ve tune setup help

[eagle1flcl]

ok guys I have a 2000 chevy Tahoe z71 (obs) truck runs and drives on stock tune but engine is not stock the build is a 385 stroker with crane cams 282h grind (duration at 50* 226*in / 226*ex106 lsa) intake is sdpc vortec tpi lower unit with stock tpi upper intake /runners / throttle body /injectors with the stock tune it runs pretty good has good low end tq and power but my ltfts and stfts are -30 between .800 rpm to .2800 I have been logging with the maf unplugged my runs are warmed up driving for 35/40 miles mostly highway so 50-75 mph slowly getting up to speed never going over 25% throttle I just need some help finding a good ve write up for the older ecu because I am not interested in the 411 pcm swap I know it opens up more parameters but I can live with what I have any help would be great and yes this is a custom build the stock intake was the junk spider injection and I wanted more low end tq for this truck anyhow but none the less I just need a good idea on how to set up my tune and hardware to tune the older ve table its not like the ls setups

[5FDP]

Even with the older computer you should still be able to create a AFR or Lambda error using a wideband to correct the VE table and MAF.

To me it's pointless to even try using fuel trims on a setup like this, a wideband is a must here.

What I don't know is what version of the software you have to setting up the wideband. If you have the PRO interface it will be easy, the standard interface will require you to wire the wideband in through a 5v circuit to the computer. Most like to use the EGR circuit. There are several write ups out there for setting up the wideband through the EGR as well as setting up the graphs to log the error.

[eagle1flcl]

well I do have the pro version and I plan to buy a wideband around tax time wife is peved with the money ive already put into my build but I figured for now if I can get it closer than it is then I will be happy with it the truck runs nice and has power but I know the tune isent right and its my dd it is defintly a gas hog but what can you expect with a stroker I drive my charger in the summer and this in the winter oh and it also has full true dual exhaust with headers no cats just straight pipe to mufflers then out the back with both front o2s brand new and on the end of the headers just before the collectors forgot to write that before

[eagle1flcl]

any good recommendations for wideband

[cobaltssoverbooster]

the wideband becomes an issue because there are no trims to calculate fueling errors when in enrichment mode. when the setup experiences a drastic mechanical change from stock then the wideband becomes critical because the enrichment zone will request fuel at a much different rate than stock.
the only way to tune with O2 sensors is to make a histogram with stft+ltft error reporting. you add a new channel called equivalence ratio commanded and add a filter to the histogram that references this channel. to finish the filter you say [eq ratio commanded]=1
this will eliminate any fueling events from your histogram that pertain to enrichment mode or deceleration modes. its crude compared to a wideband so the faster you get one the sooner you can start fixing the conditions that ruin mechanical longevity.

Most common sensors
AEM EUGO 30-0334 $220 (summit racing one is identical SUM-G2997 $200)
Innovate MTXL 3918 $198
Innovate LM-2 $350-$480
Dayton Sensors WEGO III 112002 $438

[eagle1flcl]

well I have pe disabled right now and I have a pid for stft+ltft that I am logging and seeing but im trying to adjust the ve table between 800 rpm to apout 2800 rpm when I drive and log with the stock tune and pe still enabled it dosent bog or have any wot trouble it gets up and goes when im wot with enough power to get out of its own way I just know that when im cruseing say around 1800 rpm at 65 its running rich

[eagle1flcl]

I will take a log tomorrow with pe disabled and post it I am just un sure of what all to disable to tune ve on this ecu

[cobaltssoverbooster]

dont disable pe. commanding stoich in an enrichment situation is the worst thing you could do.

[Ben Charles]

Never understood why tutorials want to disable PE...

[eagle1flcl]

ok I wll leave pe alone any other ideas for now guys thanks for the help so far

[cobaltssoverbooster]

tune what you can on trims and stay out of pe the best you can until the wideband shows up to prevent mechanical failures.

[workingdog]

They only recommend disabling PE when you're trying to dial in the VE table so PE's changing commanded AFR isn't screwing up the trims. It's not intended for long term use.

[eagle1flcl]

yea that's what im trying to do is the ve table between 800 rpm and 4000 rpm total I know that I need a wideband for any real tuneing but I have read different forms that say what to disable and what to scan for but some things aren't on my ecu file so I am looking for a good ve write up for the older ecus

[Ben Charles]

They only recommend disabling PE when you're trying to dial in the VE table so PE's changing commanded AFR isn't screwing up the trims. It's not intended for long term use.

That’s just it... even in that scenario I would still want PE to kick in when it needs too

[IARLLC]

One quick thing!
The upper TPI intake has a major restriction right behind the throttle body. You will gain A LOT of wot airflow and throttle response by porting/matching that inlet to the throttle body gasket. People even upgrade throttle body without porting there and end up with less flow than a stock throttle body with a ported upper manifold....

I only bring this up because I would do it before you get going too much on the tuning. It will make a major difference on your airflow from light throttle all of the way up.

I am sure you know the benefits of better runners but for now porting the upper intake is free...

[eagle1flcl]

thanks for that tip yea I want to get the set from FAST I have read good things about their setup but anyhow so with my log this morning its saying its -30 for the majority of the stfts so should I take that out and see about another run

[cobaltssoverbooster]

They only recommend disabling PE when you're trying to dial in the VE table so PE's changing commanded AFR isn't screwing up the trims. It's not intended for long term use.

That’s just it... even in that scenario I would still want PE to kick in when it needs too

I agree with Ben on it retains a level of mechanical safety that is more desired than running lean and smoking 10k in internals in some cases. If you know how to use the scanner properly and filter the PE sections out then you dont need to disable the PE mode in order to tune the fuel tables. Furthermore, 90% of the people on here dont in car flow test their injectors and have some inherent errors in the flow rate calibration of the injectors. This can lead to offset jumping when PE does kick in. So here you tuned the fuel table with it off and expect it to hit target when its on and it doesn't because the inherent injector flow errors stacked up just enough to cause an offset not equal to the trim system. More of an advanced tuning theory but that initial data will F you every time in some way or another. Even when i do in car flow them i see shift errors, so its not totally perfect.

[eagle1flcl]

well I pe mode to only kick in when im at or above 4500 rpm because I keep the rpm down under 4000 I don't think it is any issue I am just unsure if the other settings I need are right for ve setup

[Ben Charles]

If PE is only kicking in above 4-4500 you have problems

[eagle1flcl]

I set it to kick in at that stock It kicks in lower