2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

Electronic VSS in Turbo FC3S Transmission

Thread Tools
 
Search this Thread
 
Old May 4, 2016 | 10:54 PM
  #1  
jreynish's Avatar
Thread Starter
New Project on the Way...
Tenured Member: 20 Years
iTrader: (2)
 
Joined: Apr 2002
Posts: 3,764
Likes: 6
From: Yellowknife, NT
Electronic VSS in Turbo FC3S Transmission

So now, the FC3S gets it's electric vehicle speed signal from the speedometer which is driven by the Mechanical cable from the Transmission.

Now, I plan to ditch the OEM Instrument cluster in favour of a SpeedHut set.

I need to figure out the following;

Is there a direct bolt in Speed Sensor that will work in the FC3S Turbo Gearbox?

So far I have found a couple possibilities;
1999-2001 Mazda Miata
2003 Mazda Miata looks like a more suitable fit physically but can not confirm
1996 - Mazda FD3S 5 Speed Manual (I know this one will work by changing the gear wheel, and using some epoxy or brazing) But at $250 USD to modify it seems like a poor choice)

So far this is the best I could come up with. Anyone with some input?
Reply
Old May 5, 2016 | 12:10 AM
  #2  
clokker's Avatar
Cake or Death?
Tenured Member 10 Years
iTrader: (2)
 
Joined: Jan 2007
Posts: 10,249
Likes: 64
From: Mile High
Well, I can confirm that the FD unit will work, but I suppose used FD parts are rather thin on the ground in your neck of the tundra.
I was faced with a similar issue on our Z however, and it was not so simply fixed...or so we thought.

Dakota Digital sells a generic GM VSS (which your Speedhuts would have no problem reading) and adaptor kit (part # SEN-01-1, @$30) which screws on to your stock trans cable drive unit and outputs a signal.

In our case some modification was required, not sure how that would work on the FC.
For $30, it's probably your cheapest option, not as elegant as the FD solution (and the Miata as well...I'd bet they'd all bolt in after you swapped the drive gear) but certainly servicable.

Edit:
If you're going with Speedhuts, why not just get the GPS speedo and bypass the signal problem altogether?

Last edited by clokker; May 5, 2016 at 12:12 AM.
Reply
Old May 5, 2016 | 09:42 AM
  #3  
ACR_RX-7's Avatar
Lacks Ample Funds
Tenured Member 10 Years
iTrader: (1)
 
Joined: May 2014
Posts: 934
Likes: 14
From: PNW
Perhaps he wants to keep cruise or have a speed input into the ECM?
Reply
Old May 5, 2016 | 11:06 AM
  #4  
clokker's Avatar
Cake or Death?
Tenured Member 10 Years
iTrader: (2)
 
Joined: Jan 2007
Posts: 10,249
Likes: 64
From: Mile High
Originally Posted by ACR_RX-7
Perhaps he wants to keep cruise or have a speed input into the ECM?
I don't think that happens if the stock cluster is deleted.
There is a speed sensor output from the stock cluster that sends a signal to the cruise computer, the power steering computer and (for some reason, on S5's) the seatbelt control module.
Silly mousetracks.
Now, what that stock signal looks like, I have no idea...I suppose you could piggyback off the new VSS and send that waveform to the various modules and see what happens.

There does not appear to be any connection of this speed signal to the ECU, so if you have manual steering and can live with no cruise, this wouldn't be an issue.
Reply
Old May 5, 2016 | 11:12 AM
  #5  
Nosferatu's Avatar
Senior Member
Tenured Member: 20 Years
Liked
 
Joined: Mar 2006
Posts: 437
Likes: 28
From: Bear Cage
If you are using a speedhut programmable speedo ...as Clokker recommends ..why don't you just buy the gps speedo (apparently they work very well not laggy like other makes and GPS add on adaptors)? in the end it will cost roughly the same as adapting a speed sensor...the digital Dakota sensor is a imperial thread ..it will shoe horn on the metric thread as it's the same diameter but different thread pitch so you will only get a small thread contact plus you need to get the proper tang or modify the pin to work....but if you are set on using a speedhut type electronic speedo which accepts any no. of VR or Hall speed sensor signals...you are in luck ...took me a while to find this... hall sensor from Toyota and direct bolt on with same tang and metric thread as the FC speedo gear...enjoy


Speedometer Adapter, Mechanical to Electrical, VSS, 301447-1-KIT

Last edited by Nosferatu; May 5, 2016 at 11:43 AM.
Reply
Old May 5, 2016 | 01:14 PM
  #6  
jreynish's Avatar
Thread Starter
New Project on the Way...
Tenured Member: 20 Years
iTrader: (2)
 
Joined: Apr 2002
Posts: 3,764
Likes: 6
From: Yellowknife, NT
GPS speedo is not Legal up here in the great white north. Think Downtown, or in tunnels, or what have you.

Also I want a VSS so that I can send a signal to cruize control, as well as the ECU, i can not do that with the GPS speedo.

Clokker, I read your thread about switching the gear, I think that is likely the way I will go If I can ever get my hands on one to measure it and make sure it will fit.

Nosferatu - Awesome find! exactly what I was looking for! I already need to order some Toyota Plugs and pins for my power steering pump, will just add this connector to the list! Not sure how you found this, but I have been looking for this exact thing for the better part of two months prior to posting this thread! Thanks again!
Reply
Old May 5, 2016 | 04:45 PM
  #7  
Nosferatu's Avatar
Senior Member
Tenured Member: 20 Years
Liked
 
Joined: Mar 2006
Posts: 437
Likes: 28
From: Bear Cage
Glad to help...have to thank clokker though..it was his thread/knowledge that inspired a cluster project that I stumbled on this find.
Reply
Old May 5, 2016 | 07:36 PM
  #8  
clokker's Avatar
Cake or Death?
Tenured Member 10 Years
iTrader: (2)
 
Joined: Jan 2007
Posts: 10,249
Likes: 64
From: Mile High
Thanks, but had I known of your find, I'd certainly have used it on the Z...it's brilliant.
Reply
Old May 5, 2016 | 08:03 PM
  #9  
valley's Avatar
Senior Member
Tenured Member 05 Years
iTrader: (1)
 
Joined: Jan 2012
Posts: 307
Likes: 2
From: VA
Originally Posted by Nosferatu
If you are using a speedhut programmable speedo ...as Clokker recommends ..why don't you just buy the gps speedo (apparently they work very well not laggy like other makes and GPS add on adaptors)? in the end it will cost roughly the same as adapting a speed sensor...the digital Dakota sensor is a imperial thread ..it will shoe horn on the metric thread as it's the same diameter but different thread pitch so you will only get a small thread contact plus you need to get the proper tang or modify the pin to work....but if you are set on using a speedhut type electronic speedo which accepts any no. of VR or Hall speed sensor signals...you are in luck ...took me a while to find this... hall sensor from Toyota and direct bolt on with same tang and metric thread as the FC speedo gear...enjoy


Speedometer Adapter, Mechanical to Electrical, VSS, 301447-1-KIT
Very nice find. Do you happen to know whether it has a PPM or sinusoidal output?
Reply
Old May 6, 2016 | 02:12 PM
  #10  
Nosferatu's Avatar
Senior Member
Tenured Member: 20 Years
Liked
 
Joined: Mar 2006
Posts: 437
Likes: 28
From: Bear Cage
it's a 4k ppm hall sensor...square wave ...not sure what the wave form generated..i.e. if it's just square pulses in positive.
Reply
Old May 6, 2016 | 02:21 PM
  #11  
FC3S_nataku's Avatar
mattg prob nt coming back
Tenured Member 15 Years
iTrader: (3)
 
Joined: Feb 2005
Posts: 1,933
Likes: 0
From: OrangePark FL
would you still need to find or make a harness to use with the adapter or is there another way to connect it to the speed sensor on the transmission?
Reply
Old May 6, 2016 | 02:56 PM
  #12  
clokker's Avatar
Cake or Death?
Tenured Member 10 Years
iTrader: (2)
 
Joined: Jan 2007
Posts: 10,249
Likes: 64
From: Mile High
You'll need to make your own harness to go from the VSS to the new cluster wiring.
On the FD and GM VSS units I've used, there are only two wires- switched +12v and signal to the gauge. Apparently, the Toyota has three wires, so you'll have to dig up a schematic and see how it works (probably +12v switched, ground and signal).

Fortunately, the FC is pretty easy to swap gauges into because of the short jumper harness from the firewall/main harness to the gauges. You can make all your changes to this subharness without getting too deep into the main electrical of the car.
Reply




All times are GMT -5. The time now is 08:07 PM.