DIY: Headlights Upgrade with Dual H1, H7 Bulbs

Thread Starter #1
Jul 29, 2013
Hoshiarpur, punjab
hi guys! i am going to share very important DIY for headlights upgrade for my Chevy OPTRA. you can try with similar headlight setup cars.
This car has separate bulbs for Low and High beams. low beam bulbs are H7 and high beam bulbs are H1, 55w each. This stock setup doesn't give confidence while driving at night on roads without street lights. That's why i am upgrading with higher wattage bulbs.
Now option is to replace stock bulbs with higher wattage 80 or 100w bulbs with wiring harness ( thicker wires + relay + fuses).
Bulbs are available in the market , i chose Philips 80w H7 (low beam) and 100w H1 (high beam).
Now there is a problem. H1 H7 wiring harness not available in the market or online (at least not in my town). H4 wiring kits are easily available locally. purchased Minda H4 wiring harness for Rs. 510 . Some connector pins for rs. 10.
I am going to modify h4 wiring kit to convert it to h1 h7 bulbs and stock headlights wiring too need some modification.
starting with removing both headlight Assemblys. After removing dust cover you can easily replace all four bulbs with new ones.
Now problem number 2. These headlight assemblies have internal wiring for high, low beam bulbs, parking lights and leveling motor. You should raplace high and low beam wires with thicker wires to avoid melting due to higher wattage heat. You can drill holes in dust covers to route wires into assembly. but if you want to go my way , you have to modify the stock connectors replacing stock wires with thicker wires.
Luckily in my case stock wires inside assembly were thicker already, so saved some time. Now need to modify stock connectors.
Now carefully find the three wires in the connectors , high , low beams and one common(ground). note down the location of each wire in connector. now pull these three wires out of connector. for H4 wiring connectors , i am posting a picture to find wires for low and high beams.
connect the stock pins to your new wiring kit low, high and ground wires and insert back into stock connector. make ground connections to suitable place on car body. attach new wiring harness input to your stock wires high, low and ground . I am using connector pins for this. cover all joints with good quality electrical tape. route the new harness in the engine bay to the both headlights properly. wires should not touch hot or moving parts in the engine bay. Use zip ties to securely hold the wiring on it's place. mount relay with fuses on a secure place. Attach the connectors to headlight assemblies and install the assemblies back to your car.
Now after all the thing fixed properly, connect the final connector of red thick wire of your new harness kit to the +ve side of your car battery.
park your car on flat surface facing toward a wall. Start your car and turn the headlights on. Check Low and High beams. Level the headlight if needed using Screws provided on the back of headlight Assembly. Enjoy [cheers]
Note: Now you have very powerful headlights. please use high beam responsibly where required. Switch to low beam to avoid blinding oncoming traffic. Drive safe. [;)]









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