using rb20 harness with rb25 series 1

[preston240sx]

Ok so I have a Rb20 in my 240. I just bought a series 1 Rb25 pretty much complete engine and I was wondering how much work is it to use the my already done Rb20 harness assuming I'd use topspeed injectors in a reflashed rb 20 e c u

[preston240sx]

Wow ... Guess I should of asked on zilvia....

[placham]

Use all the electronics from Rb20 on RB25 with Rb20 harness and ECU, like TPS, CAS, Coils, ignitor, Knock, water temp,O2, $hit its basic. Use all and as many electronic parts as you can, its common sense.

You might have a issue with injectors Rb20 top feed, Rb25 side feed, and their different impedance I think too, if connector plugs fit, otherwise might have to go with Rb26 injectors and fuel rail upgrade.

p.s. you can run Rb26 harness&ecu with some mods (MAf, O2) on Rb20.....

Im sure you'll get same answer on zilvia

[Yellow4g63]

You might want to run the 300zx ecu since it will control the vct vs the rb20 ecu won't unless you plan to run a rpm window switch.

[preston240sx]

I havent read much into the swap but I'm pick up a harness this weekend ...does the 300zx ecu work well or do u need to do some repinning

[placham]

As stated before it can control VCT, and think there's fuel temp feature that has to be disabled from 300zx onto Rb25/20, think there's also some repining involved which isnt too hard. Its a option for Rb25 when doing like NIstune to go with Z32 ecu because of 8bit ecu. Easiest way would be to look at wiring diagram and determine which pins dont match and which have to be moded. Also Z32 runs N62 maf and probably different O2s than RB25. Also there's different things that have to be done between S1 and S2 Rb25s to the ecu going with Z32 ecu.

[Yellow4g63]

I havent read much into the swap but I'm pick up a harness this weekend ...does the 300zx ecu work well or do u need to do some repinning

I'm sure you have to depin the ecu. The injectors numbers will be different. check the nistune forum I think there was a long tread about it.