I’m working on a 356 C that has been converted to 12 Volts. I bought the tach, and the oil-temp gauge.
With the oil- temp gauge came a small white box with 4 or 5 wires coming out of it. I don’t have it in front
of me, so I can’t be more specific. According to Sierra Madre, I need this box to get the gauges to work.
I didn’t get a schematic, and can’t seem to figure it out. Can any body help?
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Is this the ( VDO ?) 356 replica gauges that use GPS ? I've installed many 356 gauges ( replicas) and haven't seen this box you mention
This is diagram they have on their site - I only see the GPS Antenna
I saw these gauges on their site as well. They say call them for technical assistance and thought this sounds good if they support the buyer's questions.
SMC buys these gauges from me. Usually they forward technical questions to me, as their team is more sales based. Shoot me a PM or drop me an e-mail and I can help.
FYI, there is no box for the combo gauge, the little white box is a GPS sender for the speedo. Red to 12v constant power, white to speedo male terminal labeled "w" and both black and green to ground. Once wired you'll need to sit with a clear view to the sky, key on, for a few minutes for the unit to acquire it's multi-satellite signals. Once you do this once you usually don't have to do it again (unless trailered to as new location or battery diosconnected/dead), but it must be sitting still to do it the first time, it will not find signal while in motion the first time.
Sierra Madre seemed to have pumped up their price for the 3 gauges and oil sender & Speedo GPS to $1016! Ouch. Seems price used to be like $650. Argh - and then they send you to SE for tech support.
Wonder if the gauges are made out of the US. If so, the increase in cost most likely the added tariff. Doesn't look like inflation has direct impact. The difference is way too much.
Still cheaper to go to Beck - the source:
Gauges (3) on ebay $629
Senders (s) on ebay $200
Total $829
That’s the answer on the white box. I couldn’t seem to get that though to
Sierra’s sales people, after trying At least 5 times. I’m still using the old cable
drive speedo, so I don’t need the box. They argued it was necessary for the
other gauges. I now have the schematic, which I couldn’t seem to get from them.
I’m sending pictures of the other parts they sent me. Can you please let me
know It their right?
So those are the gas gauge sending unit for gas tank - I'm familiar with the one in VW tank and it looks same (ohms could be different). Will it fit a Porsche 356 tank? - yes if same diameter opening & bolt pattern. The other is the oil temp sender which would be matched to the temp gauge so use it over what's on 356 engine now.
The tank float is the same. The oil temp sender is wrong. I think it fits a 911.
Since you didn't buy the Speedo - I think I'd tell them you were mis-sold the sender package and want to return it to get your $200 back. If the current oil temp sender doesn't work with new gauge (voltage shouldn't matter) ask Carey to supply one or get spec from him. Like you said you don't need the GPS sender. Assume the box is for the temp sender - it's a Porsche 914 part # - but the part picture is not a 914 oil temp sender. You are probably right its - for a 911 --- see if it has a 901 or 911#. stamped on it.
My Speedster came with a set of gauges, referred to by some, as cheap Chinese cr--. I took delivery 14 years ago, the gauges have been trouble free, knock wood.
My Coupe came with VDO digitals. After a couple of months, the sensor connected to the left front wheel, quit. I replaced the sensor, the speedo quit clocking cumulative odometer mileage. I replaced the speedo, odometer did not work on the replacement.
I found a set of the Chinese cr-- gauges on eBay. Installed them, no problems for the past 3 years, knock wood.
Being one of the champions of unintended consequences, I failed to consider the Chinese gauges have slightly larger diameters than the VDOs. One grinding template, 3 vacuum cleaners to control the damn dust, and itching for weeks, I installed the gauges.
Well that is one way to keep the mileage low on the car... just kidding.
Actually, while not period correct the 914 guages are real instruments, with good lighting IMO. The chinese ones are not very bright at all and while you can increase the wattage of the bulbs I am not sure the silk screening would not disappear with more light. : >
IAM-RAY: I had to laff at your post I wish I could say the low mileage thought never entered my mind. Respect for the Karma gods, keeps me straight.
I'm not sure who in China made the gauges I have, but they were bright, I did not change the bulbs. They're not as bright as 914s, a friend had a 914, you could read by the light of those things.
To me "period correct" applies to original equipment and replicas. I lean toward Jay Leno's replica definition. To fit that definition my cars would have to be built exactly like the originals and use parts interchangeable with the originals like a Pursang Bugatti or like some of the new Sharps style rifles.
As a person with more years in the review mirror than through the windshield, I'm trying to have fun not fit in. The fact that you have one of these fancy little clown cars, I suspect you're not trying to fit in either. Good on you!
Sorry to punish you with all this verbiage. I know, shut up and move on!
So Beck's new gauges are such an improvement over the old replica gauges. Imagine being able to compensate easily for different size/profile tires and actually have a correct reading! And no rubbing cable to the right left hub. A trip odo you can reset without coming to a complete stop.
Wolfgang they can be calibrated as easily as driving a ONE Mile distance and hitting the button. Also if you use your GPS on your phone or anything more precise you can see how fast you go and tweak the guage by clicking + or - on the set up screen ... pretty cool.
Ewatub, I guess were both chuckling at each others posts, I try to take the postings in good humour. 
Yeah, banish that thought of being disingenuous
BTW I don't have a sensor on my front wheel maybe that was the issue with your set up. Not sure.
My first IM was as close to original with all the fake labelling... My second IM is made to fit my body style, different seats, full subie. etc
I like it a lot and I usually say it's an IM not a P car... of course most people force you into the 356 discussion at some point. Like most of us you can't get anything done is your going somewhere and keep talking at the pump...
The gauges were built for a 221-012 VDO sending unit, Ohms range 73-10 We've had some that seemed to like a 60-65 Ohms max better, but that is just an adjustment of the float stop and easy to do.
Since the oil temp (or coolant temp) scale is un-numbered, you can use a variety of senders for it and it just changes the relative position the needle. A 120c sender is 3/4 at 190F degrees, while a 150c sender is closer to 1/2 way at 190F degrees. The resistance of these senders seems to be the same regardless of thread pitch/size, so in that case just find the one that works for you, or buy an adapter fitting to make the one you have work. You can find adapters for these senders many places, like Summit Racing or at my shop or just Google it.
BTW the Ohms range and 221-012 part number reference above is for the fuel sender.
2nd paragraph is for temp sender.
Just to clarify since I didn't specify what sender 221-012 was.
Is there someone I can talk to on the phone?
Yeah call my shop 574-546-4656 Tell them that Carey told you to ask for Mike.
