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Sweet72 · 09-08-2004, 06:08 PM

I agree with Longhorn Man 100% on this one. Your dim lights and oscillating ammeter are not a result of the HEI drawing more current from your 62a alt., but the RPM at which your alternator is turning. I believe a higher amp alt. will cure the problem (90-140amp) given the higher current demand of your stereo system etc. The stock alt. on my '72 GMC was 42a leaving much to be desired with all the lights on and signals/brake lights on. Internally regulated alternators are just faster to catch up with the demand being solid state as opposed to the old electro-mechanical ext. regulated set-ups.

09-08-2004, 06:08 PM	#5
Sweet72 Registered User Join Date: Nov 2003 Location: Alexandria, VA Posts: 1,534	I agree with Longhorn Man 100% on this one. Your dim lights and oscillating ammeter are not a result of the HEI drawing more current from your 62a alt., but the RPM at which your alternator is turning. I believe a higher amp alt. will cure the problem (90-140amp) given the higher current demand of your stereo system etc. The stock alt. on my '72 GMC was 42a leaving much to be desired with all the lights on and signals/brake lights on. Internally regulated alternators are just faster to catch up with the demand being solid state as opposed to the old electro-mechanical ext. regulated set-ups. __________________ '72 GMC SWB C1500 Custom, frame-off in progress. 383 SBC, 9:1CR, Comp Cams XE262H, Scat internal balanced crank, Eagle SIR 6" rods, Keith Black dish pistons, Dart Iron Eagle 72/180 heads, Weiand Stealth intake, Stewart stage I water pump, Holley 4bbl vac sec, TH350 with B&M Shift Improver Kit. 12 bolt positraction.