CMiller95

Hey all,

I just finished installing my cam and I am working on tuning it. I am utilizing EEHack for datalogging and TunerCATS for tuning it. On my first drive utilizing a stock tune I was running pretty lean. So, I went into the MAF table and edited the AFGS by adding %10. This definitely made the car run alot better and brought my BLM's down. For some reason at partial throttle around 3000 rpm it occasionally falls on it's face, it fells like a complete misfire across the board. Looking at the datalog the MAF value spikes to 450+ g/s which is very unrealistic. I have not run the car at WOT as I know that's a different story and I want to get partial throttle down first. I have done days worth of reading so I have a pretty good idea as to what is going on.
Car info: cam: 222/226 @ 0.050, .530 life, 113 LSA, Headers, and a new Petris Opti

It wont let me post my datalog so, if someone is willing to help I can email the file to you or send it to you however you would like.

Thank you!
-Colton

93LT1

Please keep us posted on your findings and progress.

FrankieD

sent you a PM

CMiller95

Sent you an email

CMiller95

Update:

I finished installing my wideband today and took it for another drive. The same issue arose with it cutting out right around 3000 rpms and looking at the datalog it was once again the MAF saying something like 400 g/s out of no where. So, i decided to run the car in speed density and I unhooked the MAF. This made a HUGE improvement. It was really running on the rich side as my new datalog shows but there was no miss and it was smooth across the board. So for now I will tune it in speed density and go from there

Colton

FrankieD

I took a look at your datalog and I can see 3 events where your MAF took a spike. I call these spikes anomalies because they just randomly show up for 1 timestamp and return to normal. When they do occur I cannot see any pertinent change in your engine data. I would just take them as unexplained occurrences. If they continue you may want to try replacing your MAF and see if it goes away.
The MAF spikes occurred at the following timestamps in the datalog:
#1522@158.7
#4360@455.6
#5198@543.4

CMiller95

Thank you for looking at it! I think I am just going to run it and tune it in speed density and later move up to MAF (and installing a new one) after everything is lined out. Thank you for your help. If I am not mistaken tuning with speed density is observing the AFR on the RPM, AFR, and MAP chart and making adjustments to the Volumetric Efficiency.

FrankieD

Sounds like a great plan. You may also want to look at adjusting your BLM Cell RPM Boundaries and BLM Cell Map Boundaries. By doing so you will more likely get better tuning resolution for VE adjustments

CMiller95

Frankie,

Can you expand on what you mean by adjusting those boundaries to increase the tuning resolution? I am pretty sure I know what you mean but I am new at this

Thanks!
Colton

bjankuski

I do not like to modify the MAF tables unless you are sure they are incorrect. More then likely your injector constant or injector data was not adjusted correctly for the injectors you are running. The spike in the MAF readings could be an issue with a poor transition from on MAF table to the other, the MAF tables must always be increasing in value from one table to the next. If you have any one cell higher up in the frequency curve that is lower then the proceeding cell it causes funny issues with the EE defination file.

CMiller95

I have the same injectors and at the same pressure as factory. What table do I modify to tune it utilizing the MAF?

CMiller95

I looked at my adjusted tables and I did not increment table 3 up %10 like I did the other 3 which resulted in a lower AFGS value as the table increased. So that may be my problem, I should get a chance tomorrow to retune it and see what happens.

bjankuski

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Good luck, I hope that takes care of your issue.

CMiller95

I decided to start with running it in speed density and I got it pretty close throughout the table. I ranging from 124-132 BLM so a little more tuning is needed but not bad progress for today!