Quick SAFC2 question

[95redturboawd]

I've been doing a bunch of reading about tuning with the SAFC2 and I'm confused on something. I have 550 injectors so I should start by taking away -15% at all rpm points. But when I look at the sample car on RRE: RRE's Super AFC Setting and Adjustment Tips

I pasted it here for convenience. I have pretty much the same mods, and I know that no two cars are the same, but none of those corrections are anywhere close to -15%! Can this just be chalked up to our cars not being the same?

2G Turbo

16G Turbo, RSR Cat Back, RSR DP-no cat, Filter, 17psi, Front Mount I/C, Denso in tank pump, 550cc Injectors, Side and Lower honeycombs out, Adjusting screw backed out flush
Low Setting:
1K +39 2K +13 3K + 6 4K +3 5K +3 5.5K + 3 6K +3 7K +3
High Setting:
1K -10 2K -10 3K -10 4K -10 5K -3 5.5K +6 6K +8 7K +8
TH-Point
Lo 30% Hi 80%

 

[turbolarry]

Having the honeycombs out makes a big difference in AFC settings, which is why RRE's is so different. Have you modded your MAF/removed your honeycombs?

 

[95redturboawd]

No the maf is untouched. I guess that makes sense. But now I have another question, one guide I'm reading says to tune with the fuel trims, and one says to tune with the o2 voltage.

 

[sexystover]

i tune my SAFC using my wideband, im running 660s with a gm maf and maft and i have to pull 38ish% fuel at WOT on a big 16g on 21psi, i believe its because my AFPR raises the fuel pressure 1 psi for every 1 psi of boost so it practically compensates for itself

i just aim for a 11.0-11.5:1 afr

 

[turbolarry]

No the maf is untouched. I guess that makes sense. But now I have another question, one guide I'm reading says to tune with the fuel trims, and one says to tune with the o2 voltage.

You monitor the fuel trims for idle and part throttle cruising.
The O2 voltage is used for WOT tuning, but it's not precise and only gets you in the ballpark of rich and lean. A wideband should really be used.

 

[knochgoon24]

Did you look at the one right below that? The one that had the honeycomb untouched?

Big 16 G Turbo, Apex Cat Back, RRE DP-3" Cat, Filter, 19psi, Front Mount I/C, Walbro 255 HP in tank pump, 550cc Injectors, honeycombs all in, Adjusting screw left alone, Big GReddy FMIC

Low Setting:
1K +-2 2K -4 3K -6 4K -10 5K -10 5.5K -10 6K -10 7K -10
High Setting:
1K -21 2K -23 3K -24 4K -23 5K -22 5.5K -22 6K -21 7K -18
TH-Point
Lo 30% Hi 80%

If you average the high and low settings together, there's your ~15%.

 

[spyderturbo007]

I would recommend putting the honeycombs back in and starting again. It's going to make your life much easier.

 

[95redturboawd]

I haven't touched the maf, the honeycombs are in it. And I do have a wideband. Are you looking for the wideband to read as close to 14.7 as possible at idle and part throttle? Then 11-11.5 at WOT?

 

[sexystover]

the way i tuned it was tune for idle, then cruise at your "specified low throttle percent" in my case its 30 percent, so i drive at 30 percent and adjust till im in the 14.7 area (it will never stay dead on since your in closed loop) , then tune your high percent fuel trim doing a wot pull

 

[spyderturbo007]

I haven't touched the maf, the honeycombs are in it. And I do have a wideband. Are you looking for the wideband to read as close to 14.7 as possible at idle and part throttle? Then 11-11.5 at WOT?

Ah, crap. Sorry about that. I just glanced at your first post and assumed the settings / mods you had posted were yours.

Do you have a logger? To answer your question, yes, you want around 14.7:1 when in closed loop and ~11:1 when in open loop. The closed loop AFR is consistent across all cars, but open loop varies from vehicle to vehicle.

Some people might run just find at 11:1 and other vehicles might be seeing 12 counts of knock. This is where the logger comes into play.

 

[95redturboawd]

I've since switched to a 14b for reasons I don't care to go into, and I'm noticing that as I look at the wideband when I'm in high throttle (80%) the number isn't bouncing around like it does when I'm in low throttle. It's still in closed loop at that point correct?

Also the wideband has been reading 10.0 at full spool (so who knows that it's actually reading) even though I've removed 50% fuel throughout that rpm band on the safc, and that's at 80% throttle, not even WOT.

 

[95redturboawd]

Sorry to bump, but I'm hoping someone can chime in on my problem and I tried PMing both spyderturbo and knochgoon, neither worked.