Wiring Rb20 Silver Top Into R31

[-scooter-]

Hey guys,

i am currently putting an rb20 silver top into my 87 r31 gt import (orignal motor was an rb20 red tops nics).

I just have some questions that i need answered please.....

1. how will i wire the standard tacho to the new computer?

2.i have ABS, will this be affected

3. will the vechile wiring (eg. starter motor, alternator etc) be the same to hook up to the new rb20?

Aso i brought the motor from a wreckers and it is fairly clean and looked after but i am just wondering wat u should do to a motor from a wreckers (eg. give major service test injectors and coil packs etc)???

Wat oil and coolant do u guys run in your motors?

Thanks

Dan

[BHDave]

This will be a bit vauge as i'm not all that familiar with the red top engines.

If the current engine is running coil on plug ignition (which i think they do) then there's a fair chance that the tacho signal is coming from the ecu which is the same as in the r32 ecu so it should simply be a matter of splicing the r32 output into the r31 dash loom. Otherwise you will have to find where the signal is picked up on the existing loom and add that into the r32 loom.

The abs may be affected. The r32 has abs outputs but they may not be compatible with the r31 outputs. I'm assuming the r31 runs a separate abs computer with inputs from the ecu. You would need to find the wiring diagrams for both the 32 abs and 31 abs to see if all the signals are there as a minimum (whether they are compatible will be a different story).

The body loom should be pretty much identical, you may need to swap a few plugs around and add in a plug for the factory oil pressure sender (if you want to use it) but thats about it. If you want to keep your existing power steering and AC compressor it makes it a bit easier too.

Edited September 5, 2005 by BHDave

[blind_elk]

Dave,

I don't believe the ABS and the ECU talk to each other at all (in the AWD models, the ECU and ATTESSA talk TPS to each other, though).

Dan,

In the R32, the tacho signal to the ECU unplugs from the main ECU loom, so presumably does the same in the R31. Worst case, find it and plug it into pinout #7.

The starter and alternator should work exactly the same. In the worst case, you might need to fit the alternator off the red motor onto the silver motor.