Ok guys, here are the logs from my first data logging session.

I will give you 2nd and 3rd gear pulls for simplicity.

2nd gear:

Began at 4875 rpm ended at 7250rpm
Began with 0 knock, 9 counts beginning at 5968 rpm and plateau at 12 counts till 7250rpm
Timing began 20 deg dropped to 15 degrees at 7250
O2 began at .76 volts and peaked at .86 volts
Injector pulse began at 15.64ms and ended at 16.92ms
Air temp began at 107deg and ended at 104deg
Coolant temp constant 189deg
O2 trim constant at 99%


3rd gear:

Began at 4812 rpm ended at 6687rpm
Began with 0 knock, 14 counts at 5593 and plateau at 27 counts till 6687rpm
Timing began 20 deg dropped to 10 degrees at 6687
O2 began at .90 volts and dropped to .71 volts at 6687rpm
Injector pulse began at 15.64ms and ended at 18.71ms
Air temp began at 103deg and ended at 97deg
Coolant temp constant 189deg
O2 trim constant at 99%


So why am I getting knock? Am I running out of fuel? I need help. Am I doing damage to my new engine?

 

what are you logging with, what is the whole set up? is it the 92 laser in your sig, with aem ems?


[Modified by racerxadam, 8:09 PM 2/11/2003]

 

Pocket Logger PDA.

No electronics yet. Stock boost with stock fuel. Boost creeps to 14psi.

 

Anybody?

 

Your ECU is pulling timing to eliminate knock. I don't know how much it can pull, sounds like 10 to 15 deg or so

Your ECU won't adjust the A/F when running under full throttle. It reads straight off the map. You are running rich, but without a WIDEBAND O2, you have basicaly no idea how rich.

In any event, it sounds like the ECU is trying is't dardest to pull timing... not a good way to run. Is there any mod you can do to take out some timing (base time, electric box) ?


[edit-can't typr]


[Modified by hybridsol, 11:51 PM 2/11/2003]

 

sounds like your running out of fuel. .71 is way too lean, (if your o2 is reading properly) generally a 1G likes to run in the .88 range on pump. I wouldn't recommend counting on the stock 02 for serious tuning though anyway. Follow knock more so than the 02 when tuning on pump gas. At the stock 12-14psi you really shoudln't be running out of fuel. 18ms looks really high for 7k i'm willing to bet your running 100%duty. I would look into the fuel system for problems, check the FPR(make sure it rises 1:1 with boost), pump, filter ect.


[Modified by heavyGSX, 12:06 AM 2/12/2003]

 

So you're saying I am running rich when the knock is present. How and where do you see this? Is that what the O2 reading is saying?

And I have the base timing set at the standard 5deg BTDC at idle. But I guess maybe with the higher compression I should retard the base timing some. I am running 93 octane and last week ran 3 gal of 93 with a gallon of Xylene. Thats an octane of about 98.5 and I must say, it ran it's *** off in 3rd. Obviously it didn't have to retard the timing as much.

 

Stock fuel pump, stock injectors (450cc), stock EVERYTHING when it comes to fuel.

So you're saying I am running lean @ redline? Ok, makes sense. That's what I was thinking it might be. I am running stock boost (11psi) but it creeps to 14psi in 3rd near redline. Stock fuel system with 14b is SUPPOSED to be good to 18psi. So that shouldn't be on the raged edge. But the increased compression I have may be throwing it off?

 

War_hammer- is the volt range different on these O2 sensors? I thought 0.5VDC was 14.7, and the higher the volt, the richer the mixture? Thanks- just trying to learn.

 

I don't know. Maybe on a Honda. I don't know if that would hold true on DSM's. That's why I am asking.

 

Just found out that target O2 voltage under WOT is .92-.94

So I am definitely running lean. Hmmm. Need at the least a FPR I guess and then a pump.

 

look in to either the fuel pressure regulator or the fuel filter. The regulators like to go up when they get old on the 1Gs. It's pretty obvious it's lean. high MS count along with the 02 reading lean, followed by knock. As far as your compression, BSFC lowers when you raise compression, therefore it uses less fuel to make a given amount of HP, so at 14psi at a higher compression the fuel system should be flowing the same amount as before or if anything, less at the same boost level.


[Modified by heavyGSX, 1:11 AM 2/12/2003]

 

.92.94 is the 2G target A/F...1Gs tend to give a lower voltage

 

So how low is low? I take it that .71 at redline is way too low.

 

yeah, .71 is too low. a stock narrow band 02 only really reads accurately at 14.7:1 a/f which is .5v. anything above that is richer and below is leaner. On a turbo application you want to run about 11.8:1 to 12:2 depending on fuel/timing ect so you'd want to be in the upper voltage ranges. .84 is about as low as i would go on pump gas. Really, watch knock more so than worry about the voltage. Use the voltage as a genral idea of which direction to go. I would richen it up, which in your case i bet it won't go much richer since it looks to be near max duty cylce.

 

What is max duty cycle on the 450's and other than installing a FPR or a SAFC or a pump, how can I get more fuel in there?

 

It sounds to me that you might be running a little lean up top. The taller the gear, the more strain on the motor. I would suggest a walboro high pressure intank in that bad boy. Knowing a little about dsm's most users upgrade the pump as soon as they get the car.
EVIL