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A little about Smiths gauges...

amcboy

Jedi Hopeful
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OK, a little IMHO for a minute: I really like the early TR6 gauges. I have little tolerance for the flying hershey bars of the post CF1 years. Oh, please give me actual pointers and graduations...

Flame away if you want, but its my opinion.

Now that that is out of the way, I'm here to talk about the universally crappy secondary instruments.

I've replaced all of mine.

The Oil Press. and Water Temp with 270deg. sweep Smiths mechanical gauges.

The temprature probe follows along and goes through the grommet with the tach cable.

The oil pressure gauge goes right on the existing pipe.

The Amp meter has numbers(!)

And the Fuel gauge at least matches the others (its accuracy is still debatable...)

Anyone interested in pictures?

All the gauges are available via the miracle of Ebay.

The 270s seem to light at night better than the others...

I am considering removing the dimmer knob (seriously, has anyone EVER turned these lights DOWN?) and installing a 270deg. Vacuum gauge in a matching hole.

Also considering replacing the mechanical tach with one from a Jaguar that is electronic (and matches pretty close the others visually). Maybe the matching speedo too..

I'm interested in opinions (for and against).

Fortunately the changes are relatively easy to undo should the originals be needed for some odd reason.

I'm opinionated, but influencable from outside...

Need pictures to decide? let me know.
 
Jerry, I'd rather have fully functional gauges than the correct ones that are difficult to read, if they work at all.
And, should the need arise, it's an easy job to return to originality.

My GT6 didn't even come with an oil pressure gauge! WHAT were they thinking?
Jeff
 
Jeff- for general interest:

Here's a photo of the innards of a Smith fuel gauge I took
apart and opened this afternoon. I believe the Smith temp
gauge contains the same innards.

fuel-gauge.jpg
 
Ayup the miracle of the bi-metallic strip...

Almost enough to make me install a sight glass!

Just kidding.

Most electric ancillary gauges are made this way.

Stewart Warner gauges are almost identical....

Don't even get me started on how your mechanical tach is essentially a speedometer without a odometer! Same guts!

I actually fixed a speedometer with taachometer parts! (Back in my misspent youth)
 
Tinster said:
I believe the Smith temp
gauge contains the same innards.
/bcforum/images/%%GRAEMLIN_URL%%/iagree.gif Tho I'm not certain the heater has the same resistance. Evidence would suggest that not even all Smiths temp gauges have the same heater, since the same sender that (I assume) works in a TR6 seems to make Stag temp gauges read high. There were originally several different senders that now all cross-reference to the same number ...
 
I never understood just why the numbers were dropped in favor of "C-N-H", etc. Kinda stoopid, IMO. I ~like~ knowing the thing is runnin' at 190*, charging at 13.5V, has 75lb PSI oil pressure... just how much ink did it save? Or was it decided we're too dim to need that info? "Somewhere mid-gauge" just BOTHERS me. Sorry. /bcforum/images/%%GRAEMLIN_URL%%/devilgrin.gif
 
DrEntropy said:
I never understood just why the numbers were dropped in favor of "C-N-H", etc. Kinda stoopid, IMO. I ~like~ knowing the thing is runnin' at 190*, charging at 13.5V, has 75lb PSI oil pressure... just how much ink did it save? Or was it decided we're too dim to need that info? "Somewhere mid-gauge" just BOTHERS me. Sorry. /bcforum/images/%%GRAEMLIN_URL%%/devilgrin.gif

Most likely because they got tired of owners coming in and complaining that the voltage is consistently 0.1v to low or high, or that the engine runs at 187 as opposed to 190. These gauges are fairly repeatable, but are NOT calibrated precisely. In other words as long a the needle hits the same location every day, the temp etc is matched but you can't draw any conclusion as to the precise value.

I also like knowing what is really going on, but in order to know that you need higher precision gauges than cost considerations would allow.
 
one of the first guage swaps Woody suggested for me was to swap the clock for an oil guage, a great idea i did immeditely. My gas guage was going crazy right before I put it away, correct then would show full then empty the correct... I have never been able to get the Tach to work correctly. I had Woody send me an Adjusted one but I still am not smart enough to make it work with my MSD system.
 
Got a request for pics....

Lessee how this works...

These are the "new" minor gauges:

smallgauges1.jpg


And these are the potential new tach and speedo.

newspeedo1.jpg


The tach is apart because I'm converting it from 12cyl operation to 6cyl operation....


So there you go...
 
I like the look of the minor gauges, very sharp
Methinks you'd better get the red crayon out to adjust the tach red line though!
Unless you've modified the engine.
 
Hey DScott,
I also had problems getting a tach to work with an MSD box. A Smiths electronic tach wouldn't work. I tried VDO and it read too high no matter how it was programmed and was returned defective (I don't know if they employ humans, since their tech line and email are automated and not answered). My final solution which worked marvelously in my V6 powered Spitfire was to get an Autometer 4" Cobra Tach. I took it to Autometer (though you can ship it) and they reprogrammed it for a 6-cylinder for $25 plus return shipping. I love it. It matches all the Smiths gauges and actually works! Nice clear, steady reading from a modern gauge. And their tech people actually answer the phone. They can reprogram for a 4-cylinder too (it comes programmed for a V8).

Ernie Knight
 
There is a MSD "filter" that will make the output of the 6AL or whatever work with your old electronic tach.

Methinks they are like $70...
 
amcboy said:
...

The tach is apart because I'm converting it from 12cyl operation to 6cyl operation....

Shoulda' taken the 12 cyl engine along with the tach! /bcforum/images/%%GRAEMLIN_URL%%/driving.gif
 
Perhaps a little sharing from the MB side. Early MB's had a gauge that was marked to 100 psi. Customers complained when their cars got a few miles on them and the gauge wasn't pegged anymore.

So MB marked the gauges to 60 psi(if I remember correctly) and no more customer concerns about low oil pressure as the gauges were always pegged, if the car had oil in it.
 
RonMacPherson said:
Perhaps a little sharing from the MB side. Early MB's had a gauge that was marked to 100 psi. Customers complained when their cars got a few miles on them and the gauge wasn't pegged anymore.

So MB marked the gauges to 60 psi(if I remember correctly) and no more customer concerns about low oil pressure as the gauges were always pegged, if the car had oil in it.

Clever!
 
Mazda went one step further (downright cheating if you ask me) ... on the Miata/MX5 the OP sender is a simple switch but it drives a gauge. If the OP is high enough to close the switch, the gauge reads 3/4 scale.
 
hondo402000, I expext so, but I will experiment and report...

160 though is a little optimistic.

Plus, being a Smiths gauge you'd probably have to go 225 to get it to read that!
 
Course, you could just glue it in place reading a nice 80 lbs oil pressure and never worry yourself again. Ignorance is bliss!
 
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