talked to split second about their afc with NA Tuning!!!!

Wouldn't you want to tune a little leaner for N/A, like 14:1 or so? Sorry, I'm a n00b to N/A tuning.
 
Wouldn't you want to tune a little leaner for N/A, like 14:1 or so? Sorry, I'm a n00b to N/A tuning.

12.5 to 12.8:1 for power still.

NA, just like FI, can be tuned to run VERY lean for lean cruise settings (high 14's).... but under heavy load, it still wants to be down around the mid 12's....
 
12.5 to 12.8:1 for power still.

NA, just like FI, can be tuned to run VERY lean for lean cruise settings (high 14's).... but under heavy load, it still wants to be down around the mid 12's....
Makes sense - same motor right? I guess the only difference is that us F/I guys have to take timing retardation in account?
 
Makes sense - same motor right? I guess the only difference is that us F/I guys have to take timing retardation in account?

Its the same for just about ANY piston motor... 12.5 to 12.8 at 0"hg.... then richening up from there as you get into positive pressure territory.

even on an NA car, you retard timing as you approach maximum load....its just you don't need to be as aggressive with it because you stop at 0"hg....
 
niky, have you tried simply using a relay to disconect the O2S and force it open loop whenever you want? eg 50% TPS. Works for my OBD1 Australian car. Never had a CEL.

I could do that. The Unichip has separate controls that can trigger an event based on RPM (used for nitrous, 5th injector and other neat stuff)... I'm waiting for my tuner to come home... he's out in the provinces right now acting as technical director for a fuel-economy challenge... nice tip! Thanks!
 
Very interested in this. Is there a chance the ecu will eventually learn around this, cause I remember reading that in a few places? Time for me to do some serious research on this :).
 
There is no ECU learning in open loop, correct? Only in closed loop is there a potential for ECU learning. And he only tuned for open loop, correct?
 
Very interested in this. Is there a chance the ecu will eventually learn around this, cause I remember reading that in a few places? Time for me to do some serious research on this :).

it does not learn around it on the msp so i do not forsee it doing so here. if after three or four drive cycles the tune sticks i would not worry about it.
 
Yeah, it only tunes the open loop 100%, the closed loop could be tuned, but the computer compensates over the tune and basically cancels it out.

From what I've gathered open loop runs at Wide open throttle, from about 4,000 up.....Closed loop takes over during deceleration and under cruising/light acceleration, and under 4,000rpms...

My question would be if a voltage clamp would allow you to run constant open????

There is no ECU learning in open loop, correct? Only in closed loop is there a potential for ECU learning. And he only tuned for open loop, correct?
 
That's what Sleepy is talking about... dummying the O2 sensor at low rpms should have that effect... I talked to the tuner, and he says that he's been thinking of doing that.

My car, when we fully map it from 0-6500 rpms, runs fine for the first week or two, then starts acting funny at low rpms, and eventually needs to be reset. By not touching the closed loop area, it seems there's nothing to upset the ECU, so it doesn't try to learn around the programmed changes anymore.

According to the dyno and road experience, the area where the stock ECU is the most annoying is between idle and 3000 rpm at low-to-medium throttle and on deceleration, where my car used to pop and fizz like a race car.

I'm still going to try the O2 defeat, cause the car feels so much stronger at low rpms when it's tuned... I gained about 5-10 hp at 3000 rpm with my previous mapping, and removing that mapping makes for a really noticeable loss in power at low rpms... which just makes the kick when the Unichip kicks in over 3600 rpms even more noticeable... and entertaining... :D
 
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Have there been any dynos done with the SS AFC on a NA car? If this would make 5-10 whp as niky says it would be awesome. I don't think there is anything else for NA that give that much hp for the money. Is there anyone else using the SS except for jamesk? This is looking very promising. If everything seems ok for a couple of weeks I am pretty sure I will be getting this.
 
yea i tried to dump more fuel into closed loop but the ecu leans its way around it, so when open loop happens, my map starts taking place, but that is where the gain is anyway.

the splitsecond afc does not have that feature where you can switch to closed to open loop when you want.

i know it seems stupid to tune 4000 to 6500 rpms, but when your in a 1/4 mile, thats the rpm range people will be in, and like i said, i now have perfect afr!
 
A disclaimer... I have a 2nd gen Unichip, not an AFC... so my gains are from both fuel and ignition... but we've seen a good gain, probably 5-8 from just fuel... but the gains peter out near redline (stupid valvetrain... &%$&^*)... Yeah, 4-6k is where it's at in the quarter mile, but remember, 1st-2nd drops you to 3600 rpm or so, so you want all the help you can get in the midrange.
 
A disclaimer... I have a 2nd gen Unichip, not an AFC... so my gains are from both fuel and ignition... but we've seen a good gain, probably 5-8 from just fuel... but the gains peter out near redline (stupid valvetrain... &%$&^*)... Yeah, 4-6k is where it's at in the quarter mile, but remember, 1st-2nd drops you to 3600 rpm or so, so you want all the help you can get in the midrange.
So, 2nd gen unichip will do fuel & timing? As in advancing not just retarding? NA will need advance on timing. And it holds the tune & oem ecu doesn't screw with it? Sorry, researching. I want afc + timing(adv) piggyback that'll not be jacked with all the time by the oem ecu.
 
I'm running OBDI, but yes, it does it... unfortunately, while we see nice little bumps on the dyno from advancing, the tuner says the car doesn't react to advance like he'd expect (meaning, the ECU may still be screwing with us)... and yes, the stock ECU does its best to screw up the settings after about a week or so of driving...

I'm currently testing a "no-tuning before 3600 rpm" set-up to see if that changes it. Will update you guys once I've got my new headers and clutch in, and do a final re-tune.
 
I'm currently testing a "no-tuning before 3600 rpm" set-up to see if that changes it. Will update you guys once I've got my new headers and clutch in, and do a final re-tune.

I'm assuming that's the OPEN LOOP/CLOSED LOOP switch over. But please confirm that depending on the throttle position, you may or may not actually cross over into OPEN LOOP.
 
my car switches sometimes 4000 rpms and other times 5000 rpms, but im hoping that it has to do with my exhaust leak
 

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