Thread: Neo tuning question (N/A)

Heya, finally got around to doing some runs and adjustments on my N/A 05 via neo.

I was curious about what ranges other people who run a neo/safc on a n/a spec are lookin at? I've got my low throttle point set to about 20% and the adjustments from -2% to -5% up top, to save a bit of gas dd.

I have the upper throttle point at 50% and the adjustments at -5% down low and -11% up top. Nothing significant but, assuming im doing my math right, it should put me at around 13-14 afr up top.

Do these adjustments look right to the other N/A people? I was curious because while i was on a run, i was watching my afr and at the mid throttle point ~35% the afr would hover around 15-16 or so, which kinda startled me a bit, it seemed really high.

Is this normal, should i reduce the adjustments up top, throttle points, or something else? I got some logs recorded but its just afr vs time. I didnt get the run but i did a quick drive home on the freeway and caught a short recording of that. I can post up if needed.

What are your afr's at WOT? You can't go off what other people use for corrections, as every car is different. When you are in closed loop (ie. idle and cruising rpm's) you will always be around 14.7 afr, so don't worry about being "lean" in those conditions.

Also, adjusting low throttle will have zero effect on gas mileage, etc. The only reason to tune low throttle is to zero out short term fuel trims to avoid tune drift.

Originally Posted by MisterNuts

What are your afr's at WOT? You can't go off what other people use for corrections, as every car is different. When you are in closed loop (ie. idle and cruising rpm's) you will always be around 14.7 afr, so don't worry about being "lean" in those conditions.

Also, adjusting low throttle will have zero effect on gas mileage, etc. The only reason to tune low throttle is to zero out short term fuel trims to avoid tune drift.

Yeah, im aware of the differences, i was just curious as to how significant other people's changes were. At WOT before adjustments the afr was between 13 and 11. I didnt accurately record after adjustments however, but i think they hovered around 12.5 or so.

So I should just clear out the low throttle points and only leave the high ones then? I was reading a forum post elsewhere and it was explaining how to do low throttle, so i figured i would do it as well.

If you have an OBDII scanner that reads short term fuel trims, then you can adjust low throttle settings by following that how-to.

N/A, I had about -3% to -5% from 3k-5k, and then went up to -9% closer to redline.

low throttle tuning will not affect anything (gas mileage or otherwise) on an afc. reason being is the ecu runs in closed loop until a certain rpm, so even changes you make to the low throttle points will make no difference unless you unplug the primary o2, which will cause a whole new host of problems.

like karl said, you can't go by others adjustments. to me, your values seem low (example, boosted, my corrections were only -8 thru -11. n/a they were much higher in the 11-15 range iirc). also, don't bother trying to tune high throttle below 2800rpms, as this is also part of closed loop and you will be scratching your head as to why no changes are being made to your afr's.

i'd set your tip in value lower then that. if your values are correct and you see a nice linear degradation in afr's, you should be able to get by with 35% or lower (just a little above quarter throttle).

if you have a log that bases afr vs rpm, maybe we can help you out a little more with your tune.

Sadly I don't have vs rpm cuz I don't have an ssi4 but I got a basic idea of where the points are. I think I'm about close to where I needs to be, but I didn't realize it was a closed loop til 2800rpm, so I guess I can re adjust the scale and make it a bit more accurate.

Originally Posted by Hardstyle

Sadly I don't have vs rpm cuz I don't have an ssi4 but I got a basic idea of where the points are. I think I'm about close to where I needs to be, but I didn't realize it was a closed loop til 2800rpm, so I guess I can re adjust the scale and make it a bit more accurate.

Realistically, you really don't need that many correction points. But if you aren't tuning low throttle at all, might as well.

yeah, the ecu can interpolate quite a bit between rpm ranges, and the neo has something crazy like 22 correction points or something. i think 10-12 would be more than enough, i mean we only rev out to 6200 :P

well ive been doing a few pulls with the adjustments i have now (which sit around 7-9% below 5k rpm and 9-12% above) and watching my gauge it tends to hover around 13.5-13.9 % in the first couple thousand and 12.5ish still over 5.5k, so i needa add a percent from the first and subtract a few from the last, so i think im getting close to where i need to be, 13.5ish is the target number, correct? i think i needa up the higher end to 15%, which i was hesitant to do because of the secondaries opening, i assumed there would have been a higher afr at this point, but i guess it drastically adds more fuel when they open?

I removed the low throttle adjustments and set the points to 15% and 35%.

Shoot for no more than 13:1. I've seen a few cars make more power around 12.6-12.8:1 so don't think leaner is better necessarily.

im not sure on these but i've only tuned with boost but, i thought with factory pistons no more that 12.0 and with forged 12.8 was as far as you wanted to go? wont to know why 13.1 or 12.8 with a factory piston is ok? this would be helpful to me so i know more about what the qr25de likes and is capable of handling without the risk of loosing a safe dd to haul kids in everyday.

Pistons don't really matter, you'll have to run a lot leaner than 13:1 to cause detonation that would damage your ringlands.

it's not so much as dangerous on the qr, but dangerous on any engine.

low/mid 11's to low 12's is considered 'okay' for most FI applications, given everything else is dialed in (fueling, timing, and your engine isn't shitting the bed previously). where you make the most power is the grey area. some people make more power in low 11's. some people make more power in the higher 11's. my buddy made more power by going richer (11.2, then petered down to 10.8 at 5600rpms to redline). but you'll never know until you put the car on the dyno.

you can run higher air/fuels with better fuel (e85 or methanol injection) but the car will only run as good as the tune. just because you can tune for 11.0 or 12.8, doesn't mean you'll make more power here or there, or that your motor will live very long either. that's just for explanation purposes.