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DISCUSSION => Electrical => Topic started by: fruit_bearer on June 06, 2008, 07:19:02 PM

Title: Upgrade to H1/H4 bulbs
Post by: fruit_bearer on June 06, 2008, 07:19:02 PM

my headlights just don't give off enough light for me to feel comfortable driving at night, so i'm looking to upgrade to H1/H4 bulbs.  what wattage bulbs do i need?  also, do i have to make any modifications to the wiring for these bulbs to work?  someone mentioned something about replacing fuses - which ones need to be changed?  

thanks!

Title: Upgrade to H1/H4 bulbs
Post by: Wise Old Dog on June 06, 2008, 09:12:13 PM

The ones that blow, LOL

Title: Upgrade to H1/H4 bulbs
Post by: twinpop171 on June 06, 2008, 10:29:29 PM

http://www.m42club.com/forums/showthread.php?t=4611

Title: Upgrade to H1/H4 bulbs
Post by: nomad on June 07, 2008, 08:33:59 AM

Anyone know of a way to change the wiring to accommodate the dual filament bulbs so that the high beam comes out of the same light as the low beam? This would be a good alternative to use when replacing the high beams with intake scoops.

There should be a way to splice the wiring together to work with the right +/- but I'm not sure about relays etc.

Title: Upgrade to H1/H4 bulbs
Post by: ak96ss on June 07, 2008, 06:53:12 PM

To answer the OP, the connectors for the H1/H4 combo are different than the sealed beam bulbs, presuming that is what you have. As far as changing fuses, I was and remain leery of just changing fuses out without considering the fact that the fuses are sized for the wire that is on their circuit - in other words, a 7.5A fuse is used because the wire won't support much more than 7.5A. If you pull your 7.5A headlight fuses and just slap 15A fuses in to replace them, you run the risk of a lovely fire. It might not happen, but you've just increased the chances that it will.

I ran separate looms and relays, using the original wiring to turn on the relay, and 12ga wire to support the higher wattage bulbs for my H1/H4 lights.

(http://lh5.ggpht.com/2006TopBanana/SEsef8i2r2I/AAAAAAAADdM/tHB9AQR7fIc/s800/Headlamp%20Wiring.jpg)

Title: Upgrade to H1/H4 bulbs
Post by: Wise Old Dog on June 08, 2008, 01:23:35 PM

10 amp is all I needed for the fuse upgrade, and the additional load is only on when your high beams are on. I was leary about the wire size as well, so I checked them for heat and found no problems. But I am using standard wattage bulbs. If you go to a higher wattage, then yes you need relays and bigger wire.