eb02z06

iTrader: (18)

Guys-I can't figure this out. My car is pulling all timing on the launch or when trying to do a burnout. Basically if i put my foot on the brake and the gas the car falls flat on it's face, same if i just hit it. But it doesn't do it all the time it's weird. Can someone look at my log and my scan? I'm pulling my hair out. And one other thing-my LTFTm's are going positive for some reason-i just changed the 02's as well. If you look at my IFR table it's on a 75lb swing-and this is for 96lb injectors-something weird is going on?

Frost

iTrader: (45)

for trims: Your VE and MAF table are both stock, not sure why your IFR is so much lower than actual.... what is your fuel pressure?

For spark loss: log knock learn and check out the timing modifier vs. IAT.

Also, your TPS NEVER shows below 5% at idle and averages about 8% at idle...

edcmat-l1

iTrader: (10)

Cant view it from this computer, but WTF is up with that? No wonder its a dog.
How can you be running stock MAFand VE tables with a set up radical enough to require 96 lbs injectors?
IMO, that setup should open loop SD. LTFT turned off at the minimum.

eb02z06

iTrader: (18)

Come on-car can't be a dog, 9.67@145.88 mph? VE is increased by 5% and so is the MAF. Fuel pressure is set to 44 psi. I did a VE, MAF tune but then the fuel trims went +25, so i put it back to stock and just increased the VE and MAF by 5%.

Last time out-there was no issue-I was getting 1.47 shorts leaving off idle.

I know, i know everyone keeps hastling me on the MAF-it's crude and simpl and it works. Beleive me I want to ditch it but I don't want to go from one set of troubles to another.

edcmat-l1

iTrader: (10)

Well obviously its not a dog. But, the VE and maf being off will damn sure make it feel "flat".
I've done cars that made great power but just felt soft. They all had one thing in common. VE was way off. MAF adjustment ONLY to correct fueling.
Sorry, didnt mean to call your 9 second car a dog.

eb02z06

iTrader: (18)

No problem bro-it doesn't feel flat-something is goin on with TM or burst knock or something-if you look at the log timing goes from 29 degrees to -3.5 as soon as the TPS goes to 100% and the car goes pig rich, timing then doesn't come back until 4800 rpm.

Frost

iTrader: (45)

Your burst knock is zero'd out, log your knock-learn factor and possibly some other modifiers...

BUT

your IATs in your log start at 124F and then drop from what must be meth, but look at your IAT spark modifier at 124F... it's between the 2 columns that I circled and under boost you will sit at the bottom of this table until the meth settles in.

eb02z06

iTrader: (18)

Good find bro! I did that to save the motor incase the meth failed with my stock motor-those tables are actualy higher than stock-should i turn thm down or just reduce them. Weird-it was hooter last time out and none of this happened-not sure why my IAT's where hotter this time out?

Frost

iTrader: (45)

Just wipe it out in the bottom few cells that you are actually in (going by cyl fill) at WOT and you will retain part-throttle usage if you know this to be safe. FWIW I run a lot of boost too on pump and meth(16.5ish PSI), and I purge/test my pump before I get into WOT everytime I do it. This isn't what I'd generally tell people to do, but you know what you are getting into and what you are trying to accomplish.

Log you knock learn factor also.

eb02z06

iTrader: (18)

Hey bro-are you SD or still MAF?

Frost

iTrader: (45)

back and forth somewhat... I use my car to test some odd things that I wouldn't do to other folks cars Right now I am back on a MAF tune ( I know, *gasp* a turbo and 16 psi on pump and a MAF). I am working on a long term experiment related to drivability right now. 2/3 bar is much more accurate and lets me run the fueling closer to the edge where it makes more power, but you would be suprised what a MAF tune can do...

eb02z06

iTrader: (18)

That's the only reason I'm still MAF-it's working BUT I'm questioning a few things but I'm not 100% sure i can blame the MAF. Since going to the 96's my fuel trims keep going out of wack. I'll fire the car up and she'll run fine and idle at 14.7 AFR-then all of a sudden the aFr will go to 18.1 and the car will die. I was getting o2 switching codes so I replaced them and it's still doing it. I was 75lb swing on my IFR tables but the LTFTm's are still show positive values-first pass the trims locked at +7 and my AFR was 11.1 acorss the board-next pull they went to +4 and the AFR went to 12.5. So I don't know if this is because of the rims, MAF or maybe the meth didn't flow as much or maybe the pumps didn't flow as much-it's hard to watch the FP guage so I have to start logging it. I may just go back to 60's if I can sort out these 96's. Or maybe all it needs is complete VE tune in 3 bar? I don't see how the ve tune maf calibration can help much when boost-it's all going to be dependent on my right foot?

Frost

iTrader: (45)

If your meth is alkycontrol (or ECS) it should be dead-on repeatable unless there is a mechanical problem or it is not referenced properly to the manifold.

You didn't log any MAF functions so I can't see where it runs out, but with your setup it sounds like it peaks out between 4200-5K... from there, you can do nothing but add to the PE table. Once thinga are this far out of the window don't look for the added trim percentage to be anything real (or at least calculable).

While running a MAF tune (even though my turbo buries it EARLY in high gears) fueling will change quite a bit with the weather. Running past MAF limits without a 2/3bar OS is MUCH MUCH easier on a supercharged setup than it is on a turbo. I have to keep my motor FAT on a MAF tune whereas like I mentioned, fuel can be much more tightly controlled with a custom OS.

With the money you have in your setup why not just pony up and get an HPT 2/3 tune done? You could always drop it off with a pro (don't know your level of tuning experience) and keep your software to tinker/make changes from there...

How much boost are you running? what is your boost curve like (how much are you making early on?)

highpockets

iTrader: (22)

I will be watching your progress on this issue. I have a very similar,more severe problem. Car is pulling timing at about 50% tps or when transitioning to PE mode,MAF is pegged,just starting to build boost 1-2.5 psi,severely falls down. Brand new twin turbo 402,car is OK below 50% or out of boost but will NOT turn 5000 rpms,downhill with a tailwind !No boost leaks,wastegates OK,plenty of fuel,fairly conservative timing.Did have a knock issue(seemed to be related to the LS2 sensors I installed) swapped back to the original,still falling down.Very bad,can outrun it with my stock 05 C6 auto ! Not rying to hijack,just wondering if I have a similar issue ?

Frost

iTrader: (45)

Your MAF is not pegged or close... Your timing is very (too) high under load and you get KR as a result, good thing it's not actually making boost. Looking at your MAP sensor, there is only like 1 place where it moves north of 100kpa (into boost) and twins should be wayyy into boost by 3500 and 50% throttle unless they are GIANTS. Your MAP sensor says you are not making boost.

eb02z06

iTrader: (18)

Bro-the MAF is maxing out at 4800 rpm, boost peeks around 18.5 at 6900-guage is showing 20.

I think I found another area where my timing retard might be linked to. Uner Engine=>Torque Mangement=>Abuse=>Drivetrain Abuse my rpm setting is 2000 and my mph setting is 255, I think If I raise them to 8000 and lower mph to 0 it might help?

No one around here to do the 3 bar-I'm going to just have to do it myself with some help from guys like yourself .

If I had EFIlive then I could get Slowhawk to get me started.

I'll be sending you a pm bro-thanks for all the help!