View Single Post
Old 09-08-2018, 02:53 PM   #5 (permalink)
Master EcoModder
Stubby79's Avatar
Join Date: Sep 2012
Location: Victoria, BC
Posts: 1,266

Firefly EV - '98 Pontiac Firefly EV
90 day: 107.65 mpg (US)

Little Boy Blue - '05 Toyota Echo
90 day: 33.35 mpg (US)

BlueZ - '19 Nissan 370Z Sport
90 day: 17.19 mpg (US)
Thanks: 42
Thanked 365 Times in 275 Posts
if they're thinner, and the coil appears to be the same size, then it has more windings and therefore will put out higher voltage but less current.

Chances are the old coil will put out 12v at higher RPM, but there's a limit to how much current it can put out, so as long as the load is high enough, the voltage never gets up that high.

Unregulated systems use the battery and the lights to limit the voltage. Light burns out, battery tends to get over charged and dies prematurely. Battery goes out, lights get too much voltage and blow the bulbs. Half the reason motorcycles, old ones at least, always have the lights running.

I'd slap that new coil on, and throw on a cheap little regulator. If the voltage never gets high enough (above 14v, give or take), the regulator won't ever kick in. But if you don't have enough load on it, it will save your bulbs. A volt meter/multimeter will tell you if you're making roughly the right voltage or not, or if your new bulbs are putting too much of a load on it and you need to use smaller (or bigger) wattage bulbs.
  Reply With Quote