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

[mastadogg2]

very nice. ya i dont know anything when it comes to aem ems. i doubt i could even load the base maps .. 333awhp is pretty damn good on pump. im one of the lucky persons i guess because i made 302whp on base settings i didnt even modify 1 slider on dsmlink. im tryin to make it as easy as possible for this guy to get his trims under control. i know tuning can be a headache if your unsure of something. but ya the 2g's are wierd. 3deg+ is a pretty bad detonation.

what you recommended to this guy (starting over from scratch) I highly agree and recommend he does that as well. it will make things easier. some dsm's can really be a pain in the ass tho when it comes to tuning. i hope he prints out the stuff i copied from dsmlink guides and attempts to do that. after he gets his trims udner control then i think it will be much easier to assist him with his tuning.

 

[olmytsi]

You are lucky to get this many people willing to help you!
Definitely get the fuel trims in check and play with the fuel first. I honestly think you should leave the timing at 0 until you dial in the fuel (afr's).

PS: once you get the dsmlink username, you will find PLENTY of information, just search and read.

 

[Turbocharged]

You need to dial in the injectors before tuning. ECM tuning burns a generic setting for your injectors but you STILL need to dial in the injectors. My chip was burned with a global setting of -47% w/ deadtime of 315. I had to adjust that to -34% w/ deadtime of 210! Each car is different. It should only take you a 15 minutes to zero out the mid and lo LTFT's after cruising and idling a little. Dont even look at STFT's.

 

[biglady112]

After you get the trims dialed in. YES look at stft. This is how you tune the car real time for wot tuning. It will make a difference on a wideband. I wouldn't have mentioned it if it wasn't important.

Steven

 

[RavenX]

I personally have never tuned using the STFT. I just use the wideband and gm 3.3 bar. You guys also forgot to mention he hasn't done a boost leak test yet so if he has leaks that will definately mess things with his fuel trims.

Ps: Don't you think 10.2-10.3:1 is kinda rich? At least thats what i have been told and from experience. I usually tune for 10.6:1-11.0:1 on pump gas.

 

[-DSM2NR-]

I'll do a boost leak test the first thing tommorow morning. Then I'll adjust Global since it obviously needs adjusting because it's at -12.5.

Thanks guys, I appritiate your help

 

[Turbocharged]

After you get the trims dialed in. YES look at stft. This is how you tune the car real time for wot tuning. It will make a difference on a wideband. I wouldn't have mentioned it if it wasn't important.

Steven

This is not correct. When you are WOT, the ECU goes into open loop (not closed loop as you stated #47) and no longer uses LTFT's, STFT's, or O2 sensor measurements to determine how much fuel to add. For those who havent taken courses on the subject, open loop process control is basically when a system enters a mode where it only uses intrinsic functions (or in this case the enrichment table as shown by mastadogg2) instead of using sensors/outputs to make calculations. The system therefor has NO feedback control for its fuel calculations. The ECU "sees" how much air is entering the MAS and calculates how much fuel to add based on the tables. LTFT's and STFT's are not used in the open loop calculations.

Also, STFT's are calculated based on O2 readings (and others sensors Im sure). So why would it be okay to tune with STFT's and not O2 or other sensor outputs?

I personally tune for zero knock, 18-20* of timing (if possible under the given conditions), while keep an eye on the EGT's. Dont even log O2's as they are worthless. Ideally you want to tune with a wideband O2. My advice is to get a very good tune with the tools you have, then go to a dyno and use a wideband to fine-tune.

Register for the DSMlink group, the people there are very helpful.

 

[biglady112]

Of course it was rich. But that was all the car would do. It would knock any leaner than that. Remember, every car is different. Didn't appear to blow any black smoke under boost out of the exhuast or dump.

Steven

 

[-DSM2NR-]

I adjusted global to -30% leaving the dead time at 315 but both LTFT's stayed at -12.5%...........

 

[RavenX]

I adjusted global to -30% leaving the dead time at 315 but both LTFT's stayed at -12.5%...........

You have to adjust the deadtime as well. Try going to a deadtime of 330 or 345 and see what that gives you. Also Ltft Lo will not changed until you drive for a few minutes and then idle for a few minutes. Ltft Mid is the pain in the ass to set and it will take the longest. Some cars they get dialed in easy while others take a while. Just get within +-/5%

 

[mastadogg2]

yup exactly what raven said......... sometimes fuel trims can be stubbern to and it may take up to like 1 hr just for them to adjust.. i had it happen to me already! best thing to do is take it out on a highway or interstate where you can just cruise at a steady 40-50mph for about 10-20minutes or so.

 

[mastadogg2]

btw raven .. 113mph trap and only a 13.8!!!!!!!!!! jeez.. was it the track or your driving? .. either way 113mph trap is movin! i should be around 110-111. you should be in 12's with a 113trap! how is your traction with that car? on mine i only half issues mostly in 1st and 2nd, it will spin 2nd until 60mph or so with my 225/45/17's. im guessing your spinning 3rd up to around 100mph or so with 370whp????

 

[olmytsi]

Is using the airflow sliders to tune the fuel trims only good if you have the maft?

 

[mastadogg2]

no, leave the sliders alone unless you want a inaccurate airflow reading. I believe they were put into dsmlink mainly for the 1g guys that overrun there 1g maf's & guys that hack 2g Maf's.

read this: http://www.dsmlink.com/details-airflow.html

 

[scottsee]

Airflow sliders are designed to compensate caculated airflow with known actual airflow. BoosEst & 3.3barmap..

(14.7 + 3.3barmap boost) / (14.7 + BoostEst boost) = Value- 1 =+/- Ajusted airflow value

If I knew your LTFT were not dialed in to around +/-5% I would have told you that your closed loop fuel delevery would be extreamly off. Do you have your base fuel pressure set? If you don't have an AFPR I would strongly suggest getting one now. Without known fuel pressure trying to tune AFR's will be nearly impossable without a wideband becasue caculated fuel enrichment will be off from actuall fuel ratios. Your log shows alot of airflow for the amount of g/rev your seeing.

Please Log your TPS info, LTFTlow, LTFTmid, MAF, and post a log when you can. You shouldn't be running WOT untill you dial in your fuel trims.

 

[RavenX]

btw raven .. 113mph trap and only a 13.8!!!!!!!!!! jeez.. was it the track or your driving? .. either way 113mph trap is movin! i should be around 110-111. you should be in 12's with a 113trap! how is your traction with that car? on mine i only half issues mostly in 1st and 2nd, it will spin 2nd until 60mph or so with my 225/45/17's. im guessing your spinning 3rd up to around 100mph or so with 370whp????

Haha I know. That was with a 2.4 60ft. Its not my driving i just need drag radials. Usually when i go to the track i just do MPH instead of trying to get a low ET. Its kinda hard on street tires and a shitty track prep to get good times. That 113 was at 21psi on pump gas alone. I have yet to do a good run with the meth running. I tried that last night but the car was breaking up on me on at 28psi with the meth. It ended up being the spark plugs so i'll be back again next week hoping for 115-118mph traps As for spinning tire i only have problems in first and second only. I have no issues in third yet . I also run 225/45/17 tires and its alot nice than those pesky 205/55/16 stock tires haha. I also have the switchable boost control using the fpr solenoid and the dsmlink nitrous controls. You should do that. One of the best mods i have done. Works very well i used it for the first time last night. Just need to see when i want dsmlink to switch to high boost. I also rev to 8,000rpms so on that 113 run i actually crossed the line in 3rd gear almost hitting the limiter at 8k. Lots of fun though

 

[mastadogg2]

nice... how exactly are you controlling your boost?? i run a mbc, a hallman pro , does this require a ebc? if you went to a preped track i bet you could pull some 12's on your street tires pretty easily.

 

[scottsee]

yeah you need an EBC to set your boost condole via dsmlink nitrous controls. Hopefully the next version of dsmlink will have veritable boost controller so we won't have to use the nitrous controls for it. Sucks that their is only one veritable controller. I would like to do the same thing but have my water/alchy kit wired into it at the moment.

Nice 0-60!

 

[mastadogg2]

are you referring to my 60-100 video?

 

[RavenX]

Actually no you don't need a EBC. I have a Hallman Pro MBC. Since i have a external gate my stock wastegate boost is 18psi which is perfect. Basically the fpr solenoid is a 3 way valve system. So its usually at 18psi and when the conditions set in the nitrous controls are met it switches the valve and give me 25-26psi. Whats so good about it is that since i have the meth kit i'll be running lots of boost. If by some reason the meth fails i could seriously damage the motor so in the nitrous controls if dsmlink sees 3-4 counts of knock it automatically tells the solenoid to switch to my stock boost 18psi in this case until the knock goes away. Comes in handy really.

 

[-DSM2NR-]

Alright, I'll try adjusting dead time as well. One thing that got me worried is the fact that a CEL came on "Fuel Trim Malfunction" as soon as I moved global to -30%. I moved it back to -31% after that. I hope I didn't mess anything up.

 

[-DSM2NR-]

And another thing that I should probably mention is that I use 91 octane. The highest we got here is 92. This is probably making lowering knock even harder, isn't it?

 

[RavenX]

And another thing that I should probably mention is that I use 91 octane. The highest we got here is 92. This is probably making lowering knock even harder, isn't it?

Yes its going to be that much harder tuning because of the gas. Your best bet to remedy this is to buy a meth kit or running a mix of race gas and pump. However the meth will pay for itself in the long run. I haven't seen much 91 octane logs on dsmlink forums but am sure the timing was low and the air fuel was somewhat rich.

 

[-DSM2NR-]

I just found out that a gas station in town sells race gas. I want to mix pump with race gas. What kind of mix should I put together? 50/50?

 

[biglady112]

I don't like mixing. Just take the fuel rail feed off, and pump it out with dsmlink. But if you must mix it, more race gas than pump. Maybe 70/30 or 80/20.

Steven