Upgrading headlight harness

OldnDecrepit

I have already replaced the bulbs in my 164 with high quality philips halogens but I'm looking to go a bit further.

I am contemplating replacing the headlight harness so that more power goes to the bulbs. Checking the voltages with the engine on fast idle it seems there's about a one volt drop between the battery and the headlight connector. Battery is 13.75 v, low beam is 12.75v and high beam is 12.5.

Has anyone used any of the pre-assembled relay harnesses from Ebay or Amazon?

Better to build my own?

OldnDecrepit

OldnDecrepit I have already replaced the bulbs in my 164 with high quality philips halogens but I'm looking to go a bit further. I am contemplating replacing the headlight harness so that more power goes to the bulbs. Checking the voltages with the engine on fast idle it seems there's about a one volt drop between the battery and the headlight connector. Battery is 13.75 v, low beam is 12.75v and high beam is 12.5. Has anyone used any of the pre-assembled relay harnesses from Ebay or Amazon? Better to build my own?

Try this.

PaddlerEd

Piranha in Melbourne do a superharness for Patrols and Land Cruisers that take the trigger from the original H4 connectors.

I've got the relays do the same on the Land Cruiser, so it is doable.

http://www.piranhaoffroad.com.au/product/lighting-products/headlight-super-looms

ramrod

These are more better

https://www.ebay.com.au/itm/Nightbreaker-Laser-H4-472-130-Twin-Box-Car-Headlight-Bulbs-Osram-64193NBL-HCB/291924335538?epid=25029608837&hash=item43f80bdbb2:g:ptgAAOSw4c5b2mhg

OldnDecrepit

Not if they're not getting enough volts.

Philia_Bear

OldnDecrepit;c-155952 wroteNot if they're not getting enough volts.

How many volts are being dropped?

A 40amp high quality relay and some 12g (sorry don't know metric equivilent) would solve the issue

OldnDecrepit

Wish me luck as a set of these arrived from Ebay today.

Roinik

Your biggest weakness is the flip/flop relay. We used to run a new circuit that used the flip/flop as the signal loop to a beefy relay for high beam. You could then run higher current lights. The original lights were 55/60 halogen anyway. The 164 had a 55A alternator, which is beefy enough.

VolvoHordz

OldnDecrepit;c-156231 wroteWish me luck as a set of these arrived from Ebay

Post up a eBay link if it works out. Looks like a pretty neat and easy way of doing it.

OldnDecrepit

All installed and out of sight. The only tell-tale is an additional wire to the battery, all the rest of the connector, relays and wiring is out of view. I should add that I had to run a longer wire to the battery from the fuse as the one in the kit was too short. But I was trying to hide the upgrade.

Worked a treat with full voltage to the bulbs now. Hopefully I won't melt any road signs.

Here's the Ebay link but you could make up your own using the same design.

https://www.ebay.com.au/itm/H4-Headlight-2-Headlamp-Ceramic-Relay-Wiring-Harness-Light-Bulb-Socket-Plug-Kits/401652782355?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

PaddlerEd

Are the relay holder normal ones? I've got spare (decent) relays ready for this, so I might grab one and drop it in the Land Cruiser

OldnDecrepit

I think so - here's some pictures:

I bought two so one will go in my 740.

OldnDecrepit

Finally finished installing the same headlight wiring upgrade in my 740. Of course this only applies to the H4 bulbs in the headlight unit and the fog and driving lights are unchanged.

I had to cut a slot in the headlight cover so that the wiring could go through.

Next I'll check the voltages in my 960 to see if a similar upgrade is warranted for it too.