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Problems tuning my RB25?

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S2 RB25 from an R33. 


12lbs, stock turbo, FMIC, ISIS intake, 90MM TB, Z32 ECU with Nistune Type 2 board.


Basically my RB25 is running like hot garbage using the stock RB25 map that comes with Nistune and I was wondering if the maps Nistune supplies might be incorrect?


The car loses a lot of power on the top end because the timing is getting pulled back so hard. Does anyone know if this RB25 timing map is correct? It's the stock rb25 map that nistune provides and I don't understand why timing is getting cut so aggressively towards the top end. 


Edited by CGraves

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i'm pretty well versed in nistune tuning. 


The stock rb25 maps go way retarded up in the 96 range as a safety measure incase someone experiences boost spikes or tries to run too much boost. The stock ECU is also known to have a huge dead spot from 44-4800 where they pull timing near peak torque. 



1) are you running stock injectors?

2) are you running stock MAF?

3) do you know what your peak "load" value is (like somewhere between 80 and 90?)

4) what have you done for knock sensor? did you stub it out with a resistor? The RB25 knock sensor used on the z32 ecu is too sensitive and leads to false readings and pulls lots of timing.

5) did you adjust the K-constant at all during first running. Ideally what you do is drive while datalogging and get the long-term fuel trims to be close to 0.

5b) are you using the Feature pack maps?


if you send me your tune and any logs you have, i could have a look at any problems.


email me for fastest response. it's my hybridz username @gmail.com

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