Hi guys new to the fd scene and engine has gone after 7 months of owning , im buying another engine recently rebuilt and good compression only problem is my car is on a 16 bit loom and engine has a vaccum pack from a 98 car. How much of a pain is is to swap the engine wiring harness over and the ratnest delete to the new engine and ehats the best way of going about it cheers.

 

Should be a simple swap, differences there will be the oil pressure sender on the rear plate won't have a a connection on your harness - you can leave the sender there, or plug (probably BSPP thread, if the other engine has been tossed out entirely). If the engine comes with a water pump, one extra sender that your harness won't have, again leave, or a swap will fix that. If running the oil pump, swapping the Mikuni for the Denso, depending on the ECU set-up might be good.....not sure of connector requirements there.

 

mechanically, they are the same other than the minor differences mentioned. 8 and 16 bit only applies to the electrical. you will simply swap everything from the old motor to the new motor

 

I've done this in the other direction, I bought a newer 1997-ish engine (with 16-bit ECU harness) and installed it into my 1994 car. I removed the 16-bit harness and 'black box' style solenoids, and installed the original 8-bit harness and 'rats nest' style solenoids.

 

I am a bit confused. I think 16 bit systems (with "rat box") were introduced late in 1995 for the version 4 cars and later. So a "98" car should be the 16 bit set up. Having said that, we tried my Version 5 OEM ECU into a Version 4 car and it would not run it. My understanding at the time, the ecu was stymied by just a small variation on the wiring set up (possibly related to the air conditioning).

[Or it might have been the other way around, a Version 4 ECU not running a Version 5 car.]