FE-FC Holden Discussion Forum

hi all i am puting a vs v6 commodore engine in a fc holden i am keeping the fc dash .i would like to know what i have to do for a speedo .thanks gary.

 That depends entirely on what g/box you to plan to use ?

i will be using the auto that came with the engine.thanks gary.

I'm not familiar with the auto but does it use a cable or electronic pickup for the speedo ?

hello.it is  electronic not cable . i need to know what i have to do to use fc speedo . thanks gary.

Hi Gary,

welcome to the site.

There are a few ways to hook up a speedo, but not necessarily the original one.

You can use a pulse convertor which can then be used to supply the required pulse to an an aftermarket electronic speedo.

The problem exists in the OEM speedo in that the commo speedo has a "divide by 5" circuit which divides the provided puse by 5 then supplies that to the OEM speedo.

I forget now how many pulses are required but it did require me to run 2 pulse senders.

EFI management system. This is called the Vehicle Speed Sensor (VSS), I then piggybacked a cable driven pulse sender which fed the speedo (Classic Instruments).  I guess you could piggy back a cable to drive the original speedo but I’m not sure if the gears for the speedo drive would be the correct calibration for both the required pulse and cable.

You can get VSS senders from Injection Connection (Perth) around $120 – 140.
The piggy back cable drive and pulse sender and speedo I used were from Classic Instruments.
A 5 inch diameter speedo will slot into the original dash with minor work.

Hope this helps

Cheers

Ed

I wonder if its possible to fit an extension housing off an earlier T700 or T400/T350 with the speedo drive and use a cable ? this is theoretical of course.

not sure if it's of any benefit?

if you're using EFI, you will need the VSS.

just piggy back a cable off the back off your VSS and make any calibration adjustments by re-marking your stock speedo accordingly.. lots of people take them apart to paint so moving your numbers a bit shouldnt be too hard.  Cable would be easy to get made by autocables.

you may be lucky and it may all just fall into place??

Just an idea

Cheers

Ed

 For the OP maybe, i have a carby V6 and celica 5spd so no electro gizmo problems for me  ;)

you really need/want EFI.. ask Cajeriedoc or Smithy!

what state are you in?

Cheers

Ed

hi. ed thanks for your comments. i am in victoria .thanks gary.

no probs gary,

I did compare T400 and 700R4 speedo gears at one stage but i cant remember anything and didn't make any notes.. that didn't help you did it?

I know fatboy has easy access to a T400 speedo gear, he could help if you were really curious.

Cheers

Ed

hi ed i am sure someone will know what i have to do there is plenty of advice given on this site . thanks gary.

sure thing...  :-X  ???

LMAO @ Ed's comment ;D ;D ;D