I've searched the site but couldn't find information I needed. What i need to know is how many amp alternator I should use? I have a 1971 Chevelle with a 454 a HEI distributor, wipers, twin 11" spal electric fans' Plan on adding aftermarket A/C and heat, Halogen headlights, headlight relays, maybe amp for the stereo, electric fuel pump, electronic fuel injection. I've checked the MAD electrical site and have decided to use 3 wire alternator, but don't know what amperage to use. Any suggestions?

With all you have listed, the most you can get---
More amps will not hurt anything as long as regulator is working OK.
You just need enough to supply current to accessories and maintain battery at same time.

Alternators are rated by their max output. Output follows a curve, much like engine output (horsepower and torque). Output is less at idle and slower speeds. Given what you listed, I would look at a CS130 alternator. http://www.powermastermotorsports.com/gm_late_model.html

My '70 has all you listed except the EFI and fans, and my 105A CS130 supplies enough even at idle using stock pulleys. That's with 65W H4 headlights on relays, HEI, 400W RMS amp, and electric gauges. I've been very happy with the CS130.

My '70 has all you listed except the EFI and fans, and my 105A CS130 supplies enough even at idle using stock pulleys. That's with 65W H4 headlights on relays, HEI, 400W RMS amp, and electric gauges. I've been very happy with the CS130.

I was thinking of using a 94 amp 12si but this might be a better way to go. I just have 2 questions.

1 Do you remember which vehicle your alternator fit?

2 Did you have to alter any of the factory brackets?

1 Do you remember which vehicle your alternator fit?
Late 80's trucks will work. Will need to change the pulley if using "V" belts

2 Did you have to alter any of the factory brackets? No,

http://www.novaresource.org/alternator.htm


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