Tune Critique please..

[Bayer-Z28]

Been working on this for a while and I think it's pretty much nailed in except for pulling some fuel from WOT still. The car was tuned by some hack back in spring 2011 and I've been working on it since then. -Not in a hurry and it's a fascinating hobby.


Haven't messed with the timing much other than the idle region. Pulled some timing from idle and the IAC seems to work a bit better and it's not as jerky now. Changed some of the Injector EOI events and that seemed to help cold start low throttle drivability a lot (combined with idle spark changes.) Added 8% to the EOI, pulled 6* of timing out of the idle region and tried to smooth the drive and spark tables out. EQ is set to stoich when warmed up. VE table is a little jagged, but that's what the car wants. It could probably use one or two more log runs to dial it in. That was today's only correction after injector timing changes. Also noticing I could use a hair bit more timing around tip-in and lower idle tip-in region. Pulling some timing from the idle region seems to have sacrificed some throttle response.


2000 Camaro, LS1, T56
Wheel2Wheel 243 heads, PatG Torque Cam 224/228/637 .639 110, FAST 102/NW102, No MAF, 42# reflowed stocker injectors, Racetronics 255 pump, return fuel system, 59# fuel pressure. SLP LT's, ORY, Custom TSP Rumbler CatBack, FTP 98mm Lid, TR6 Plugs, 180* stat,

This was just a quick run I made after I pulled some fuel from WOT. Didn't have a whole lot of room to run it. Anyone know how to set up a WOT triggered graph in the scanner for WOT fueling? And don't mind the misnamed Lambda sections in the Table display. I'm afraid to change any of those because they were such a pain to setup for VE calculations.. I Do corrections in Lambda though. Much easier. Was wondering if my O2's were a bit lazy, but they seem to move around fine at 2k rpm. Asked my uncle and he said to hold the car at 2k and see if they move around.

[Bayer-Z28]

Anyone??

[flame]

VE def needs work and WTF with the PE table commanding 13.7? You have 4-7% positive LTFT at WOT.

Your commanded pe ratio and your actual wideband reading should match so you need to dial in the VE table until it does. I can't see your wideband reading as it shows up as unsupported.

[oakley6575]

Your stoich value is wrong unless you are really running pure gasoline. Most gas stations sell E10 these days which has a stoich value of 14.13. Also you said you are running a return style fuel system but your injector data is set up for a returnless system. PE needs to be set to something safe. Like 12.6-13.0. Your idle spark would be better if it blended with the high octane table. That way it transitions from those tables without any bucking/surging. Also I like to turn the CAT lightoff if you aren't running cats. And based on your stft and ltft, you could do some more VE/MAF tuning

[Classic yungsta]

I have a after market harness w/o2's and its says my wide band is unsupported, will prevent me from dialing in open loop pe

[Bayer-Z28]

I've asked the gas station what their stoich value was and they didn't understand me at all.... Which I expected.. So I just set the Stoich value to the local elevation.


And my WOT is still reading rich on WOT.. I'll take another log run this weekend if I can and adjust the VE again after the stocih change.

Your stoich value is wrong unless you are really running pure gasoline. Most gas stations sell E10 these days which has a stoich value of 14.13. Also you said you are running a return style fuel system but your injector data is set up for a returnless system. PE needs to be set to something safe. Like 12.6-13.0. Your idle spark would be better if it blended with the high octane table. That way it transitions from those tables without any bucking/surging. Also I like to turn the CAT lightoff if you aren't running cats. And based on your stft and ltft, you could do some more VE/MAF tuning

And before I mess w the VE again, how does the injector data differ with a return system?? Links??

And I thought all my Cat stuff was off/disabled... Hmmm..
And no MAF yet. I'll mess with that when I get the VE dialed in. Still on SD and have a 100mm MAF sitting in the back seat of the car yet to go in.

[SSUte01]

... Which I expected.. So I just set the Stoich value to the local elevation.

How does atmospheric pressure have any impact on the stoich ratio of a given fuel I assume it's a typo and you meant local average/estimate/other??

[Bayer-Z28]

^ I meant average. I didn't think pump gas was that far off. Never heard much about it.

[flame]

For the couple % diff the stoich point makes its no big deal especially if you aren't sure what the actual ethanol level is. Most of our stuff says up to 10% but is only 3% most of the time.

If you have a vacuum regualtor then you set the flow rate vs kpa to what ever is in the 0 column all the way across. Your pe table should be 1.15 across the board if you want 12.8 a/f then adjust your ve until you get 12.8 on the wideband.

[HoP]

Been working on this for a while and I think it's pretty much nailed in except for pulling some fuel from WOT still. The car was tuned by some hack back in spring 2011 and I've been working on it since then. -Not in a hurry and it's a fascinating hobby.

thanks for a Tuesday laugh

[Bayer-Z28]

^ You're welcome.. I dun had this tuEn compruter from some free chicken so I touut I'd giev it a trai..... My expeereinsess aernt dat uv sum dees fanse peopel that does it forse a livinz... So I just open it and chaneg evryting I caen... I gues I jus got lucky dat it ruens is alll. I thout theze books I bout was written in some french stuff.

For the couple % diff the stoich point makes its no big deal especially if you aren't sure what the actual ethanol level is. Most of our stuff says up to 10% but is only 3% most of the time.

If you have a vacuum regualtor then you set the flow rate vs kpa to what ever is in the 0 column all the way across. Your pe table should be 1.15 across the board if you want 12.8 a/f then adjust your ve until you get 12.8 on the wideband.

It's not vacuum referenced. Any other suggestions I would need to correct this?? I'll look some stuff up and see what I can find too. Tried yesterday but didn't find much.

[Alain2]

42lbs stocker injectors???? Stock from what, a new Corvette ZR1?

Anyway...
Your Injector flow rate is all wrong. Your injectors are probably rated 42lbs at 39 or 43.5 psi, If you run 4 bar injector pressure they become around 49-51 lbs injectors, that is what you need in the setting for your injectors. Wrong injectors data means wrong VE table. You will have to start all over again!

[Bayer-Z28]

^ They're reflowed to 42# Stock injectors from FIC.

And I've asked a couple times for correct injector data, from them and on here and all I've ever gotten was the run around and incomplete data. I've even had reputable and respected tuners tell me to "STFU and bake it into the VE and quit crying about the injector settings." ( )What I have dialed in for the injectors is all I was supplied with. Sometimes it's no wonder why people give up on some stuff.

[flame]

If that is the data then either work with it or throw them in the trash and buy some injectors that come with complete data. If your reg is not vac ref then your flow table is setup right. Set your pe and tune the VE until it matches the wideband

[Russ K]

When the Maf is unplugged (removed in your case), a P0102 code will be set. But the P0102 code is set to no error reported. What Maf code are you getting? I would set P0102 to no mil.

Also your Pe is way too lean, and your IFR table is too low.

Russ Kemp

[Bayer-Z28]

^ The VE may needs a bit more work then. My WB shows 12.5-13 @ WOT...Still rich.

And I'm not getting a MAF code. I'll reset that MIL light and see how it likes it. Not a big deal. I'm relocating soon, so this will have to get placed on hold for a couple weeks until I get the car out there. (3hrs away and ran out of time)

[ssdungeon]

Your stoich value is wrong unless you are really running pure gasoline. Most gas stations sell E10 these days which has a stoich value of 14.13. Also you said you are running a return style fuel system but your injector data is set up for a returnless system. PE needs to be set to something safe. Like 12.6-13.0. Your idle spark would be better if it blended with the high octane table. That way it transitions from those tables without any bucking/surging. Also I like to turn the CAT lightoff if you aren't running cats. And based on your stft and ltft, you could do some more VE/MAF tuning

Im curious to know whats set up differently on returnless vs. return style systems.

[flame]

Im curious to know whats set up differently on returnless vs. return style systems.

It is to do with the regulator. If there is a vacuum referenced regulator then the fuel pressure will increase when vacuum drops so the flow rate at 0kpa is carried across the whole table.