normal 02 chart readings? could use advice

[djamesp]

Getting weird variations in AFR with everything off, should be running entirely off the VE table, but dropping it into drive while stopped sometimes gives me a ridiculously lean reading, wideband + factory o2s and its obviously chugging a little. Smooths out and lands right around 14.1 where I want it to as soon as i hit the throttle (most of the time, sometimes it stays 17-18). Putting it back in park drops it to 10-11. After driving around town yesterday trying to come up with some data i see the o2s are way choppy at higher throttle, in the log between 2-3min is the best example of what Im talking about.

If someone would take a look at what i have going here id appreciate it. obvioulsy pretty new to the tuning part of this {0} could probably use a full once over by someone who does know what theyre doing, itd be helpful to know im headed in the right direction anyway. Truck is a 2005 silverado rwd 4.8 w/7875 + deka 80s + 4L80e.

Thanks!!



23-04-14 19-37-03.hpl05 silv 80lb 7875 04-15-23.hpt

[5FDP]

I can't view the log but something does seems off.

Like for example with power enrichment, it would be commanding an air fuel ratio in the 13's under boost and your VE table has some massive values in it. Both of those things are wrong. Not sure if you did those changes or the person before you did.

What is your fuel system setup like. Return, returnless?

What fuel pressure are you running?

What MAP sensor is that? I don't know those linear and offset settings.

[djamesp]

Here's a different log, same issue. Return system, 58psi w/vacuum referenced regulator, MAP sensor was questionable (at least I'd never heard of em) but bench test was pretty damn close to the data they provided: https://speedmaxinnovation.com/produ...m4-lm7-l59-lr4
On the VE table, are you talking about the >110kpa rows? I haven't really made it into boost to tweak anything, those are mostly the initial multiply-by-whatever values to get the thing running. I was under the impression I was shooting for around 12.5-13 at the top end of PE/BE, that's not correct?

Much appreciated, nothing curbs enthusiasm like having no idea what to do lol

23-04-14 19-37-03.hpl

[5FDP]

A naturally aspirated engine would be fine with 12.5-13.0 AFR but a pump gas engine with boost is likely to grenade pistons doing that.

You want to target around 11.0-11.5 AFR with boost. E85 fuel will let you run leaner in the low 12's.

[djamesp]

Yikes, glad I asked. I haven't found the right words to google this, but when Im targeting these values am i gradually ramping in until peak boost or should I be looking for that target value as soon as its seeing positive pressure? if that makes sense. And you mentioned the VE tables being way off normal, was it just the boost area or?

[blindsquirrel]

Your injector data is not set up for a referenced regulator, these tables need the 0 kPa columns all the way across (all columns the same from left to right).

screenshot.16-04-2023 02.33.51.png

[djamesp]

ah yup that makes sense. changed x2 tables and see when i can give it another go. Thanks!