clokker

iTrader: (2)

One could be used around the speedo but the tach is larger, so it would remain unblinged.

clokker

iTrader: (2)

While awaiting the VSS from Ben, I've checked the schematics for both the FD and the Miata and confirmed that the NB Miata cluster is wired exactly the same vis a vis the sending unit.
There are two wires (I'll have to source a connector) and they both go directly to the cluster...no external power required, so no interface with the stock harness necessary.

Failing a revelation while under the car, I suppose my wiring will simply follow the route of the stock speedo cable for now, there's no reason to get creative till I know how this works.
I'm thinking it's a total longshot that the readings will be accurate, so it's probable a Digital Dakota box will be required (for those unfamiliar with these, the DD box is simply a signal processor- about the size of a cigarette pack- that you splice between the signal generator and the gauge. Using dipswitches and a chart the speedo or tach can be calibrated quite accurately. This will only be necessary while I keep the rotary engine, the GM ECU can be programmed to make this correction for you, no external devices needed).

Anyone considering this for their car- probably no one...if you like the black face NA cluster (which fits the "look" of the FC perfectly...except for the lighting) none of this nonsense is needed. All you'd need is (probably) the Miata speedo cable.
I haven't confirmed it will screw onto the transmission fitting, nor that it's long enough but I'd almost bet that it would be (or could be made) suitable.
Of course, even if it fits right on, I don't know how accurately it'd read, so there's that.

Only the later NB cluster requires this extra work.

I visited my plastics supplier and they were very helpful with adhesives and suggestions for trimming the gauge face panel, my second effort should be much nicer.
That said, I've shown the current setup to several people (not RX fans necessarily) and they couldn't tell it had been swapped out, so it's not too bad as it sits.

One area that I've purposely ignored is the trip reset post.
The Miata post does not line up with the hole in the RX clear plastic face...naturally, why would it? I did not attempt to address this as I know that these posts are not the same on the NB cluster I'll end up with and I only have two clear panels to play with, so I'm saving them.

Be aware that drilling this clear acrylic plastic is fraught with danger as it's VERY brittle.
You MUST use the special bits designed for plastic.
They have less rake on the tip and won't "plunge" into the cut, which is how the cracking will happen. Well worth the few bucks they cost.

Still looking for a NB cluster I can afford.

RotaryEvolution

iTrader: (30)

the miata transmission is almost identical to the non turbo FC transmission with the exception of the bellhousing also, so i would bet that the speedo assembly can be swapped into the 7 even if the cable doesn't fit it.

clokker

iTrader: (2)

Good to know.
Thanks.

clokker

iTrader: (2)

Good news, everyone!
Well, mostly.

I found my Miata speedo cable and it's perfectly suitable for install on a FC...length is the same and the fitting at the trans end screws right on.
There is one small caveat- the firewall hole must be enlarged to allow the cable end to pass through and the sealing grommet to fit.
Took about ten minutes with a Dremel.
After that it's just like stock, I even used the stock cable clips underneath to hold it in place.

So far I've only taken a short test drive- with no independent speed verification (like GPS)- but the speedo seems to read quite closely to stock, at least it seemed consistent with the speed limit and surrounding traffic. If it's off, it's not by much.

So basically, as far as an untouched Miata cluster and a stock FC install goes, that's it.
At this point all the gauges work* and the appropriate warning lights are all functional.
TBH, I didn't expect to get this far this easily.

While I gather the funds necessary to purchase the NB cluster (which I think is the one I want to end up with), I'm tempted to go a bit further with the current setup.
*The oil pressure gauge in this unit is wonky, I've checked the wiring multiple times and have decided it must be the gauge itself because the FC gauge works fine.

By "a bit further" I mean replacing the bad oil pressure gauge and the numb water temp gauge with some VDO units that I have.
This presents some cosmetic challenges but preliminary inspection shows it should be relatively straightforward.

We'll see how this goes...

clokker

iTrader: (2)

Turns out, the gauge is not bad, it's "wonky" by design.
I tried to track down specs for the '99 Miata oil pressure sending unit and...turns out, they don't have one.
Instead, they have a "switch" and the gauge is fake...it'll tell you that oil pressure exists but not how much. The switch opens and the gauge reads "normal" at 7PSI, after that it doesn't move till the engine is shut down.
I believe that the water temp is much the same (think: S5 gauge).

The NB Miatas (white face gauges w/electronic speedo) do not suffer from this, at least, the OP gauge is functional (if heavily dampened). There are writeups detailing how to "linearize" the water temp by adding some resistors but I'm unsure if that applies to the NA gauge as well.

Apparently there are replacement, "real" gauges available from Mazda Comp, drop in replacements that read correctly (after you replace the sending units). I saw a price of $37 for the oil pressure gauge, not too bad really. I'm not going to get one since ultimately I don't plan on using this "prototype"...and I have some VDOs that I'm willing to sacrifice.

Adding the VDO units into the cluster presents several challenges.
They are not going to match the Mazda look/coloring and mounting depth might be a problem.

To mitigate the visual issue, I think the VDOs would have to go at the outside corners of the cluster, which gives a group of three matching faces in the center flanked by the two new parts.
Of course, this means that the fuel level gauge must be relocated to the top center where the OP is located now. Surprisingly, it looks like a direct drop in- the mounting bolts (which also serve as electrical contacts on the circuit board) are identical but there may be issues with the light diffuser (pics later if I get that far), so I'm not sure.
Assuming this internal swap is possible, the next issue will be figuring how to integrate the VDOs into the corners, which would have been a whole lot simpler before I glued the two bezels together.

I have a VDO voltmeter pulled from a VW in the junkyard that I'm going to sacrificially dissect to see what I'm dealing with internally.
Might give me some ideas.

clokker

iTrader: (2)

Adventures in oil pressure display, parts 1-3.

"Might give me some ideas", indeed.

As I began studying the gauges again this morning, a weird and compelling little sign beckoned.
The dial mount screw locations seemed identical on the the Mazda and VDO gauges (turns out they were very close, but did require enlarging a bit to be perfect) and from this seemingly inconsequential detail, the project again lurched into action.

One "I wonder if..." lead to another and three hours later,almost before I knew it*, the VDO gauge had replaced the dummy Mazda unit, using the Miata dial, needle and lighting diffuser.
I'd take a picture but it looks just like the original...except it works.
I ran the gauge wiring out the top and down the back where it screws into the stock terminals on the printed circuit sheet, so there's no extra wiring to connect, it's all running through the original circuits.

It was success through a thousand cuts as I artfully Dremeled the VDo's plastic body so it is gracefully wedged into postion (a deed made easier due to the locating holes in the Miata dial). So far it has no adhesive, tape or mechanical fasteners...I think it'll be fine but time will tell.
I am now sorely tempted to do it again with the water temp gauge.
Yikes!

*"Three hours, before I knew it" speaks volumes about the confluence of curiosity, some spare time and med grade weed.

AGreen

iTrader: (11)

Yep. Miata (at least the NA miata, never worked with an NB) oil/water gauges are a go/no-go gauge. Well, I guess their water temp gauges have 3 settings: cold, warm, and "you're buying a new engine".

I had to google what "vdo" gauges are. I didn't know that you could swap the physical gauge out in the cluster, I'd like to see some pictures of that.

clokker

iTrader: (2)

Well, I'm pretty sure I'm going to swap in the water temp too, so I'll take some shots then.

clokker

iTrader: (2)

All done.
Another morning spent and new challenges overcome, but it's nearly finished.

Here you go, Mr Green...

Start with the VDO gauge that graciously consented to being carved up:




The stock (pretend) Miata water temp gauge, removed from the cluster housing:



That clear tongue-looking thing hanging off the side is the light diffuser. The tip of the tongue sits right over a bulb and carries light up to the dial and needle. It's going to be a problem...

...that I wasn't aware of yet.
First, the VDO had to be freed from its housing. The easiest way to do this is just dremel the plastic body off, about a third of the way down. Care must be taken because you don't know what's inside till you crack it open and you don't want to accidentally zizz something important.
Here is the VDO decapitated:


And naked (WARNING! potentially NSFW bare gauge on gauge action ahead.):


At this point I ran into the diffuser problem. The part that curls down to the bulb interfered with a component of the innards. Took some grinding to create a relief in the tongue that would pocket the resistor that was in the way. This was not necessary for the oil pressure swap, and indeed, will be completely different for every brand of gauge. Just be prepared for weirdness.

It did go together at last:


Then dumped into the housing:


And wired:


Those clever Japanese use the stock gauge mounting points as the contacts to the circuit sheet (the Miata- and most later cars from what I see- uses a flexible sheet instead of the FCs hard circuit board) and naturally, the VDO doesn't have these...there is nothing to screw into.
Since I just needed to make contact, I found that computer fan screws were ideal to thread into the ABS housing. Stuck the wires on the contact pad and clamped 'em down with the computer screws and washers.
I should have used eyelets but didn't have any.
Sue me.

Since I'd gotten so much further than I expected, I decided to go for broke and make the trip reset functional. This required drilling the FC clear plastic face (nervewracking!) and making an extension to bring the Miata pushrod out far enough.
I briefly considered dismantling the speedo and crafting a new part altogether- or possibly adapting the FC rod, but decided that was a can of worms I wasn't up for.
So I just turned a rod that slipped over the Miata part and extended it properly.
Painted it flat black and although not particularly elegant, it's not awful and it works.


And done!


Two things I learned that will be of use should anyone do something like this.

-I had this VDO gauge/sending unit installed before, with a standalone harness. This time though it's using the stock FC wiring and it was VERY slow. It finally occurred to me that I still had the stock FC condensor in the circuit (the little black box bolted to the slave cylinder...that almost no one still has but me, apparently), disconnecting that solved the problem.

-This procedure requires removing the gauge needles and it's going to be difficult to get them to correspond with the new dials, particularly the water temp.
Here's what I ended up doing:
Remove the needle (or be smart and don't install it till you reach this point...)
From a cold start, it's easy to tell when your temp reaches 180 because the idle drops to 750rpm.
My efan is set to initialize at 195 (verified previously with this very gauge), so I waited till the fan kicked in and placed the needle pointing straight up.
My thinking is that this places the needle normally somewhat below halfway, with straight up being the outer limit of my comfort zone- i.e., the fan should be starting.
Hard to tell in this cold winter weather, I may need to readjust come summer.

Now I get to repeat-hopefully with cleaner results- this whole thing with a set of NB gauges.
Fortunately, none of the originals will need the VDO treatment as Mazdacomp offers a drop in replacement oil gauge (for a quite reasonable $40) and there is a mod for the water temp that only requires a couple of additional resistors...much preferable to the hacking/fitting of aftermarket stuff.

So, until I get the NB cluster, that's it.

Just for the hell of it, you might enjoy my custom Honda computer chair...

AGreen

iTrader: (11)

And the Honda chair is awesome too

RotaryEvolution

iTrader: (30)

nice work!

keep us updated on the later model cluster as that is the one i would prefer to go with.

clokker

iTrader: (2)

Thank you and I shall...your donated VSS will not be in vain.

I have big plans for the v.2 attempt.

RotaryEvolution

iTrader: (30)

i'm getting tired of the stock gauges, maybe this will give a new feel to the car. heh

clokker

iTrader: (2)

It won't but it will give your eyes something new to look at.
Also, as Bamato pointed out, much of the stock warning cluster could be integrated into the warning panel in the gauge unit, were one so inclined.
I haven't really looked into that but may when I begin with the NB unit.

clokker

iTrader: (2)

Update:

The NB cluster I bought was not as advertised and I sent it back (it was for an auto trans and did not have the advertised pigtails).
Still looking for an affordable unit.

Meanwhile, a few observations...

I need to trim down the VDO housing around the oil pressure gauge for better lighting on the dial. The needle is well lit but the dial face apparently needs more ambient light from the main bulbs.
I thought the diffuser handled that but apparently it's more for the needle.
Oh well.

The speedo completely fritzed out while driving the other day...loud grinding noises and the needle went crazy, spinning all the way around.
Oddly, the odometer continued to work normally.
After stopping at few traffic lights, it suddenly began to act right and has done so since.
I have no idea what happened.
The cable I installed was lubed beforehand , spun freely and showed no signs of damage, so I don't think that's the issue. Besides, if the cable was failing I wouldn't expect it to "fix itself", it should get worse.
That said, I can't imagine what would cause the gauge to act so strangely and even odder is why the odo wasn't affected.
Just have to see if it happens again.

When the speedo IS working correctly, I think it reads a little high but haven't checked against anything yet.

Energized with my semi-success with the gauges- and the lack of a NB cluster to continue with- I'm back on the longstanding FD dash project.
This ain't the place for that but I'll tease with a pic of what we're doing...


Basically, the entire dash/center stack and trans console are all being custom made.
That center stack is from a MX-6 (got the whole thing, including the factory stereo, for $90) and it is completely functional in this pic.
The stereo/CD works (and sounds really good!) and all the heater controls have been adapted and function correctly.
This is only at "proof of concept" stage but it's looking promising.

clokker

iTrader: (2)

Narrowing down my search, have four options (including a new darkhorse candidate!).

#1- my original choice, 2001-2005 MX-5, red illum.


#2- same as above but from 1999-2000, black dials, green illum.


#3- 2006-2008 Miata, red illum.


#4- 2003 MX-6, red illum.


So, here's what I'm thinking...
Options 1 & 2 are known quantities.
I've already prototyped the conversion and have the wiring diagram (but not the pigtails).
The white faces are more modern looking and the red lighting would be a close match to the rest of the switchgear. The black faces are almost dead ringers for our stockers and I like the green lighting but acknowledge the mismatch with everything else.

Option 3 interests me because of the construction. Each gauge has it's own glass, there is no big clear cover plate. That might be easier to meld into the switch bezel without using any of the stock cluster pieces.

And finally, option 4.
This thing is nearly identical to the stock cluster. The overall shape is much closer than the "triangular" Miata parts and the front glass is laid out exactly the same (sloping out at the bottom). It looks like it would slip right in (I'm not naive, I know it won't but it sure is closer than anything else).
I find the layout quite striking but can't decide if it's appropriate in the context of the '80's dash we have and of course, there's no oil pressure display.

Any thoughts- beyond "The tach should be in the middle!"*- appreciated/considered.

*For those in this camp, I would direct you to a nice Ferrari display- GIANT YELLOW TACH, dead center- which you could probably pick up for a mere $10k or so.
That would be a thread I'd watch, for sure.

clokker

iTrader: (2)

More musings on the MX-6 cluster:

My thoughts on gauges have been morphing of late.
At one time I was all about extra gauges, had VDO oil pressure & temp, VDO water temp and a VDO analogue clock.
I then went through the process of locating all this new display- first, in the center console, then up to the warning light display area and finally, tucked around the main cluster (two in the corners and one on top of the column surround).
Only the last was acceptable, the first two locations were too far out of my comfortable line of sight.
That's one reason I started looking at these different gauges...I wanted a clearly legible and unobscured gauge layout.

Concurrently, I've been blathering on (as I'm wont to do) in threads about aftermarket gauges- my take being that the popularity of multiple data displays is, A) inefficient and B), vaguely insulting.

It's inefficient because more gauges to monitor means more time not watching the road.
This is why warning lights are so popular with racers- you don't have to think about a parameter (like water temp, say) until a critical level triggers a light. No light= OK.
Also, you don't have to monitor a light as you do a gauge, it'll grab your attention when it needs to whereas a gauge can go to full panic unobserved, if you're otherwise occupied.

It's vaguely insulting because it implies either the car is so fragile that unless you're glued to the gauges with your hand on the key it's gonna grenade, or that you so consistently run it at the edge that your sheer awesomeness could destroy the engine.

Admittedly, in some cases one or both of these may be true for a very good reason...but not many, I'd wager.

So, not only does the MX-6 cluster offer an easier installation (I think) but it would also force me to put my money where my mouth is.
There are enough extra warning lights that low pressure/temp warning systems could be easily implemented and I'd subject myself to the opinions I've been offering others.

I need to confirm some data before moving forward.
Primarily, I need to get to an ALLDATA access point and find out the specs on the MX-6 fuel level sending unit. Our sending units (the RX-7 and the Miata) read opposite of most and I need to know that the MX-6 does as well. Minor variations of the upper/lower ohm range don't really matter but I'm not willing to extend this project all the way into the gas tank by replacing sending units.

All of these clusters will require installing the FD VSS to run the speedo.
I'd like to confirm the wiring is similar for these later model gauges, I'm already pretty sure it'll be fine on the earlier stuff.

So there.

Flash

iTrader: (2)

Very interesting. I love your DIY work. I like the tach in the center, but your way of updating the interior is sweet.

As far as your choices I like cluster 3, not only for individual glass, but I like the needle style more. Looks more modern IMO.

clokker

iTrader: (2)

"Needle style" being the way they hang straight down at rest or the indicator itself?

I must admit that #4 is really growing on me.
Has kind of a HAL9000 look going on....

clokker

iTrader: (2)

To further confuse the issue- and satisfy Karack- the 06-07 MX-6 Turbo cluster has a 180 mph speedo.
I don't like the styling as much as the more blacked-out earlier models.

Slideways FC3S

iTrader: (1)

Any update on the beauty and creativity that is going on in this thread. My seat is breaking as I'm on the edge still waiting to see more. I don't know which one I like best, but I know I would like the needles to glow red, the numbers and speed ticks to be lit up white except for high, low marks and redline numbers and ticks would be lit red, if I had my way with it . Not having the Tach in the middle is a little weird but I could get used to it. All in all I love the creativity in your projects, keep up the awesome work.

suck_my_rotor

iTrader: (8)

I love the fd gauges, however I like the miata gauges too, just not the green, ugh! If there was a way to do the miata gauges with the fc orange, that would be awesome

clokker

iTrader: (2)

Sorry, the FC has taken a backseat to the FD dash project as I try to take advantage of the warm weather we're having.
There IS going to be a small update soon on this job, maybe as soon as Friday.

Thanks for your (chairbreaking) interest.

JerryLH3

iTrader: (11)

I wasn't on the forum much the past few months, so I'm glad this thread got bumped. It's provided some inspiration for me as I try to tackle how to go about my instrument cluster in my TII resto project.

I love the FC gauges and think they are fine just the way they look. It fits with the rest of the car and the era it was around in. For my FC though, I had also tossed around the idea of ditching the stock cluster and upgrading to modern gauges that would function better, but I hated losing the look of the stock cluster - especially since I am not very flashy and like things mostly stock.

Post #35 in this thread seems to have given me some ideas. It could be entirely possible to do the same thing to a stock FC cluster with at bare minimum the water temp gauge. I had VDO gauges in my old N/A and liked them. They are cheap and seem reasonably accurate. The sweep is also around the same as a stock FC gauge. And I do have a spare instrument cluster laying around to tinker with.....

Kudos on the tinkering. If someone didn't know what FC gauges looked like from the factory, they would assume those were it. The NA and FC were close enough to the same time period that it doesn't look out of place.