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Christ · 06-27-2009, 10:43 PM

The 'burg has a built in alternator, right?

It probably only produces about 10-20 amps, max.

For posterity, the one on my tractor's engine is built in (it's part of the flywheel). It takes about .6 HP to make 15 amps @ 12VDC. (According to Briggs, IIRC)

15*12 = 180 watts

Assuming 50% efficiency, 180 watts takes about .5 HP to make, the rest of the power loss is heat, I presume.

If your 'Burg makes 50 HP max (unlikely, probably closer to 30), you're looking at 1-2% of your total output being used for max load on the alternator. Relatively insignificant, but you may get something from it.

06-27-2009, 10:43 PM	#4 (permalink)
Christ Moderate your Moderation. Join Date: Nov 2008 Location: Troy, Pa. Posts: 8,919 Pasta - '96 Volkswagen Passat TDi 90 day: 45.22 mpg (US) Thanks: 1,369 Thanked 430 Times in 353 Posts	The 'burg has a built in alternator, right? It probably only produces about 10-20 amps, max. For posterity, the one on my tractor's engine is built in (it's part of the flywheel). It takes about .6 HP to make 15 amps @ 12VDC. (According to Briggs, IIRC) 15*12 = 180 watts Assuming 50% efficiency, 180 watts takes about .5 HP to make, the rest of the power loss is heat, I presume. If your 'Burg makes 50 HP max (unlikely, probably closer to 30), you're looking at 1-2% of your total output being used for max load on the alternator. Relatively insignificant, but you may get something from it. __________________ "¿ʞɐǝɹɟ ɐ ǝɹ,noʎ uǝɥʍ 'ʇı ʇ,usı 'ʎlǝuol s,ʇı"