Is my Alternator OK (enough)

[bobm]

Looking for some assistance from the collective. 1966 911 304014 all original (rebuilt to 2.2) motor and electrics. Been running fine. I have added 128 fog lights from Auto Foreign (Eric) No issues. I have now added (last 30 days) Eric's thru grill lights. I love the look. Driving with all lights on I started having a high speed miss. Stopped for gas fill up. Car would not start. Pushed started (not cool with wife in Car). Once home I charged the battery. Once charged checked with multi-meter 12.5V. at battery. Started Car 12.5V brought to 3000rpm 12.5V ( at battery). I went thru normal routine, checked all battery posts, wiring, grounds. Cleaned all no change. I took the regulator from my 1970 914-6. I now get 14+- at Battery. Regulator issue? I took the original regulator apart and cleaned points and connectors. Once reinstalled I see the points close at 1800-2000 rpm. I now get 14+- V at battery. I see the headlights get a little brighter when I rev up the motor ( red light on at idle out at 1500+). The high RPM miss is pretty much gone now. Not sure if the issue has been corrected.
I think the original Alternator is 35A (please correct if I am wrong). Will this Alternator keep up with the AMP draw of my new light set up. When all on I have 2 headlights, 2 fog lights and 2 driving lights (all Halogen). Should I look for a higher AMP Alternator. Should I switch bulbs to LED's. I have not installed any relays to the system (Not sure How). Don't want to get stranded again. Thanks for any assistance

[edmayo]

Without doing the math on the total draw for all the accessories and ignition , I'd say you're close to the max alt. outout equaling draw. But it sounds like you were operating at a loss before, which you've now fixed. Put an ammeter in series with the battery and turn on all accessories, add 5 amps or so for ignition (because engine is not running) and you should be able to determine whether your 35 amp alt. is enough.

[304065]

Good job diagnosing the defective voltage regulator. I use a solid state one for driving and the original for show.

Yes the original alternator is only 35A, on a sunny day when it was new. That's only 490W. Figure 55-60W for each headlamp, 35W each for the 128s and probably 55W each for Eric's TTG 118s. That's 300 watts right there, without taking into consideration the voltage drop, high-resistance connections and the like.

Your main issue was the bad VR but you may want to consider going to a 55A Bosch Alternator from the '69.

[bobm]

Thanks for the info.
I would like to keep the external regulator. Is the 69 50 amp a direct fit. I understand that some you have to have the ring machined.
Any thoughts on changing to LED bulbs?? Would relay's help with switch life?
Thanks again
Bob

[tom1394racing]

The later, 55 amp alternator is a direct fit in your fan ring. No machining needed.

[304065]

But you may need to modify the wiring harness. . . I bought mine from a nice gent up in Connecticut with a mustache and a huge collection of Porsche parts