H4 wiring harness upgrade

[dahondr98]

Oh damn that's annoying. So how much did it cost you for all those parts? And is there any kits that have what you mentioned for sale as a package?

Yes, there are. Contrary to what Vinny said, they are easy to get hold of (sorry Vinny!). The two main looms available in Australia are made by Piranha and ARB, who both supply parts for 4WD's. I've got the Piranha kit in my Civic, and it makes quite a difference. I did just get a price list from ARB recently (I'm a shareholder, so was checking their products!), and their wiring loom costs about $150 - I can't confirm the exact cost, as I suffered a PC crash soon after they sent me their price list, and I lost it when re-formatting my hard drive. The Piranha kit uses 6mm wire, which apparently is slightly thicker than the ARB loom, and I think they cost about $200.

The ARB looms are available at any ARB 4WD store, and the Piranha loom is available from plenty of 4WD accessories stores, such as TJM, Opposite Lock, 4WD Warehouse, etc. Either will be better than the thin wiring Honda uses as standard. Another seller of upgrade looms on Ebay is Hobzee's 4H 4WD Shop - see http://cgi.ebay.com.au/Nissan-Patrol...item33565dc2ed , or at http://www.4h.com.au/prod358.htm . As he says on Ebay, although it's advertised for the Nissan Patrol, it will fit most other cars - he uses 6mm wire for high beam and 4mm wire for low beam - Honda use inadequate 2.5mm wire. I did see recently on a 4WD forum that there is a 4WD shop in Melbourne that has identical Landcruisers, with the only difference being a Piranha loom, and apparently the difference in light output between them can be seen easily - apparently most people spend the money to buy the loom when they see the difference! Most Jap cars use the same thin wire, whch is why Nissans and Toyotas also benefit, like Hondas.

From tests I did when my Civic was new, the voltage drop was about 15% at the headlights (more than 2V drop), and according to Hella, that equates to the headlights only being 54% as bright as when they have full battery voltage. I can certainly confirm, from swapping the plugs between the aftermarket Piranha loom, and the original loom, that the aftermarket loom gives much brighter light, on both low and high beam.

If you want to build one yourself, you can get all the parts from NA Auto, who supply auto electrical parts online - see http://www.naauto.biz . Unfortunately they have had someone redesign their online shop using Javascript, so it takes a long time to load, and doesn't work unless you enable Javascript. Get rid of it, NAAuto! You can certainly save some money by doing it yourself, but it is a bit of work.

Finally, if the EG headlights have plastic lenses, don't use higher wattage globes - you'll wreck the lights very quickly. If they are glass lights, then you can use higher rated globes (eg 80/100W), but you need to upgrade the wiring to handle the current. Better to do that first - most likely you won't bother changing the globes - the Philips globes are the best available at present in standard wattage.