Would I be able to use one of these SAFC for my NA->Turbo conversion? What are the advantages/disadvantages compared to the newer SAFC and SAFC2?

 

If I recall the originals only had 5 adjustment points, which made being precise rather difficult, the newer ones had more (8 on the SAFC and 10 or 12 on the SAFCII IIRC, check the website)

 

I figured that was one of the bigger differences. From a basic tuning standpoint, how bad is it to have that next switchpoint at 4000 since our secondaries kick in at 3800??

 

It doesn't really effect it, the injectors will stage and come on the same, they just inject more or less fuel as they do it. Really the only time you run into troubles staging is if you have larger secondaries and you don't have fine resolution with the SAFC (though, even if you do, you can still sometimes noticably feel when they come on, either as a dip in power or minor hesitation until the ECU corrects via the SAFC), or you have a standalone and play around with the percentages and timings.

 

So for my predicted setup of 550 all around, this controller would work fine? Thanks for the replies Sonic.

 

Yep, what ECU are you going to use? The N/A ecu can be a little tricky at times with an SAFC, starting and warming up tends to be pig rich regardless of corrections, then once warm it runs rather fine. I usually suggest converting over to TII electronics if possible.

 

I was going to stick with the NA ecu and adjust for -X% on the low end pre-2400ish and then make proper adjustments higher for boost. I was actually hoping to lean the idle out a bit.

 

Not recommended...

Your stock pressure sensor clamps at "0" manifold, so it doesn't know you're seeing boost or not.
At least the turbo boost sensor reads up to 15psi, and the turbo ECU backs down ignition timing depending on how much boost.

I dunno how reliable the non-turbo pressure sensor is going to be since you're regularly going to see positive pressure from the turbo, but this is something they tell us in electronics to be a big no-no.


-Ted

 

As far as I understood it. Even with boost, the non-turbo pressure sensor will consistently read 0. Not that boost will kill it, it just won't affect it. Therefore at 0 on the pressure sensor, chances are I'm boosting, or just about to.

 

You're right.
That's why I said "clamp".
But these things are not meant to be banging positive boost on, so I question how much can the pressure sensor take before it just pukes?
This is basic electronics.
You're running the electronic sensor (it's a pressure transducer) outside of it's normal operating parameters, and this is a big no-no.


-Ted

 

What would be my other options? What kind of signal would a TII pressure sensor send to my NA computer? People have done these swaps on NA puters, so wht's the work-around?

 

I ran mine for about 20k miles and it still checked out just fine on a DMM and a mityvac. Though, I went with TII electronics after that just for the sake of reliability and ease of starting/etc, then i went to a microtech.

 

Will the SAFC be able to lean out the idle or does the NA computer ignore the MAF signals and etc at idle?

I'm gonna take a search around and see how much of a pain in the *** it is to switch in a TII ECU on the NA harness. I really didn't want to move over to TII electronics.

 

Yes, it will.

 

why not run an Rtek 2.0 ?

 

Doing this on a very tight budget. At my current rate, this project will be done for just under $500. An Rtek will just toss my *** right over that haha.

 

Cheap will bite you in the ***.

There is a way to use the S4 turbo ECU and the S4 turbo boost sensor with your NA harness.
ebay has these things for under $100 for both if you look.


-Ted