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Apexi Safc? Up To The Task?

51OWW

By 51OWW,
in Engines & Forced Induction

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51OWW Enthusiast

51OWW

Posted
Posted

Hey all. I've got an rb20det in my silvia.

Has:

high mount manifold

rb25 turbo(Modified to use external gate)

external gate (14 psi spring)

Front mount

3"exhaust

walbro fuel pump

sard fuel pressure reg.

(Car doesn't drive atm... just has these things fitted)

I have an safc 2 sitting in the garage, will the safc be able to cope with this setup? (Will it be able to handle a minimum of 14 psi due to external gate? (Not planning to run more then 14psi on rb25 turbo :)))

If required, does the safc cope with changing injectors/afm???

Ta.

Chris.

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sidewazegtst Collaborator

sidewazegtst

Posted
Posted

The SAFC is ment as a piggy back system to trick the ecu and since your using an RB20 ecu you don't need to trick it. It's ment to see boost and to run 270cc injector's which are in your motor.

Now those injector's won't handle 14psi for very long as you are just (if not for sure) maxing out the duty cycle and an SAFC won't be able to fix that problem. A boost controller, along with the rest of your set up, will allow you to run 10-12psi ish and be fine. You can wire it in if you want and yes you can add some fuel but only a dyno will be able to determine the correction needed. So if you do install it make sure to leave your LOW & HI throttle maps at 0% +/- as that will have the injector's work normally.

If you plan on using larger injector's then YES you'll need some sort of fuel management at that point along with either a dyno tune or a tune from someone with a wideband to make sure your a/f's are good. The SAFC will be fine for injector sizes up to 550cc. Some people have run those with no problems while others have said they can't get the right settings and needed more of a stand alone system. I guess it's all a matter of getting lucky.

Well I hope that helped you out and good luck with your project. ;)

Cheers B)

PlasticStan Enthusiast

PlasticStan

Posted
Posted
Now those injector's won't handle 14psi for very long as you are just (if not for sure) maxing out the duty cycle and an SAFC won't be able to fix that problem. A boost controller, along with the rest of your set up, will allow you to run 10-12psi ish and be fine. You can wire it in if you want and yes you can add some fuel but only a dyno will be able to determine the correction needed. So if you do install it make sure to leave your LOW & HI throttle maps at 0% +/- as that will have the injector's work normally.

He can't run less than 14psi because that is what spring is in the wastegate, doesn't matter what you set the boost controller to.

If it was me I would go for a PowerFC with some larger injectors, much safer than running everything maxed out.

The problem with the SAFC is it doesn't allow any tuning of ignition, infact because you're messing with the AFM voltage, it can result in too much ignition advance, meaning it's always a comprimise with tuning the afr's.

Also I'm pretty sure the ceramic exhaust wheel on the turbo would be haveing a very hard time if your running at 14psi all the time. Maybe you should consider a turbo rebuild as well.

51OWW Enthusiast

51OWW

Posted
  • Author
Posted

Dont mind if everything is running maxed - as long as it can cope with it. (Dont' want to put it on the dyno, find out something can't handle, buy that thing, put it on the dyno, find another thing etc etc)

Would rather just have it all there and ready. Don't want to run more the 14pis. (or less :D)

I s'pose that it's always going to be a touchy subject as most people get different results etc - so i might just have to bite the bullet and see if the safc can cope with what i want on std injectors, if not - new injectors for me, and an safc will be up for sale with all of 15 minutes dyno use haha...

Thanks.

Chris.

black_32 Enthusiast

black_32

Posted
Posted

should easily be able to handly it i ran an rb25 turbo off an r34 fmic gtr fuel pump malpassi rising rate fuel regulator and 3" turbo back on stock comp at 14psi everyday and occasionaly on 16psi and never had an issue so at least with an safc it will be a bit better

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