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Power FC D-Jetro? How Hard to tune?

underground

By underground,
in General Automotive Discussion

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underground Collaborator

underground

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Hi,

We are doing the R33 RB26DETT motor swap into a US Spec 1998 240SX (S14), and we are going with the Apexi Power FC. I know that the D-Jetro uses the MAP sensors, which would be great for the ultimate tuning control, but does anyone have experience with the tuning?

I have talked with several shops in the USA who won't tune it unless we convert to a single throttle body setup. Could anybody share their knowledge or recommend a better setup?

Thanks!

Chris

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Corse Apprentice

Corse

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I would use a standard or Pro PFC with upgraded AFM's with the 6 throttle setup intact, as removing these as you probably already know sacrifice fuel economy, but more importantly off-boost drivability and throttle response.

you have already decided to take the first step in degrading your throttle response and drivabilty by using the D-Jetro, so you may as well convert to a single throttle body as well.

The 6 throttle setup is known to make tuning tricky, as the standard throttle body causes some kind of inlet pulsation which the MAP sensor picks up as rapidly fluctuating air flow - This is why most tuners have trouble tuning this setup, however it is very possible, to tune using this setup as it has been done many times before.

At low RPM/airflow levels/load, tune using the TPS versus RPM with the MAP disabled. On boost, at higher RPM, the pulsations will start to diminish and this is where you use the MAP sensor for tuning inputs.

As i have no experience tuning the D-Jetro, i do not know if the D-Jetro is able to do this, but this is apparently the solution.

Hope everything works out :(

edit: this information is mostly second hand and could be incorrect. this is an internet forum, so i hope i dont need to tell you to check the facts first :)

underground Collaborator

underground

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sorry to be off topic but can i ask why dosnt usa have any silvia s15 cant they import them or anything

None of the Silvia's can be imported as the SR20DET motor does not meet emission standards here in the USA. Motorex has been able to import the Skyline after years of tests, etc. Nobody unfortunately is going to go to the expense of crash testing a $15000 car...I wish they would, it would be my dream car....

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