Supplementary instruments

Thanks very much all.
I remember seeing a very detailed step by step of this subject I think by DQ, but now longer available, what happened with the ‘photobucket’ thing, I must have missed that. I like to work with an iPad as it’s much easier than going back and forth to the computer so I’m not sure I can get Chrome to work on this platform. Much thanks again for all the pics and advice.

Cheers. John
 
I relied heavily on DeQ's work in making my panel, and have some comments on the gauges themselves. I am using AFR, as Steve noted, because I am running a triple weber carburetor setup and am regularly working on my tune. You do not need this with your more modern engine management system.

I note that there is some discussion of adding a water temp gauge. In my view this provides precisely the same information as the factory gauge, displayed somewhat differently. We had a debate here on the forum about the sender BMW originally used in our cars, and I commented that it was likely the exact same sender that VDO sells today to use with its coolant temperature gauge. The sender is a simple mechanical device that allows more current to flow to ground as it heats up. The gauge, whether the stock gauges in our cars or the aftermarket gauge sold by VDO, merely displays the increased voltage on a scale that correlates the voltage flowing through the sender to engine temperature. To test my hypothesis about the similarity of the senders, I replaced my BMW sender with a new VDO "aftermarket" sender, and my stock gauge functions in precisely that same manner as before. I would not add another coolant gauge merely to have a little different display as compared to the stock gauge.

I agree that oil temp is somewhat duplicative of coolant temp, and probably overkill for a car that doesn't see the track. When I initially start my car, oil temperature actually comes up more slowly than coolant temperature, so if you prefer to warm up your fluids fully before hard driving (as I do), this helps with that.


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John - A couple of additional comments based on your questions. You do not need to run hoses; the gauges are all electrical so you are only running wires.

DeQ posted a picture of a sender that VDO makes for oil pressure that fits in the location for the stock "idiot light" sender. The VDO sender has two terminals: one to retain the stock idiot light and the other for the oil pressure gauge. DeQ also posted a picture of the oil temp gauge installed into the oil filter holder. That is exactly where I installed mine, after drilling and threading a hole in the boss on the side of the holder. I don't recall exactly where I connected my voltage gauge, but there is no sender for this you are merely tapping into the car's electrical system.
 
I agree with Ohmess, it is duplicitive to have 2 temp gauges but I went with a dial gauge for the thermostat sender as it has degrees on it and I am not sure I trust the accuracy of the original gauge even though it appears to work fine. Therefore I connected my dash temp gauge to another sender in the outlet hose fitting of the radiator, so I can see the difference in temp between the thermostat and the temp drop provided by the radiator and verify that it is functioning. Also overkill, but I had too much time on my hands that day.
 
Stevehose said:
I agree with Ohmess, it is duplicitive to have 2 temp gauges but I went with a dial gauge for the thermostat sender as it has degrees on it and I am not sure I trust the accuracy of the original gauge even though it appears to work fine. Therefore I connected my dash temp gauge to another sender in the outlet hose fitting of the radiator, so I can see the difference in temp between the thermostat and the temp drop provided by the radiator and verify that it is functioning. Also overkill, but I had too much time on my hands that day.
Click to expand...

I think that this is an excellent idea.
 
One other subtle aesthetic issue with the VDO gauges is that the outer chrome trim rings are quite large compared with the main instrument panel gauge rings. This bugged me. So to fix that I mounted the gauges from the rear of the bezel plate. The chrome rings have a step in them so that if you cut the hole a bit smaller only the inner step will show in the front. This did involve welding small threaded attachment posts to the rear of the aluminum bezel plate. For those of you with too much time on your hands ;)

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Thanks again everyone,

Couple more questions if I may.
What is the generally acceptably psi number for oil pressure? 89 m30 b35 with 160kms/100k miles
If I only went with two gauges like Sven’s great looking panel. What would be the two most useful,
I’m thinking oil pressure and voltage given the doubling up of water temperature.

John
If we can get everything covered in this tread, it may qualify for project status....
 
inovermyhead said:
What would be the two most useful, I’m thinking oil pressure and voltage
Click to expand...

I'd say the two most useful are:
- Oil pressure
- Voltage
- Air-fuel ratio (assuming you have a carbureted car)

Which reminds me of the old joke: "There are three kinds of people on this earth - those who understand mathematics and those who don't".
 
inovermyhead said:
Thanks again everyone,

Couple more questions if I may.
What is the generally acceptably psi number for oil pressure? 89 m30 b35 with 160kms/100k miles
If I only went with two gauges like Sven’s great looking panel. What would be the two most useful,
I’m thinking oil pressure and voltage given the doubling up of water temperature.

John
If we can get everything covered in this tread, it may qualify for project status....
Click to expand...

you have the answers in my threads, it is not a b35, though
 
Stevehose said:
I agree with Ohmess, it is duplicitive to have 2 temp gauges but I went with a dial gauge for the thermostat sender as it has degrees on it and I am not sure I trust the accuracy of the original gauge even though it appears to work fine. Therefore I connected my dash temp gauge to another sender in the outlet hose fitting of the radiator, so I can see the difference in temp between the thermostat and the temp drop provided by the radiator and verify that it is functioning. Also overkill, but I had too much time on my hands that day.
Click to expand...

If ever I stop tinkering with my carb tune, I plan to adopt Steve's 2nd temp gauge in place of the air/fuel gauge.
 
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