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Safc Dec Air Tuning

tmc_2

By tmc_2,
in Tutorials / DIY / FAQ

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tmc_2 Rising Star

tmc_2

Posted
Posted (edited)

Hi guys,

Those running ATMO BOV's will know the problem of stalling between gear changes.

Now the APEXI SAFC 1,2 and neo should all be tuned by a professional on the dyno for best SAFE results.

You can however tune the 'dec air' function of ur safc with no problem following this guide outlined below.

I have done htis to my r33 and have great results.

DEC AIR SETTINGS

""when the car is completely cool start it up. have the safc mointoring throttle %, air flow, and rpms. have the engine at 1000rpms and write down the air flow. then have the engine at 2000rpms and write down the throttle % and air flow.

now go to the dec. air settings. the THR setting is the throttle % you documented at 2000rpms. the NE1 setting is the air flow you had at 1000rpms. the NE2 setting is the air flow you had at 2000rpms. this will get you very close to the settings you need. may not be perfect but very close. this will allow you to run an atmospheric bov without stumbling between gears""

One thing i do different- I set my Thr% to 1%. this basically tells the safc that when there is less than 1% of throttle to use the 'dec air' settings i have outlined, have had no issues with this so far.

This will not effect the rest of ur drving or ecu maps, only the off throttle so u car wont stall any more.

Side note- The SAFC is a useful interceptor piggy back computer. However If tuned incorrectly with out proper tools or knowhow can casue major damage to your engine.

I have Used this method for DEC AIR wiht great results.

:)

Edited by tmc_2
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tmc_2 Rising Star

tmc_2

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Can this also be done on a PFC?

Hi Kennedy,

From what i know the PFC controls this as good as or better than the SAFC.

I dont know how to tune one or what its called on a PFC as i have not yet had the opportunity to use one.

I would think a PFC would have a much more wholesome method of controlling 'dec air' settings as well as other engine conditions.

If your having trouble with that metal intake pipe causeing stalling maybe try getting ur pfc tuned and emphasise to the tuner why.

I had constant stalling issues after installing the metal intake pipe. I installed it corectly and have no leaks.

With my SAFC NEO tuned using this above method and stopped it stalling completley.

Let me know how things go.

Kennedy Mentor

Kennedy

Posted
Posted
Hi Kennedy,

From what i know the PFC controls this as good as or better than the SAFC.

I dont know how to tune one or what its called on a PFC as i have not yet had the opportunity to use one.

I would think a PFC would have a much more wholesome method of controlling 'dec air' settings as well as other engine conditions.

If your having trouble with that metal intake pipe causeing stalling maybe try getting ur pfc tuned and emphasise to the tuner why.

I had constant stalling issues after installing the metal intake pipe. I installed it corectly and have no leaks.

With my SAFC NEO tuned using this above method and stopped it stalling completley.

Let me know how things go.

The car has been tuned and I asked hitman if he could "tune" it out but he said he cant.

Bearing in mind that my car only has hunt issues if I dont make boost. eg...when putting around a car park and stuff. If I'm giving it then slow down and shift down/slip into nuetral then the car idle drops brack straight to 800rpm and stays there. It only happens when RPM doesnt exceed around 2K RPM

tmc_2 Rising Star

tmc_2

Posted
  • Author
Posted
The car has been tuned and I asked hitman if he could "tune" it out but he said he cant.

Bearing in mind that my car only has hunt issues if I dont make boost. eg...when putting around a car park and stuff. If I'm giving it then slow down and shift down/slip into nuetral then the car idle drops brack straight to 800rpm and stays there. It only happens when RPM doesnt exceed around 2K RPM

Hmm must be something to do with how ur intake return pipes are. I don thave any hunting issues now i have secured a decent BOV return and iol breather return.

Id say thats wherer the problem lies.

  • 2 years later...
  • 3 months later...
r33canada Community Regular

r33canada

Posted
Posted
bump,

can this be used to elimitate the plumback function altogether? upgraded to a bigger turbo and didnt think about the plumback :) , so car stalling all the time.

yes, this is for if you have an aftermarket blowoff valve that vents the excess air out instead of the stock bypass valve returning the unused air into the system.

it would help with the stalling but what also helps is bumping your idle up alittle.

nothing will be perfect for cars that are not meant to vent to atmo, only cars that run on a map sensor instead of a maf like us will not stall.

what are you using for a blowoff valve?

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