[DeTomaso] Alternator found

David D Fisher fisher95020 at yahoo.com
Wed Sep 12 15:35:34 EDT 2012


My quest for a new alternator has ended, and at the risk of sounding like a product advertisement I'll share what I ended up with. 
 
You may recal, my primary issue was the at idle with all systems running,  I was draining the battery at the rate of about 75A continous. 
 
After some searching I found a company that specs output at idle (2400 rpm at the alternator, 800 rpm at the motor) as well as ideal operating RPM.
 
I just installed it last night in 1 wire mode (although you can wire the speedo light aka 3 wire mode if you want)
 
I turned on all my consumers  (cooling fans, lights and A/C)  and it was still charging with about 50 amps to spare at 800 rpm.  Bump the RPM to 2000 and it had much more than enough current than I can consume. 
 
I cant speak to the long term peformance, especially given the pathetic air flow its going to get up there behind the engine cover but I guess it's life is still considerably better than the poor baked starter.... Speaking of which, does anyone wrap their starter to try and reduce heat soak?
 
My Alt is a Powermaster 57141, purchased from Summit.   You can get Output v.s RPM curves from the Powermaster catalague and they ship the Alt with a test tag that tells what this actual unit did on the test bench (pretty impressive, see pic)
 
No problems with fitting on the car, except the high current connector on the back was dangerously close to my valve cover so I cut about 1/4 inch off the end. 
 
http://www.poca.com/index.php/gallery/?g2_itemId=37998
 
David


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