Cobb AP datalog Pull

zx2man

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2009 mazdaspeed 3
Alright..so just did a datalog run with my 09 ms3. Running stage 2 sf 91oct.
did a nice hard 1st through 4th gear pull..was about 100 mph at 6000 rpm in 4th before i slowed down and ended the log. Any imput would be very very welcomed for sure. THANK YOU!
 

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ps........... after i hit 100 mph...i engaged the clutch and poped it into neutral to slow down therefore that my explain how my numbers get crazy at the end there.
 
Does not look too bad. You have some KR and your WasteGate is trying to stop your boost but other than that it does not look too bad. AFR's are ok.

Do you not have access to 93oct fuel? If so, run that and it should help the KR.

Also in the next log be sure to get your Long Term Fuel Trims so we can see what they look like as they are important as well.

Other than KR and WasteGate, you look good from what I can see.
 
Would a upgrade bpv help at all? 92 oct is the highest available at the pumps. And that is what I use. But all in all im not in any danger of hurting my engine right?

:)
 
Well you want to keep KR out if at all possible, specially under WOT, but each of us typically have a little even under WOT. 4deg is a tad high for me, but then again I had 7deg 100% stock do meh.

A BPV will not really help your KR. Breathing mods might to some degree, but really Fuel would help. Try a different station. I personally use Shell as it seems to be the best for my car.
 
I have a 76 gas card so thats what i use..alwas seemed to be pretty good gas...Any good octane booster you can reccomend??..going stage 1 sf help at all or stay with stage 2..its gonna be while before i get the cobb dp.
 
Just got email from head tuner Tim Baily at Surgeline tuning...gonna try to run stage 1 sf. Wish me luck :)
 
Based on that log, your AFR, boost and fuel pressure #s look good but those knock readings need to come down a bit. They're not terrible but you want to get those down as low as possible, preferably zero under WOT if possible.

I actually just had my MS3 tuned this past weekend. Took my tuner pretty much the entire day but I'm still getting a bit of knock (nothing higher than 2.5 under WOT from time to time thus far) - everything else is looking good. We still need to address the issue of overboosting and triggering the ECU's boost cut which is very annoying. We tuned off the Stage1+SF 93 octane map as we have access to 94-octane up here.
 
Yeah its all about the tune!!!....the best of luck to you on that. I told Tim Baily that I dont want to do custom tune till i get my cobb dp installed. I should be ok..just drive it around and break these maps in and keep dataloging...what kind of dyno numbers are you pushing derspi? with the exception of the ets ic,were pretty close on the mods :)
 
Based on that log, your AFR, boost and fuel pressure #s look good but those knock readings need to come down a bit. They're not terrible but you want to get those down as low as possible, preferably zero under WOT if possible.

I actually just had my MS3 tuned this past weekend. Took my tuner pretty much the entire day but I'm still getting a bit of knock (nothing higher than 2.5 under WOT from time to time thus far) - everything else is looking good. We still need to address the issue of overboosting and triggering the ECU's boost cut which is very annoying. We tuned off the Stage1+SF 93 octane map as we have access to 94-octane up here.

mind saying what kind of numbers your putting down?
 
I never did experience boost cut when i was doing my pulls..car kept pulling and pulling...but im now going to the stage 1 sf map to see if my knock goes down at all...Tim Baily said that my knock was alittle high and it wasnt too safe..now true alot of people on here are running some knock and thier doing fine for the most part..but when possibly the best tuner in the country says to go stage 1 or custom tune..you take his advise lol..so well see how it goes...stage 2 was made to run with a catted dp..these maps are very picky on what parts you run with..the maf is prabaly the most important..but you really gotta pay attention..I do plan on gettin a custom tune when i get my dp...just want a map that will hold down the fort so to speak before that time comes...I think that when your dealing with the ms3 and your plans to include the accessport in your mod list..then you should accept that ultimatly you need a custom tune for your car to run the way you want it...but on a lighter note yeah pushing 20+ lbs of boost through you car is ummm fun(drive)
 
The log is showing wastegate solenoid valve duty of >90% (and sometimes maxed out) at >5000 RPM.

A higher numerical value = more boost.

If my understanding is correct 0% wastegate is fully closed = more boost. 99% is fully open trying to bleed off boost.

Maybe I have it backwards, but that is how I understood it.

FYI - Just researched this to verify for myself. I was in fact correct. 0% is closed 99% is fully open, IE it is trying to stop the boost from building. So as I mentioned above, your WG is fully open trying to stop boost from building further. No big deal but it would be better to tune the car than have the WG struggling to keep the boost from over-boosting. FYI - The Max WG I get is 47% to maintain 19PSI dropping to 17PSI at 6100RPMs.
 
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mind saying what kind of numbers your putting down?

Not gonna do a dyno pull until I'm pretty happy with the tune. And as of now, we've still got a couple of issues to finesse until I can call the tune complete. Although getting more power is the point of all this, I'm more concerned with getting a good, safe tune for the time being as this is my DD. The push for more power will come later.
 
If my understanding is correct 0% wastegate is fully closed = more boost. 99% is fully open trying to bleed off boost.

Maybe I have it backwards, but that is how I understood it.

FYI - Just researched this to verify for myself. I was in fact correct. 0% is closed 99% is fully open, IE it is trying to stop the boost from building. So as I mentioned above, your WG is fully open trying to stop boost from building further. No big deal but it would be better to tune the car than have the WG struggling to keep the boost from over-boosting. FYI - The Max WG I get is 47% to maintain 19PSI dropping to 17PSI at 6100RPMs.

Please...

Have you noticed any electrical connectors on the turbo or the wastegate actuator?

There aren't any. That means that the ECU quite obviously has absolutely no way of knowing how much the wastegate is open (and there is no reason for it to know).

The ECU is controlling the boost in a closed loop manner, with the wastegate solenoid valve (as mentioned in my previous post) as the control element and the MAP sensor for feedback.

Wastegate duty is referring to the duty cycle of the (electronic) wastegate solenoid valve (0% is closed, 100% is fully open), and not the (mechanical) wastegate.

The ECU opens the valve more to increase the boost pressure (or spool-up the turbo), and closes it to decrease the boost.
 
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Semantics

I just love it when two guys who usually know what they are talking about argue when in fact they have no disagreement.
Bravnik is saying that with the duty cycle at zero you are making more boost than with it higher, because the wastegate is closed, not bleeding off boost.
Matsuda is pointing out that the high duty cycle shows that boost is high because the ECU is trying to bleed it off by opening the wastegate.
Both are true statements. Stop the pissing match before it starts and derails the thread, okay?
 

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