R31 Speedo Drive Question - Rb20 Box

[Simon-S14]

gday all, I just put a RB20 box into the 31 and used the 20 electric speedo drive since the R31 one was rooted. Now the 20 drive has a 2 pin plug that does not match the 3 pin plug of the 31 drive so i cut them of and soldered the wires together.

However the RB20 drive has two wires, a Black and a Green while the 31 loom has 3 wires, black, red and a yellow (with a blue wire further up tapped into the red wire) So i wired the Black to black and Red to the green on thge loom to the RB20 drive.. and just taped up the yellow wire.

Now the speedo does not work until about 40 kph, where the needle suddenly works and reads very inaccuratally (at 60 kph it says 140 kph)

any idea's what i need to do to make it work, or should i just get a 31 speedo drive.

Cheers

Simon

[NismoR31Jet]

Just get an R31 speedo drive.

[RB20_ZED]

if i were u, id take off the gearbox connection, hook a multimeter up to the wires and spin the little nob in the gearbox connector by hand to see what output the wires have...

u mite see that the red/black combo puts out current in one "spinning" range and the black/yellow in another... i.e. u may need to connect both the red/yellow onto the green...

BUT this is just my thoughts...