Watts = Amps X Volts
If you have a 17 amp alternator - you have 204 watts to play with at optimum output
100 for the headlight - 48 for the signals - another 24 to 48 for the ignition
The 204 watts is at maximum, so most of the time you will be lower and pulling from the battery. Once the voltage starts dropping below about 9 or 10 volts you get the missing. Try a standard headlight bulb (55/65 watts) if it works you found your problem (cheap fix). If this solves your problem but want more light the HEI headlight is an option. They only pull about 35 watts, but at a bit price tag.

 

Not sure where you're getting your math formula from, but a 100 watt load on a 12 volt system draws 8.33 amps, not 16+ amps. Formula for power in a DC system is P=VI, where P is power, V is volts, and I is current. Therefore, I=P/V. Where did that quote (with the x 2 factor) in your first post come from?

 

OH good thanks for the corrections.
I can't find the web site now that I got that formula? but I'll take your word for it..
I have changed the bulb to the 65/55 and removing the bulbs in the front signals now the system will charge but I haven't taken it for a test ride yet.
Thanks again this has been a real puzzler for me!

 

here's the page with the formula
I'm guessing I misunderstood and the X 2 was because of two bulbs as in an auto.

 

Thought that might be what the mix-up was!

I remember a guy who modified his genny Shovel to run a car alternator & regulator. He engineered a belt pulley off the generator drive gear, welded tabs on the frame tubes, and mounted the alternator on the tabs. Plenty of power and ultimate reliability! It looked oogly, but as he said, "From where I sit, I can't see it!"

 

The last year or two that they built servi-cars they came with a factory set up like that. By then they were electric start and had all that police equipment, lights, radios and siren they needed all the power they could get.

 

Yep I've seen that ugly setup before too Akk!
I'm still kicking myself for giving away the fan cooled police generator that was on my 68 when I got her but it was toasted and I tried a couple times to have it rebuilt with no success.
Wish someone would build an alternator that would be larger capacity and look like oem generator.

 

Update...
seems to be fixed after a test ride yesterday.
I installed the smaller watt head lamp bulb and replaced the front signal lights with LED's and installed a volt gauge to keep a better eye on whats going on with the charging system. The alternator conversion is keeping the battery up to 13.5 volts while running.
Thanks for the help

 

Rodney, I am running the 'stock' gen on the pan. NOW, I don't have blinks, etc, but do have electronic ign (Mallory)
If you want more light, I run the PIAA Extreme White 110/100w. Pulls 60/55w. I was running quartz halogen tail/brake light, but changed over to LED for brightness.
Been runnin' this for years and years, no probs, other than the boiled batt syndrome from the oil tank.

 

Thanks for the head lamp note, I really don't want to spend the $$ on the HID system.
I'll see if I can find the PIAA bulb.
am also looking to find the GOOD LED 1157 for the tail stop light.