Guide headlights low beam vs. high beam

[Kenneth H.]

This may be elementary to most of you here, but I'm trying to figure out what I have. They are two original T-3 headlights with the vertical lines in the triangle and two connection posts in the rear. I was told that they were high beams, but I can't figure out how to comfirm this. They're for my '70 LT1. I have a feeling that there's an easy answer, but I don't know what it is.

Any help would be appreciated.

Thanks.

[Joe L.]

Re: Guide headlights low beam vs. high beam

This may be elementary to most of you here, but I'm trying to figure out what I have. They are two original T-3 headlights with the vertical lines in the triangle and two connection posts in the rear. I was told that they were high beams, but I can't figure out how to comfirm this. They're for my '70 LT1. I have a feeling that there's an easy answer, but I don't know what it is.

Any help would be appreciated.

Thanks.

Ken-----


2 blade terminals = high beam

3 blade terminals = low beam

Why? Well, it's because the high beam is either on or off. The low beam sealed beams have one power configuration for when just low beams are activated and another power configuration for when high beams are activated.

[Kenneth H.]

Re: Guide headlights low beam vs. high beam

Joe, thanks for the quick response. Now I get it. So I've got my high beams and if I want to get low beams I should be looking for 3 blade T-3s. That's easy.

Thanks.

[Joe L.]

Re: Guide headlights low beam vs. high beam

Joe, thanks for the quick response. Now I get it. So I've got my high beams and if I want to get low beams I should be looking for 3 blade T-3s. That's easy.

Thanks.

Ken------


Good high beam units are easier to find than good low beam units. That's because the high beams are rarely used so the sealed beams are practically "immortal". The low beams, on the other hand, see a LOT of use. So, the low beam power configuration of the used low beam units might have burned out and, thus, have been replaced with a non-GUIDE unit at some point(s) in the past.

[Kenneth H.]

Re: Guide headlights low beam vs. high beam

Joe, I know what you mean. I just checked mine and both low beams, as well as one high beam were replaced sometime in the past with non-guide units. I guess I'l need to start looking for the guide low beam 3 blade lights.

I'm sure I'll track them down eventually. I looked for a correct date coded Holley list 4555 carb for 3 years before I found one, and it took me 2 years to find a correct date coded 1100884 alternator, so I guess they'll turn up eventually, and I'm sure I'll overpay for them.

Thanks.

[Patrick H.]

Re: Guide headlights low beam vs. high beam

Ken,

They're not that difficult to find, and if you really want there are repros of those lights.

Patrick

[D S.]

Re: Guide headlights low beam vs. high beam

I routinely find those T-3s for 1968-1971 cars at swap meets for $5-$10 each. If you see a grayish discoloration at the tops of the lamps they are either burned out or very near burned out.
Another source is old salvage yards in smaller towns.

[Kenneth H.]

Re: Guide headlights low beam vs. high beam

Patrick, Scott,

Thanks for the input. I'll keep my eyes open for them. The headlights currently installed work fine (although I rarely drive at night). I'm looking for originals for when the time comes that I get the LT1 judged.

Thanks.

[Reba W.]

Re: Guide headlights low beam vs. high beam

We just sold a box lot of both high and low beams in an auction this past weekend. My car is a 1972 or I would have bought them.