Somebody examine this log please (DSMlink). How do I fix my knock???

[olmytsi]

I do log lbs/min and i do know at what g/rev i am at as well.

The ecu chooses the map of enrichment based on g/rev and i want to see a breakdown of it, that's all...ie where does 2.75 g/rev put me in terms of the fuel maps.

Yes i am running stock cams and stock intake manifold, just a rebuilt 6 bolt with 2g pistons.

 

[scottsee]

anything over 2.1g/rev is your peak enrichment. Thats covered in the tuning guide...

 

[olmytsi]

Thank you

 

[~laser_craver~]

This is great... I love to see that you guys are willing and able to assist him with his tuning problems.

Is DSMLink and Megatune software relatively similar? Im just curious as to if I will be able to ask for assisntance similar to this when I get my MegaSquirt completely setup. Thanks.

Runt

 

[-DSM2NR-]

I don't have a CAS on my car................how can I adjust base timing?

 

[-DSM2NR-]

Ok, this is weird. I did another run. I decreased the fuel sliders down from -5 to -7. The timing was on -1 from 6000rpm-7500rpm. The A/F ratio was about 10.6:1. The highest knock I got was 3.5 DSMlink indicated that I gained 30hp by decreasing fuel from -5 to -7.

Then, I did another run. This time I decreased fuel from -7 to -9. I didn't touch the timing at all. The A/F ration was reading around 10.8:1. DSMlink indicated that I've lost 35hp and the knock count was actually higher this time. It was at 4.9 WTF.

It seems like the car doesn't like to get leaned out too much. I thought leaning it out will decrease the knock..............so why is it actually getting higher as I approach 11:1 A/F

 

[RavenX]

Ok, this is weird. I did another run. I decreased the fuel sliders down from -5 to -7. The timing was on -1 from 6000rpm-7500rpm. The A/F ratio was about 10.6:1. The highest knock I got was 3.5 DSMlink indicated that I gained 30hp by decreasing fuel from -5 to -7.

Then, I did another run. This time I decreased fuel from -7 to -9. I didn't touch the timing at all. The A/F ration was reading around 10.8:1. DSMlink indicated that I've lost 35hp and the knock count was actually higher this time. It was at 4.9 WTF.

It seems like the car doesn't like to get leaned out too much. I thought leaning it out will decrease the knock..............so why is it actually getting higher as I approach 11:1 A/F

The leaner you go the more power your going to make. However thats not always the case hence why your knocking. Your going to have to make a sacrifice either lean the fuel and lower the timing or riching it up to 10.6-10.8 and up the timing. Its either of the 2 and whichever your car likes is what you should tune around with for your car. You really need to tune for either 0-1 counts of knock. Do not go any higher. Did you do the boost leak test and made sure the knock sensor was torqued properly?

 

[olmytsi]

Where were you knocking (rpm wise)? Post the log if you can

 

[-DSM2NR-]

Can I even check the sensor without pulling the engine? I know it's behind the block (which is difficult to get to).

I'll post the log once I get home. I'm always knocking on the same spot which is 6100rpm+
Everything below has zero counts of knock.

 

[olmytsi]

Can I even check the sensor without pulling the engine? I know it's behind the block (which is difficult to get to).

I'll post the log once I get home. I'm always knocking on the same spot which is 6100rpm+
Everything below has zero counts of knock.

Difficult but not impossible.

 

[mastadogg2]

this guy is not running rich by any means.. i know you cant get accurate readings narrowband but.... 0.92 o2 volts isnt rich at all.. this isnt a 1g. he would want atleast .96-.98 granted his o2 is in good shape.

im going to estimate your running around 19-20psi considering the airflow isnt so great. 32lb/min....... im also guessing your running 650-680 injectors? have you started from scratch and got your fuel trims under control? %0.... low and mid? if your global is off it will greatly increase detonation. i have 680cc myself and run -30%, when i went to -31% i had bad knock.

I would try either pulling some timing where its knocking or richening it up some. if that doesnt help, then turn down the boost and start from the beginning. I got to the point where i can run 25psi+ on 94octane with no sign of knock at all.

Read over this: http://home.comcast.net/~mastadogg/tuning2g.pdf

and btw... dont tune by the "estimated A/F" dsmlink shows.
its what it is an estimate.......

but anyways i got a question, why are you not using your resources and going to dsmlink forums?
thomas & dave will reply directly to your log. if you dont know who they are , they are
responsible for making the great product we call dsmlink

 

[mastadogg2]

also, now that I did read some of the beginning posts. never do pulls and stop at 6200rpm.. do a clean pull to 7k-7.5k

next time your out set your check engine light to turn on @ 2deg knock. or 1deg.
I have mine set to 1deg now but have had it set to 2deg for a very long time.
the more you get used to tuning the easier you will beable to fine tune your car.
if you cant get rid of that knock at all turn the boost down and let someone that
knows what there doing do it.

 

[-DSM2NR-]

The DSMlink came programmed with the injectors I got (FIC 650cc's) so I doubt the global settings are adjusted wrong.

If you check out the other logs you'll notice that I did pull some 7000rpm runs.
I'll post the log that I did yesterday

And where is the DSMlink forum? I tried using the one on dsmlink.com but it won't let me register WTF

 

[olmytsi]

You get a username if you bought a legit copy. If you bought it used, you should contact the seller to get his info so you can e-mail them and get the username "transfered".

 

[-DSM2NR-]

ok thanks

 

[biglady112]

We get all our chips burned for hte injectors we own. We still have to adjust every car. Some a little, some a lot. Every car is different. From a 2G to a 2G. From a 1G to a 1G. Even with the same injectors and even similar mods, every car has to be dialed in. I still don't understand what is so hard. Everyone has given you advice. It takes all of 5 minutes to set a car up.

We installed FIC 950's in a car last week. He had an evo III 16g and a front mount. That was it. We set the fuel pressure and went with it. Car was running 57psi base fuel pressure because the 450's couldn't keep up. He had the car dialed in before it even started.He had to wait just a few minutes after start up for the fuel trims to get lined up. He took it for a drive, came back and adjusted the global 2% and all his trims were within 1% of 0. He is now running 21psi on pump gas(5800ft above sea level), flowing 37lbs/min(2G mas) on a bone stock 7 bolt. Intake/exhuast manifold, cams head and all. Sorry, with the advice given, you need to make adjustments. Don't tune by the seat of your pants. If you dial the injectors in(proper fuel pressure and all) tuning is a breeze.

I tuned a Fp3052 car two weeks ago. Car came to me running horrible. Installed a new throttle body(was literally broken) and started tuning. Got the trims down in about 10-15 minutes. Car went from 27lbs/min to 44lbs/min on pump gas in 4 pulls. car went from lean on the wideband(broken throttle body) to rich. AEM gauge type that only went to 11:1. It ticks up to 11:1 twice during each pull now. It took literally 4 pulls to get the car dialed in after the throttle body. We took 2 or 3 more to raise the boost and check things out. Now he is running 24psi on pump gas.

Steve

 

[-DSM2NR-]

wow, I guess I should take my car to you guys...........

So it takes 5 minutes to set a car up huh? So checking for boost leaks and checking the knock sensor takes up only 5 minutes, hmmmmmmmm.........

So your advice is to mess around with the global settings?
Should I put everything back to zero and go from there? What if I tell you that the car runs 5 degress of knock on zero timing and only 15psi?

I'll go ahead and post my log once I get home and you tell me what to adjust and what not to (since you're an expert), ok? Thanks

I'm not intending to be sarcastic. Sorry if it seems that way

 

[-DSM2NR-]

ok, here's the latest log. Please tell me what to adjust since I'm a n00b at tuning

Some people would say to start out by moving timing to -1 and then adjusting fuel. Others say to move timing to -2 and then adjust fuel. Others say to adjust fuel first and then timing.

So, what should I do Steve?

 

[RavenX]

Bring the timing back down to 0 from 4,000 to 5,000. Go to -2 from 5,500 and up. See if the knock goes away. I not riching it 1-3% from 5,500 and up. Also go to the Miscellaneous options and click on the Fan option so dsmlink makes the radiator fan turn on all the time. Those coolant and intake temps are killing you. It looks like your going to have to fix that before you continue on with the tuning. You generally want to set the timing low and then set the fuel. Once the fuel is set go back to the timing and bring it back up until you start knocking.

 

[-DSM2NR-]

But what about the global fuel setting that Steve is talking about? What should I do with those?
And I don't know what to do about the temps. If I leave the fans on will I have to add or remove timing? Is there any reason why I'm getting high temps? The run was made on a 82 degree night.

And one thing I find interesting with the log is if you notice that when knock increases the timing decreases.

 

[mastadogg2]

man all i gotta do is glance at this log and i can tell your running to lean... why do you keep leaning it out more? try richening it up a bit and see if the knock goes away. if the knock continues then click the global down 1 notch to -30......

I thought you told me you tuned your fuel trims? 12.5% pegged for each one isnt tuned............. I suggest reading the tuning guide and adjusting your deadtime &
global as necessary to reflect your fuel trims and get the car running good. some cars the default settings work , others there off alot. like stated above every car is different.

 

[biglady112]

Alright. Looks half way decent. The knock you are seeing is knock retard. Hence why when knock goes up timing goes down. It is not like the old style loggers for the 1G's that read counts of knock. I would say anything above 3* of retard is actually starting to detonate. At least on pump gas. Try to zero everything out for us. Wouldn't hurt and you could just reload everything. Post a log for us where the car is just idling for about 30-45 seconds. Make sure one more time that your fuel pressure is at 43.5psi base (with the line off and your finger or something plugging the line as you adjust it). Post STFT, selected stft, ltft mid and ltft low in your log. You are to actually tune the car off the STFT. That is what the car is needing for fuel right now(WOT/closed loop). The other 3 will help us with your global and dead time. I bet you are just a few percent +/- on the global and a few u seconds away on the dead time. -If you can get both of the ltft low and mid under 5% and matching or close to it, then that should be close enough to start the tuning again.

Yes the intake temps and coolant temps are affecting you, but its summer and this is the best you can probably do. With the STFT you adjust globally once the other trims are in order. If you are at -5% you add 5% on the global. Once you have the injectors near perfect, then you can use the stft for your wot tuning. This will make sure you have the proper Air/fuel ratio. This part really make a difference.

Have faith. You will get there. You are honestly just a few clicks of a button away.

Steven

 

[mastadogg2]

it doesnt start to detonate at 3deg.. infact 3deg is high and 4deg is dangerous. definitely not recommended to be over 1deg on a satisfied tune.

read this until you understand it, and get your fuel trims under control before posting in this thread again!!!!!
http://home.comcast.net/~mastadogg/tuning2g.pdf

its really not that hard!!!!!! if you havent, take the car out on the highway and cruise at a steady 50mph or so atleast 10-15min
until the trims actually settle. if you recently unhooked your battery, all your link settings would be wiped away. infact i recommend
unhooking the battery so the eprom goes back to original settings, take the car for a nice cruise like i said and then come home and fix your fuel trims. also make sure that the car is indeed going into closed loop by logging a raw value of the idle switch.

 

[mastadogg2]

print this out and use it as a guide to tune your trims and car. I did the dirty work for you and pulled the important information out of the guides for you..

A LTFT significantly above or below 0% indicates that the global
fuel settings for the ecu do not accurately reflect your fuel system

coolant temps below 206f get full timing
coolant temps above 225f lose 2 degrees
coolant temps between those two loose 1degree
intake temps above 84f or below 34f loose 1 degree

all this is taking directly from dsmlink user guides.
print this stuff out when you go and get your cars fuel trims under control.

1. car must be fully warmed up then must be operated at cruise 40-50mph
for about 10minutes followed by idle for 5minutes to get stable LTFT.

2. compare the LTFT at idle and cruise. you want both to be right about zero
or +/- 5% or so.

3. if the two are about the same, DEADTIME setting is good.

4. if they are equal but not zero (negative), adjust the GLOBAL setting.

5. if idle LTFT is more positive than cruise LTFT, increase/decrease the deadtime

fic 650's are indeed -31% / 315uS (default)

 

[biglady112]

Tom I was saying about the knock retard in relation with my work recently with AEM. I personally tune for ZERO knock with dsmlink. AEM with the same power levels can actually go further until you really start to knock. AEM reads knock in voltage.

I recently put a 2G on the dyno. He had a fairly large FMIC, evo III 16g, FIC 650's, stock motor from throttle body to oil pan, external gate and a few other things, but those were the important things. His Turbonetics deltagate would not let him go below 20psi. This was on pump gas. His poor front mount wasn't really that great. His GM MAF was uncalibrated(I have actually never calibrated one). His fuel sliders actually were set in the positive(rich zone) and his timing was retarded as much as 5*. Car was only seeing a peak of 9-11*. I went though the car before we rolled onto the dyno. He made sure all boost leaks were gone and did a once over and a tune up before coming up.

His first pull was actually almost 350hp and 365tq. Car was too irratic and knocked out of control. 20 minutes later we got her good. air/fuel finally came back a little leaner to 10.2-10.3:1. Was off the charts for a while. Timing was down to -5*. But he left at 333awhp 342tq. This was on pump gas with an Evo III 16g.

Even though it was the most unorthodox tune I have ever had he couldn't have been happier. When he got home he called me and said the car was faster than it had ever been. Even when he had the Hahn 10cm^2 20G. Every car is going to act wierd. Just thought I would give you the insight that it might be ok to run low timing. With our race car on AEM we made 636whp at 12* timing. 12:1 and 33psi.

Steven