mallory unilite distributor
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Racer
Joined: Jul 2004
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From: Fredericksburg VA
mallory unilite distributor
I know next to nothing about timing and ignition system/distributors except what I've tried to learn from lars papers..but I've never actually done any tuning with this. Ive been trying to learn a little bit and was investigating my distributor. Its a mallory unilite with no vaccum advance. First question is this distributor any good or should I switch it out? and to what? But more importantly when I was looking at the distributor I noticed that the brown wire coming from the distributor, which when I looked it up online is supposed to be connected to a ground is not hooked up, its simply electrical taped next to the other wires not connected to anything. Why was this done, should I connect it, and what effect if any is it having? I didn't want to connect it and have the thing blow up in my face but I have a feeling its supposed to be connected to something at least...everytime I go into the engine bay I realize another questionable thing bubba did..need to save up the money for a full rebuild.
thanks
Steven
thanks
Steven
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Joined: Dec 1999
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From: Sierra Foothills CA
I'm not a wiring guru by any means but I did sleep at a Holiday Inn last night. 
I have a Unilite in my Z28 that's been perfect for a very long time- there were some reliability issues in the early years (25+ years ago) but at this point they are a very reliable unit. I just looked at my car & the brown wire is grounded to the coil mount on the firewall.
As for running a distributor with purely mechanical advance (mine is the same one) I've had 2 disributor experts tell me that if the advance is properly set up you don't need vacuum advance. There may be a slight loss in fuel economy but not enough to worry about. The distributor in my Vette no longer has the vacuum advance hooked up either because it was easier that way to set up a curve that would work with the big cam I'm running. That advice came from a Chevy big block expert at the best speed shop in my area and he was right. I hope this info helps.
I have a Unilite in my Z28 that's been perfect for a very long time- there were some reliability issues in the early years (25+ years ago) but at this point they are a very reliable unit. I just looked at my car & the brown wire is grounded to the coil mount on the firewall. As for running a distributor with purely mechanical advance (mine is the same one) I've had 2 disributor experts tell me that if the advance is properly set up you don't need vacuum advance. There may be a slight loss in fuel economy but not enough to worry about. The distributor in my Vette no longer has the vacuum advance hooked up either because it was easier that way to set up a curve that would work with the big cam I'm running. That advice came from a Chevy big block expert at the best speed shop in my area and he was right. I hope this info helps.
Thread Starter
Racer
Joined: Jul 2004
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From: Fredericksburg VA
Originally Posted by Les
I'm not a wiring guru by any means but I did sleep at a Holiday Inn last night. I have a Unilite in my Z28 that's been perfect for a very long time- there were some reliability issues in the early years (25+ years ago) but at this point they are a very reliable unit. I just looked at my car & the brown wire is grounded to the coil mount on the firewall.
As for running a distributor with purely mechanical advance (mine is the same one) I've had 2 disributor experts tell me that if the advance is properly set up you don't need vacuum advance. There may be a slight loss in fuel economy but not enough to worry about. The distributor in my Vette no longer has the vacuum advance hooked up either because it was easier that way to set up a curve that would work with the big cam I'm running. That advice came from a Chevy big block expert at the best speed shop in my area and he was right. I hope this info helps.
I have a Unilite in my Z28 that's been perfect for a very long time- there were some reliability issues in the early years (25+ years ago) but at this point they are a very reliable unit. I just looked at my car & the brown wire is grounded to the coil mount on the firewall. As for running a distributor with purely mechanical advance (mine is the same one) I've had 2 disributor experts tell me that if the advance is properly set up you don't need vacuum advance. There may be a slight loss in fuel economy but not enough to worry about. The distributor in my Vette no longer has the vacuum advance hooked up either because it was easier that way to set up a curve that would work with the big cam I'm running. That advice came from a Chevy big block expert at the best speed shop in my area and he was right. I hope this info helps.
you have any idea why the brown wire wouldn't be hooked up or what the effects would be? I assume I should hook it up?
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Racer
Joined: Jul 2004
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From: Fredericksburg VA
Originally Posted by SIXFOOTER
OK, a little background is in order, what year car? other motor modifications?
Thread Starter
Racer
Joined: Jul 2004
Posts: 450
Likes: 0
From: Fredericksburg VA
Mallory Unilite with no vaccum advance is all i know...i'm at school without the car right now but in two weeks i'm going back to get it i can check specific numbers then if i need to
