Nistune question for RB25 w/ RB20 ECU

[ST240]

I have an RB20 installed in my 240sx right now. I'm going to buy a complete RB25 long block, and use the RB20 harness and ECU to run it with Nistune. Aside from repinning, is it hard to get a base running easily? Is there some method to safely get it going in stock trim (similar to what an RB25 ECU).

[virus77]

Open nistune twice so you have two instances running, one with the RB25 address file and maps. On the other nistune screen open your RB20 maps and address file and copy the main maps and perimeters from the 25 to your 20. This should give a good base. What mafs are you going to be running? If you plan on running z32 I would load the Z32 fuel and K value and use the RB25 timing maps.... this is what I did using a z32 ecu, z32 mafs on my RB25 and it was really good base to start from.

[ST240]

Open nistune twice so you have two instances running, one with the RB25 address file and maps. On the other nistune screen open your RB20 maps and address file and copy the main maps and perimeters from the 25 to your 20. This should give a good base. What mafs are you going to be running? If you plan on running z32 I would load the Z32 fuel and K value and use the RB25 timing maps.... this is what I did using a z32 ecu, z32 mafs on my RB25 and it was really good base to start from.

Ok... So base RB25 maps are readily available from somewhere? Keep in mind i wont actually ever have the RB25 ecu. To start out I'll probably run the rb20 maf since its the same as the rb25 if im not mistaken (what HP does it max out at?). Although i almost should get the z32 maf, its a pretty cheap upgrade.

As an aside, do you know if i can run the injector sub harness from the rb20 on the 25? Ive heard you cant.

[virus77]

nistune will come with a rom pack with all the factory roms you need. You can use whatever mafs you like, I just figured you are getting a nice piece of fuel management, you might as well get the pieces that go with it so you can "utilizher"

Ive never dealt with an RB20 harness but from my limited knowledge they are topfeed so the clips may be different, not sure if they fuel rails swap over... maybe its a good time to get some GTR injectors and that z32 mafs afterall

[ST240]

maybe its a good time to get some GTR injectors and that z32 mafs afterall

ahhaha right you are.