Reposted from Safc Tech

I know this is a lot to ask and I've searched through for almost 2 months scavenging whatever I could.
I want to know the basics of tuning (on an N/A for now).
I just want to know if I should advance or retard my CAS and by how much.
What kind of AFR's should I be aiming for on low and hi throttle when secondaries hit... 13's?
After tuning should I put back the stock sensor to retain closed loop or plug the hole?
Just the essentials and tips please...

Sorry for being a noob and thanks to anyone willing to help

 

A few years ago on stock ECU and SAFC I made 172rwhp on an s4 n/a . I advanced the CAS several degrees and it netted some more HP. However, for some reason the ECU leaned out the mixture when I did that even though I tried richening up the SAFC correction and even installing an FD fuel pump and 550 secondary injectors just to see what would happen. It would run in the high 13's AFR. It never detonated (always ran 87 **** gas) and was rock-solid reliable.

That being said, when I eventually put the timing back to stock it would run pretty rich until I leaned out the SAFC.

You can't tune low and high throttle unless you tap the TPS signal into the pressure sensor. If it is tapped into the stock TPS the low throttle map will be useless. It's kind of pointless anyway to tune low throttle. The stock ECU already runs pretty smooth. Not too many people run open loop on stock ECU. I think the s4 ECU is dumb enough that it wouldn't really do anything (as in, it would only go into open loop and not some failure mode that would prevent it from responding to the SAFC). I personally wouldn't bother with it.

That being said, if you were to try and run open loop you should hook the throttle input to the pressure sensor. Do a search on that, it's common enough.

 

Thank you arghx, I'll add a lil more info about my car:
S5 NA Streetport

Should I advance or retard the timing?
Tune only for Hi throttle and aim for what AFR?

 

if you have an s5 n/a you can hook it right to the TPS. The s5 TPS is full range. And you pretty much need to put it on the dyno and see what the motor likes. You can advance the timing a little, but if you go to far it will lose power (probably won't detonate). Most people would say 13:1 or so for AFR but you have to see how it responds on the dyno.

I honestly don't know why you are bothering with an SAFC on an s5 n/a . You should get an Rtek 2.0 . It's more expensive, but it can control your 6 port and VDI system (like tuning VTEC on a Honda), has built in timing control instead of being ghetto with the crank angle sensor, and doesn't require you to hack up your harness.

If the Rtek was available back in the day I would have never bothered with an SAFC.

 

Actually I've been saving up for the Rtek. So I will go w/ that and throw the Safc.
I wanted to hook up my wideband to the Rtek to log along with rpms and such. Is it easy to tune with?

 

yea the rtek is the way to go sell the s-afc on ebay and get one. If you gotta keep it get on the dyno and get it tuned right (or get a wideband o2 at least)

 

Alright I've already got one but now I just want to know the basics on how to tune... could anyone help?