20v silvertop/adapt ecu & Apexi RSM?

[NIZLAH]

Just a quick question as I cant find any concise answers on the net...

I'm looking at getting an apexi RSM to use (mainly as an 'accurate' speedo) among other things...\\
I just need to know if it will work 'properly' on a silvertop running and adaptronic ecu, and how do I go about hooking it up?

where is the factory speed sensor on a 20v & how does it work, read the speed?

all help greatly appreciated...

cheers
Niz

[Jonny Rochester]

Just looking at RSM wiring diagrams now:


There are 2 main inputs, plus power and earth. Engine speed and vehicle speed.

Engine speed is easy to get, the Adaptronic has a tacho wire.

Vehicle speed is a little hard since the regular AE86 or KE70 does not have a electronic speed sensor, only a mechanical speedo cable. There will be a wire you can use if you have the AE86 digital dash. Otherwise you will need a aftermarket speed sensor, which will probably be fitted to the tailshaft near the gearbox. Talk to a rally workshop about a speed sensor if the RSM does not come with one. Then once fitted, you have to read the instructions and type in numbers relating to diff ratio, tyre size, and number of pulses.

[dr1ft-pig]

niz, your using a w series gearbox yes???

you need an electronic speed sensor from a 6 speed box from behind a beams 3sge or and mx5 (j160)

the speed sensor runs off the gearbox and u will have to swap out the mechanical drive in your box to the electronic one, but u need to swap the plastic drive cogs over which is piss easy

you shouldnt need to run the RSM off the adaptronic at all, although the wires for mine do go through the loom just not into the ecu i dont think

as ant did the loom in mine i dont know whats involved in wiring it up but yeah, its only a 3 pin plug so it cant be too hard, earth, 12v, signal....

i see ant in this thread anyway so he should be able to clear up the wiring it up issue

hope i helped

[Anthony]

nahh all 86 dashes have the speed sender in them.

hook a wire form this wire to the rsm and it should work fine. Even though its a kouki dash pictured, even 4ac dashes have the same pin available.

Steal a pin from another loom at a wrecker or some shit.

[Jonny Rochester]

Thanks for the correction. Right click and save on those pics. I had thought it was reed switch only.

The RSM instructions show the ECU pinouts to use, if you have a 4A-GE vehicle.


Can the Adaptronic b V0.3 use the speed imput, for display and logging?

[Anthony]

it is only a reed switch, but it does exactly the same thing as an electronic speedo sender. It earths to ground 4 times per revolution. The electronic sender uses a transistor to do this, the mechanical speedo uses a 4 pole rotary magnet and a reed switch.

e420b can certainly use the vss input, for logging, idle control, throttle cracking and a whatever else you want to throw at it (speed dependent boost, cooling fan speed etc etc). Ive never plugged a vidigauge into a "b" but i see no reason it wouldnt work. the data packet is the same protocol, just is a bit shorter.

[ke70dave]

hey anthony , just out of curiosity do you know if the ke70 dash has the same thing?

i need to hook a speed sensor up to the jap bigport ecu, my current idea was a magnet/readswitch on the tailshaft.

but if i have that pin as well....i highly doubt the ke70 one does...but maybe you know?

(sorry to steal the thunder from the original poster but seems your question has been answered?)

[Anthony]

As far as I can remember they dont sorry. Yet one more of the many failings of KE70 vs AE86

[NIZLAH]

Thanks heaps lads helped greatly, most appreciated, found all the answers I needed so far...

interesting that all tach dashes have the electric speed signal in them, makes life much easier..

[.ady]

im slightly confused here say i changed my diff to a higher ratio (4.3 from 3.9)and now hav a 4age my speedo is way off about 20km/h (my speedo reads 120 and im roughly travelling 100)....ive got the jdm whiteline cluster also

if i hook up the rsm via the ways suggested above i wud get the same reading as the speedo except digital?

OR

would i get a more accurate reading of the ACUTAL speed i am going at?