Vehicle speed output

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Pedro
Posts: 30
Joined: Fri May 21, 2010 9:16 pm

Vehicle speed output

Post by Pedro »

Hi,

We have an hatchback gearbox, without speed sensor, to install on a gc8 and would like to know if it´s possible to have a vehicle speed output from the S8 to the speedo cluster.
We have the abs sensors connected to the S8 for traction control.

Cheers
TimH
JT Innovations
Posts: 718
Joined: Wed Sep 01, 2010 3:51 pm

Re: Vehicle speed output

Post by TimH »

Interesting one. I had a look at SCal and can't see any obvious way to do this as I imagine the assumption is that vehicle speed is provided *to* the ECU via a sensor or CANbus. Speed can be made available on the CANbus stream to be displayed on a Toucan or dash product, so it would be possible to create a small electronic module to take the speed info from the Syvecs datastream and generate the necessary pulse stream - but I don't know if such a thing exists?

I could knock one up but the cost of a one off probably exceeds the price of a Race Dash :lol:
Pedro
Posts: 30
Joined: Fri May 21, 2010 9:16 pm

Re: Vehicle speed output

Post by Pedro »

Thank you very much Tim!

I suppose it has to be implemented on the firmware.

Cheers
stevieturbo
Posts: 1321
Joined: Sun Dec 07, 2008 2:04 pm

Re: Vehicle speed output

Post by stevieturbo »

What wheelspeed sensors are you using ?

Not just pair one of those into speedo and ecu ?

I do that with a hall sensor.
Pedro
Posts: 30
Joined: Fri May 21, 2010 9:16 pm

Re: Vehicle speed output

Post by Pedro »

We are using the standard abs sensors.

If they were Hall effect i believe we could do as you sugested.
stevieturbo
Posts: 1321
Joined: Sun Dec 07, 2008 2:04 pm

Re: Vehicle speed output

Post by stevieturbo »

I presume ABS is still active ?

Not sure if there is any useful info here ?

viewtopic.php?f=6&t=553


I guess worst case, you could install a hall sensor somewhere, whether near a wheel or the propshaft and sort a trigger wheel for it ?

Or is there a GPS module that can reference speed ?
Pedro
Posts: 30
Joined: Fri May 21, 2010 9:16 pm

Re: Vehicle speed output

Post by Pedro »

Thank you for your help Steve :-)

Have you tried that solution for vr wheelspeed sharing? If so, it worked ok?

Our idea is to remove the abs completely because we thought that sharing the sensors signal was a bit tricky, please correct me if i am wrong since we would like to keep the abs.

In that case, i believe that we can take the signal from one of the adapters to the speedo, right?

Cheers
stevieturbo
Posts: 1321
Joined: Sun Dec 07, 2008 2:04 pm

Re: Vehicle speed output

Post by stevieturbo »

I havent tried it as my car does not have ABS, and I just fitted hall triggers to my car.

But it will cost very little to try, especially with the yellow relay if you can pick one up second hand

You could try this device too, as think it allows any pulsed input signal, VR or hall, and you can adjust it up/down to calibrate your speedo
Pretty sure you have a choice of output signals too, but it would be a clipped voltage output anyway so safe for almost anything

http://www.jaycar.com.au/productView.asp?ID=AA0376

I used their older version of the kit to make the Hayabusa clocks work off my wheel speed signal.
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