Are you talking about your head light relays? If so, a larger diode to trigger the second relay isn't buying you anything. All you need is enough current to make the relay coil energize and that's it.
yes thanks Mr. big John, but the reverse of this i am worried about the current going the other way and using hoover dam to only stop a piss stream as an example.
I've got a real good solution to all this.... don't drive at night and if you do make like it's 1967. That's what I do.
If it ain't broke don't fix it. Your still running the same amps regardless to the bulbs. Just pushing it thru a different way. You may be making it easier on the switch and dimmer, but in the end the head lights are still using the same power....
allright. even though that argument is not even rational to me, let me present this for consideration. and i again state everyone should upgrade their headlight wiring per slantsix dan guidelines, regardless if you have current problems or not. buy his and/or crackedbacks stuff if you dont feel good about wiring.
exhibit A
exhibit B
this is typical 50 year old wiring, as found in our cars, as found on the 68 fury i bought from pacific NW. notice the wire melt in pic #1 wavy wire, and the exposed wire / broken insulation in pic #2.
A MELTED WIRE. YOUR CAR. THINK.
In addition, the wire is 18 AWG stock, which is minimally capable for the amount of power our headlights can use (dont take my word for it see wire melt in stock wiring in pic above).
Its 50 years old, shows breaks (see pic #2) in insulation. thats enough to reject it right there.
As you said, in the stock configuration ALL HEADLIGHT POWER runs thru the light switch at the dash. so if you have 4 stack lamps like a 68 fury you could push close to 20A thru your dashboard thru this switch.
same with the foot dimmer switch as you mentioned. all this power flows thru it. And the ammeter circuit. and your bulkhead - 4 times !
In the stock configuration, the entire front light system is grounded by 1 ring terminal up in the front right that all the grounds feed to - 50yrs old and as skinny and brittle as the rest of these wires.
By doing the crackedback harness and employing relays per slant six dans guidelines:
we increase wire AWG from 18 to 14, which is proper AWG spec for this length of wire run at this amperage
we entirely remove the headlamp power from traveling thru the inside of the car at all- no dash, no ampgauge, no headlight switch, no foot dimmer. we just removed ~20A from that entire harness that was already inadequate at best.
we have added a level of redundancy by employing 2 power feeds and 2 relays driving hi / lo separately.
we have added less potential draw on the battery by using the ALT stud as power source.
new headlamp sockets v. 50 year old ones.
new wire v. 50 yr old wire.
potentially better connectors and connections than 50 yrs ago - especially if its handmade 1 wire at a time by a guy sitting here watching an internet car forum.
ive actually been chatting with the professor about this, and have maybe come to running 3 relays total: 1 for low beam lo side, 1 for hi beam lamps, 1 for low beam hi side. i dunno yet im still kicking it around in my head.
but to me the pro so many far outweighs the con. and a melted wire man. thats gotta go.
