Re: 26th Series 12v Conversion Thread

Posted by Hans Ahlness On 2015/12/27 23:21:32

I converted my car also, and here is some info for a 24-25th series car. These are the applicable 12v bulbs:

Instrument lights - 57
Turn signal/hi beam indicator lights - 53
Oil/battery indicator lights - 57
Column shift indicator light, ultramatic - 53
Inside glovebox light - 57
Under dash courtesy lights - 90
Rear dome light - 104
Headlights - H6024 halogen (use relays)
Front park/turn sig lights - 1157A (amber)
Tail/brake lights - 1034 (also could use 1157, 2057, 198)
Reverse lights - 1156 (also 199, 1141)
Rear license light - 67
Trunk light - 89

I had to replace some other components also, using these allows the use of the existing points etc in the distributor:
Coil - NAPA IC12
Ignition ballast - NAPA ICR13

Because I used an aftermarket wiring harness with a fuse box and new horn and turn signal relays, I could also discard the circuit breakers behind the instrument panel and wire components to dedicated fuses.

I also purchased a prewired headlight relay setup from the same vendor, to allow modern halogen headlights while retaining the original headlight switch.

I procured a set of horns and a heater fan from a wrecked '55 which were already 12v.

I did not replace the instrument voltage converter (powers the gas and temp gauges) as the existing unit will work with 12v, it provides an intermittent 5v signal to the gauges.

I didn't replace or convert the starter, although there have been some reports of problems from that so far no issues in 900 miles. But you'll need to replace the starter solenoid switch with a 12v three-terminal unit.

I replaced my generator with a rebuilt Delco 10SI alternator, I used a NAPA p/n 213-4011B reman unit, about 63 amps. Overkill but no cost advantage for going smaller. I got a 3-wire unit, which allows me to wire the BAT idiot light into the alternator wiring - so if the BAT light comes on either the alternator has quit or the belt came off.

There are some other installation details in my project blog, but these are the parts to change.