1 Headlight Relay vs 2
Thread Starter
Intermediate
Joined: Jul 2008
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From: Raleigh NC
1 Headlight Relay vs 2
I noticed in some of the vacuum diagrams that the 69 model uses 1 relay and later C3's use 2.
I would think GM did this for some reason or another. Anyone have a thought on this?
I am restoring 2 car right now, not C3's but they utilize the same vacuum systems as a C3. One of my cars has a single relay the other uses 2.
Since I am replacing or R&R the entire systems. I was wondering if I should convert them both to a 1 relay system or 2 relay system.
Thanks
1st post
I would think GM did this for some reason or another. Anyone have a thought on this?
I am restoring 2 car right now, not C3's but they utilize the same vacuum systems as a C3. One of my cars has a single relay the other uses 2.
Since I am replacing or R&R the entire systems. I was wondering if I should convert them both to a 1 relay system or 2 relay system.
Thanks
1st post
Safety Car
Joined: Sep 2005
Posts: 4,226
Likes: 643
From: Orange County Ca
I have a 69 with 1 relay and it works fine. But, I'm thinking that the general wouldn't spend a extra cent if he didn't think it wasn't better. Now if they went from 2 to 1, that would be a different story.
Drifting
Joined: Apr 2007
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From: Cameron Park CA
Cheers,
Pete
Safety Car
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From: Austin Texas
Corvette of the Year Winner 2017
2016 C3 of Year Finalist
69 = 1 wiper relay, it is plumbed to a T going to both R&L light Assys.
I would think 1 relay may be a bit slow opening the headlights,
but ...1 relay would also open both at the same time.
I would think having 2 relays, could more easily,
give you the lazy Eye Opening.
69VETT
I would think 1 relay may be a bit slow opening the headlights,
but ...1 relay would also open both at the same time.
I would think having 2 relays, could more easily,
give you the lazy Eye Opening.
69VETT
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
My '77 had two factory relays. I removed one, split the lines, and now run one relay for both headlights. Maybe it was my system, but now the lights go up and go down a bit more uniform.
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From: Dayton, Ohio
Thread Starter
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From: Raleigh NC
Thanks for all the input!!
Drifting
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From: Cameron Park CA
Cheers,
Pete
Team Owner
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From: Orange Park Florida
I noticed in some of the vacuum diagrams that the 69 model uses 1 relay and later C3's use 2.
I would think GM did this for some reason or another. Anyone have a thought on this?
I am restoring 2 car right now, not C3's but they utilize the same vacuum systems as a C3. One of my cars has a single relay the other uses 2.
Since I am replacing or R&R the entire systems. I was wondering if I should convert them both to a 1 relay system or 2 relay system.
Thanks
1st post
I would think GM did this for some reason or another. Anyone have a thought on this?
I am restoring 2 car right now, not C3's but they utilize the same vacuum systems as a C3. One of my cars has a single relay the other uses 2.
Since I am replacing or R&R the entire systems. I was wondering if I should convert them both to a 1 relay system or 2 relay system.
Thanks
1st post
curious what you working on there.....I"m an olde tyme Pontiac man from WAY back.....
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Intermediate
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From: Raleigh NC
It's a 1975 Canadian made car called a Bricklin
I have some pics in my profile link
Last edited by jetnoise; Jul 12, 2008 at 09:56 PM.
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From: Dayton, Ohio
All you do is restrict the vacuum to the fastest headlight.I use aquarium filter bubble rods,they are about an inch long and 5/16 diameter.I just put them inside the hose which will slow down the vacuum going to the actuator on the headlight.
Melting Slicks
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St. Jude Donor '08
Thread Starter
Intermediate
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From: Raleigh NC
Thread Starter
Intermediate
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From: Raleigh NC
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From: Dayton, Ohio
Pro
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Would the length of hose from relay to actuator make any difference in opening speed ?
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I think it depends on how tight the actuator is and what kind of shape the mechanism is in.Changing the length "should" but I have tried doubling the length of the hose and couldnt see much difference thats why I went to restricting to change the speed.
