at/work on the SB350 or 4.3L..
Old Jul 18, 2005 | 02:31 PM
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That pulley does look a bit small in my opinion. But if its working... then great!
Old Jul 18, 2005 | 05:43 PM
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The thing in front of the fan is the fan itself! It's all one piece..sort of like the backing plate on a turbo's compressor if that makes sense. It draws air in from around the edges and funnels it into the center of the alternator. Apparently it's a very large fan (so says the guy who put it together). IMHO, it's a bit ugly and I'm wondering if I could swap it for a bling bling fan but I don't want to lessen the airflow.



Seems to be working just fine. Drove all day with it today and no issues. It seems to have "settled down" and it makes a bit over 14V at idle with the a/c on. Jumps to 15 under power/cruise.



I really don't understand how the system works...must be a loss-type system where the excess is grounded out? The cig lighter shows about 13V at idle, a/c on, with a wideband and a radar detector plugged in (dual output adapter). I'm not the first to use this alternator. Zkeller on the other forum was the first. It's much cheaper than the semi-bolt in units from Mazsport in Florida ($550) or the Stinger one (about the same). All my driveability issues seemed to have disappeared after the install. Voltage must be very critical (duh). I was really taxing the system with two pumps, stereo, wideband, other electornics, etc...not to mention the blasting a/c needed to keep me from melting. It's brutal down here this time of year. If anyone else is thinking of installing a high output unit from Startech, I can give you a walkthrough of what to do. It's fairly straightfoward if you have a few basic tools such as a grinder, grinding wheel, dremel, etc... If you take your time and do it right, it's a nice setup with very little modification, extraneous, high cost parts, or fabrication needed.
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