COBB DataLog

[zakyzozo]

Can someone please take a look at my datalog and tell me if everything looks ok? I do not have any experience interpreting the data. Sometimes when I floor it and shift gears, it will make a slight backfire sound. I have 20K miles on most of my engine, and 4k miles on the long block. New injectors, ER chargepipe, Active 5" Intercooler, and BMW performance exhaust with y-pipe. Thanks and much appreciated.

[brusk]

That's a pretty conservative map, what tune is it? Do you have downpipes? It shouldn't make any backfire and it doesn't look like it's running rich enough to ignite anything for a backfire.

[zakyzozo]

Sorry I forgot to mention it is stage 1+ aggressive. No downpipe. It is like a pop sound, and it only does it when I come out of 1st gear. It also did this in the stage 1+ sport map. I assume I cannot run any of the stage 2 maps until I get a downpipe, but i am still under warranty.

[135Pats]

If you give it sudden WOT higher in the rev range, you are evacuating a huge volume of exhaust gas very quickly. That pressure difference can create the loud crack/pop noise you may be describing.

Can you post the log to datazap.me? Far easier to digest in that format.

[zakyzozo]

Originally Posted by 135Pats

If you give it sudden WOT higher in the rev range, you are evacuating a huge volume of exhaust gas very quickly. That pressure difference can create the loud crack/pop noise you may be describing.

Can you post the log to datazap.me? Far easier to digest in that format.

I posted it to datazap, how do I share the log so others can view it?

[135Pats]

Originally Posted by zakyzozo

I posted it to datazap, how do I share the log so others can view it?

just post the exact url link

[zakyzozo]

http://datazap.me/u/zakyzozo/stage1-...mark=2073-2704

[135Pats]

Originally Posted by zakyzozo

http://datazap.me/u/zakyzozo/stage1-...mark=2073-2704

You need to be 100% WOT for the log to make any sense. There are some throttle plate closures and it looks like you didn't give it full throttle for some of these pulls.

[zakyzozo]

Originally Posted by 135Pats

You need to be 100% WOT for the log to make any sense. There are some throttle plate closures and it looks like you didn't give it full throttle for some of these pulls.

So just put the pedal to the metal through the first three gears and only log that run opposed to logging normal driving? How do you tell there are throttle plate closures? Thanks for the advice.

[135Pats]

Originally Posted by zakyzozo

So just put the pedal to the metal through the first three gears and only log that run opposed to logging normal driving? How do you tell there are throttle plate closures? Thanks for the advice.

TPS= throttle plate

You want to have a WOT log of at least a full 3rd gear pull from 2.5-6K+ revs. Ideally we’d be looking at it into 4th to see how things look post-shift, but I understand speed is getting up there at that point.

There is no need for a 2nd or 1st gear log. Not enough load. Start in 3rd.

[houtan]

Keep in mind, to do a third gear pull from 2.5 K, you have to get the throttle all the way down without pushing in the kick down switch. Took me a few tries but you'll get used to it. I do it barefoot so I have better feel for the kick down switch.

[zakyzozo]

Originally Posted by houtan

Keep in mind, to do a third gear pull from 2.5 K, you have to get the throttle all the way down with pushing in the kick down switch. Took me a few tries but you'll get used to it. I do it barefoot so I have better feel for the kick down switch.

How to I push activate the kick down switch exactly? How would i know that i activated it correctly? Dont know if this matters but my car is a manual.

[Nugget]

If your car is manual then there is no kickdown switch.
Just roll along around 2000rpm in third gear on a straight flat road (preferably with no traffic or side streets) start the log then push the accelerator all the way down and rev it all the way through third gear, if you have the room then keep going into 4th. Slow down safely and stop the log.
eg. http://www.datazap.me/u/nugs/ptf-e30...&data=1-4-5-15
See how the accelerator pedal position is 100% all the way through third into 4th, that is what you want.

[houtan]

Sorry edited my prior post. Should have read "without" pushing the kick down switch. Not "with". As nugget said, kick down switch is only on an auto/dct.

I was viewing on my phone earlier and didnt realize you have a manual tranny. Please disregard my prior post. My bad.

[brusk]

Keep in mind he's not strictly posting a log to see how the tune is doing he's experiencing some hiccup/backfire between shift even from 1-2 shift so even though that doesn't load up it wouldn't hurt to log. If you could go somewhere get setup and hit the log button right before you go and right after you stop flooring it. Wouldn't hurt to get a 1-2-3-4 run if you can and say which times it had the issue.

[zakyzozo]

Thanks for your input, I will try and do this tomm and upload new logs. Thanks again for your help

[edisapimp]

Originally Posted by zakyzozo

How to I push activate the kick down switch exactly? How would i know that i activated it correctly? Dont know if this matters but my car is a manual.

I was chuckling throughout the whole thread, but this made me burst out laughing. Thank you for that.

Please let us know when you get some good logs! We look forward to helping you!

[vivanapoli806]

I'm thinking about doing a log myself. Never did one before. I have steptronic trans so should I just put it in manual mode and put it in third gear and do a wot pull ?

[135Pats]

Originally Posted by vivanapoli806

I'm thinking about doing a log myself. Never did one before. I have steptronic trans so should I just put it in manual mode and put it in third gear and do a wot pull ?

yes. 100% WOT, do not hit the kickdown switch, shut up all traction nannies before hand so there are no traction related throttle closures. Then post it to datazap.

Everyone should log frequently. I really don't view it as optional, you want to make power then be diligent. Don't have to do it every day or anything crazy, but should be something that you stay on top of.

[zakyzozo]

Originally Posted by edisapimp

I was chuckling throughout the whole thread, but this made me burst out laughing. Thank you for that.

Please let us know when you get some good logs! We look forward to helping you!

Haha, thats awesome. Yes I know, noob here when it comes to some things.

[zakyzozo]

Finally was able to do a 3rd gear run. Could one of you brains have a look at my datalog and let me know how everything looks? Not this run, but when I was racing against a friend tonight, the car kinda sounded like it was breaking up when I got to about 6500rpm, perhaps fuel cutoff? And at that moment, the accessport was showing 17lbs of boost. As a refresher, I am running Stage 1+ aggressive, with IC, chargepipe, and BMW PE. New engine only has 4K miles on the longblock, other components 20K. Thanks for your input.

http://www.datazap.me/u/zakyzozo/3rd...og=0&data=3-12

[Ski Killset]

Is there no data for individual cylinder timing or correction? Have you had your intake valves cleaned?