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BobbyK · 03-17-2003, 08:53 PM

Most of the time the problem with dull factory headlights is the wireing.With 30 year old wireing you can end up with significant voltage drop by the time the power reaches the lights.

If you have a voltmeter measure the volts on the back of the alt.Then measure the volts at the light with the light on.If you have less than 12 volts at the light your headlights will be dull and not perform well.

If you upgrade to a higher wattage bulb(H4,xeon,etc) the performance could be even worse than the orig. headlights.

A simple upgrade to a pair of relays will get a full 12-14 volts to the headlights and the difference in the performance of your lights will be amazing!

It can be wired like this.

03-17-2003, 08:53 PM	#22
BobbyK Registered User Join Date: May 2000 Location: Petrolia,Ontario,Canada but working in Port Huron,Mi. Posts: 1,772	Most of the time the problem with dull factory headlights is the wireing.With 30 year old wireing you can end up with significant voltage drop by the time the power reaches the lights. If you have a voltmeter measure the volts on the back of the alt.Then measure the volts at the light with the light on.If you have less than 12 volts at the light your headlights will be dull and not perform well. If you upgrade to a higher wattage bulb(H4,xeon,etc) the performance could be even worse than the orig. headlights. A simple upgrade to a pair of relays will get a full 12-14 volts to the headlights and the difference in the performance of your lights will be amazing! It can be wired like this. __________________ 71 blazer,350SBC,approx.375HP,700R4,factory GM TPI.Dual electric fans,33x12.5x15 ATR on stock suspension. Petrolia,Ontario,Canada but working in Port Huron,MI. See ALL my Blazer pic's HERE