Aftermarket gauges

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Son2PopsCuda

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Hope all is well with everyone first and foremost. So I purchased a set of gauges, not to look cool so I’m hoping I can get them going. The gauges are the typical water temp, oil pressure and volts. The volts are by far the easiest, the water temp easily figured out (hope I didn’t speak too soon) but the dreaded oil pressure has me stumped, can someone please help me figure this thing out. The motor is the original 273 with original manifold and original radiator. Any help would be greatly appreciated. Thanks is advance
 
Hope all is well with everyone first and foremost. So I purchased a set of gauges, not to look cool so I’m hoping I can get them going. The gauges are the typical water temp, oil pressure and volts. The volts are by far the easiest, the water temp easily figured out (hope I didn’t speak too soon) but the dreaded oil pressure has me stumped, can someone please help me figure this thing out. The motor is the original 273 with original manifold and original radiator. Any help would be greatly appreciated. Thanks is advance
I also don’t know what this is, I had the carburetor line hooked up to for vacuum as it does idle better but I honestly don’t think it’s for that. I circled the part in the pic and the part in question is located on the backside of the manifold on the driver side very close to the distributor.

IMG_5708.jpeg
 
Circled part is a manifold vacume tap. It's not sized for power brakes so I assume it is for some part of an emissions system.

Typically the vacume advance is attached to ported vacume port on the carb.

The engine runs beter at idle because manifold vacume is high at idle and advancing the timing 10 to 15 degrees (whatever your vacume advance canister allows)

Oil pressure tap is to the passanger side of the distributer.

There should be a pressure switch in it now ( I little bigger than the water temp sender)

You can get a "T" fitting and some tubing to make a fitting that will let you tap into the oil passage and retain your oil light.
 
Circled part is a manifold vacume tap. It's not sized for power brakes so I assume it is for some part of an emissions system.

Typically the vacume advance is attached to ported vacume port on the carb.

The engine runs beter at idle because manifold vacume is high at idle and advancing the timing 10 to 15 degrees (whatever your vacume advance canister allows)

Oil pressure tap is to the passanger side of the distributer.

There should be a pressure switch in it now ( I little bigger than the water temp sender)

You can get a "T" fitting and some tubing to make a fitting that will let you tap into the oil passage and retain your oil light.
Thank you for this information, do you happen to know the thread sizes on the T fitting?
 
The vacuum port you circled was used for a performance indicator in the instrument panel. If you dont have that indicator/gauge just put a rubber/silicone cap on the port.
If you are wondering why a vacuum gauge was called a performance indicator,
vacuum gauge readings - Bing
 
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Thank you for this information, do you happen to know the thread sizes on the T fitting
No sorry. Go to the local parts store and buy / barrow an oil pressure sender. Takecthatvtonthechartmdware store and match up the threads

I'm sure it's pipe thread ( maybe 1/4 or 3/8????)
 
What does your oil pressure gage look like? What kind is it? Mechanical? Electrical with a Sender? The oil pressure port is on the top of the block near the firewall. I think it is 1/8 NPT.
 
Ported vacuum doesn’t advance the timing at idle.
Full manifold vacuum does.
 
If you can post a picture if your oil pressure gauge and the "wiring" that came with it we can help.

They come in two ways: with an electrical and mechanical. Electrical sends a signal to the gauge through a wire attached to the sending unit on top of the block beside the distributor (see pic). A mechanical gauge has a hollow plastic or copper line that runs oil from the sending unit to the gauge. Which means you will have oil pumped to the gauge inside your car! I always use a copper line in hopes it won't crack and send oil gushing into my car.

Edit: I just had a closer look at the picture I picked off FABO and it looks like this guy is running both, electrical and mechanical. You can just see the copper line at the bottom of the sending unit.

20171010_153153.jpg
 
Oh, I bought a box of ferrules so I could fix any mistakes. I also made a small loop in the tubing behind my gauge in case I had a fitting leak I could re do. It also helps with vibration but that's just me.
McMaster-Carr
 
The vacuum port you circled was used for a performance indicator in the instrument panel. If you dont have that indicator/gauge just put a rubber/silicone cap on the port.
If you are wondering why a vacuum gauge was called a performance indicator,
vacuum gauge readings - Bing
I do have the performance gauge but it was hooked up directly to the carburetor. It never did work right but I also tried this port. It has to clogged, I’ll take this fitting out and clean it up. Thanks man
 
If you can post a picture if your oil pressure gauge and the "wiring" that came with it we can help.

They come in two ways: with an electrical and mechanical. Electrical sends a signal to the gauge through a wire attached to the sending unit on top of the block beside the distributor (see pic). A mechanical gauge has a hollow plastic or copper line that runs oil from the sending unit to the gauge. Which means you will have oil pumped to the gauge inside your car! I always use a copper line in hopes it won't crack and send oil gushing into my car.

Edit: I just had a closer look at the picture I picked off FABO and it looks like this guy is running both, electrical and mechanical. You can just see the copper line at the bottom of the sending unit.

View attachment 1716102804
It’s definitely mechanical, good idea on the copper lines, I’d hate to have oil pouring into the car!!
 
I've used plastic with no issues. Copper to me is lifetime. I worry plastic will eventually get brittle. JMO
 
Plastic will get brittle with age. How its handled is a factor also. Kink it, you caused a weak spot in the wall.
 
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