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      01-03-2013, 07:56 PM   #1
Nonecure
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Cobb loss of power at high RPM's

I have the Cobb Stg 1 Aggressive on 93 octane pump gas. The car pulls strong, but seems to get out of breath at higher rpm's. I installed new BMS DCS intake, but it didn't make a difference. I collected some data logs from the Cobb, but I really don't know what I'm looking at.

Anyone have any ideas what is going wrong?
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      01-03-2013, 08:03 PM   #2
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Our turbo seem to drop off around 6300 Rpm's I'd recommend just shifting at 6200ish. Also post the logs up.
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      01-03-2013, 08:13 PM   #3
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This is a graph from the data log just showing time versus rpm's. You can see the 1st gear pull that the rpms slow down over time after 5k.
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      01-03-2013, 08:21 PM   #4
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Quote:
Originally Posted by skatenc123 View Post
Our turbo seem to drop off around 6300 Rpm's I'd recommend just shifting at 6200ish. Also post the logs up.
I have an automatic (my first) and I would prefer a manual. Anyways even with using my paddel shifters, it will not shift early under wot.

I uploaded 3 log files from my AP.

Thanks, Doug
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File Type: txt datalog6.txt (15.1 KB, 27 views)
File Type: txt datalog7.txt (12.4 KB, 19 views)
File Type: txt datalog8.txt (11.8 KB, 18 views)
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      01-03-2013, 08:24 PM   #5
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what do u mean it will not shift early under WOT? or you in DS mode?
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      01-03-2013, 08:30 PM   #6
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Get a JB4 or Procede
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      01-03-2013, 08:31 PM   #7
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The few times I have tried, the car will shift at redline even if I paddle shift it at 5k or 6k. I thought I tried it under DS mode, but I will need to try it again to confirm.
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      01-03-2013, 08:35 PM   #8
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also can you shift using the shifter in DS mode?
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      01-03-2013, 08:50 PM   #9
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Quote:
Originally Posted by skatenc123 View Post
also can you shift using the shifter in DS mode?
I could if I had the JB4 or Procede, but with all the power from Cobb I need to hold on with both hands!

I will also try that. Normally too much trafic, so I have to play after hours.
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      01-03-2013, 09:01 PM   #10
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Quote:
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Quote:
Originally Posted by skatenc123 View Post
also can you shift using the shifter in DS mode?
I could if I had the JB4 or Procede, but with all the power from Cobb I need to hold on with both hands!

I will also try that. Normally too much trafic, so I have to play after hours.
Sounds fast!
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      01-03-2013, 09:37 PM   #11
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Quote:
Originally Posted by SfValley335i View Post
Get a JB4 or Procede
A correctly tuned COBB car makes as much power as a JB4 or PROcede car. So unless you know something that everyone else doesn't, please don't provide pointless tuner war comments. I personally know a few COBB cars in Portland that make better numbers than you have posted.
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      01-03-2013, 09:49 PM   #12
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power starts to fall off above ~5800 rpm or so, so I'm not all that surprised. It's even more noticeable with the AP, as you get a lot of boost down low and through the midrange.

Anyway.....You should be able to shift at whatever rpm you want in DS mode with the paddles (or shifter) as long as you aren't activating the 'kickdown' switch on the pedal. You need to train yourself not to just mash the pedal when you want WOT acceleration.
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      01-03-2013, 10:00 PM   #13
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skatenc123 just told me about kickdown in a PM. I'm sure that is why I could not shift during the pull. I will try and get a feel for the kickdown spot.

This post was to see if what I am experiencing is normal or if there is something that needs fixed or changed.
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      01-03-2013, 11:52 PM   #14
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Just curious, do you have DTC COMPLETELY disabled? It looks like you're having traction control induced throttle closures...
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      01-04-2013, 01:44 AM   #15
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I put rubber washers over the pin under the peddle to keep it from going into kick down and then re-calibrated the peddle to make sure it's opening 100%. Low cost fix and never have to worry about revving my car to 8000 rpm as I'm pulling out of a corner.
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      01-04-2013, 08:19 AM   #16
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Quote:
Originally Posted by Wedge1967 View Post
A correctly tuned COBB car makes as much power as a JB4 or PROcede car. So unless you know something that everyone else doesn't, please don't provide pointless tuner war comments. I personally know a few COBB cars in Portland that make better numbers than you have posted.
correctly tuned? haha correctly tuned has different meaning to each tuner. Yes I do know something that you dont, JB4 and Procede can make more whp than a "properly tuned cobb".

Thats great that you know of cobb tuned cars that make better numbers than Ive posted in 2008

Young one a lot has changed since 2008... You haven't been around long enough to remember what has happened.
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      01-04-2013, 10:06 AM   #17
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Quote:
Originally Posted by SfValley335i View Post
correctly tuned? haha correctly tuned has different meaning to each tuner. Yes I do know something that you dont, JB4 and Procede can make more whp than a "properly tuned cobb".

Thats great that you know of cobb tuned cars that make better numbers than Ive posted in 2008

Young one a lot has changed since 2008... You haven't been around long enough to remember what has happened.
Well, considering I started tuning in the mid 80's doesn't exactly make me a young one. So before you make comment you should at least know what you're talking about. If you're making such big numbers then update your information to keep people from making comments about your average numbers. My recommendation is stop living in the past grandpa. Yeah a lot has changed and COBB has stepped up to the plate and has come a long way in the past year. Now both JB and PROcede are flashing to overcome limitations with the piggyback. I'm personally making over 430 whp on FFTEC's Mustang, and that is a PROcede stock turbo record on that dyno. But this thread isn't about JB4 or PROcede so your comments are still your pathetic attempt to start a tuner war. I'll say it again, if you don't have anything productive to say, don't say anything at all. Feel free to take this offline if you want. Or we can take it to the track. I'll be at the next shift sector airfield event in March, so you can put your numbers where your mouth is. BTW, I don't remember seeing you at the last event. Funny how there are two types of people here, those who do and those who just talk about it. I'm assuming your a talker because you apparently only know what you have read in this forum. See you at shift sector grandpa.
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      01-04-2013, 10:10 AM   #18
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Without a FMIC the basic Stage 1 tune is going to drop off pretty rapidly anyway, by design.
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      01-04-2013, 10:11 AM   #19
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Get protuned.
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      01-04-2013, 11:04 AM   #20
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I am noticing a bit of hesitation that I can feel in the peddle under WOT. Almost feels like rapid studder. This only happens in 6th gear on a pull starting anywhere from 75-80mph. when i go through the gears at WOT i don't notice this. I have had the tune just shy of 100miles but have used it in the past on other maps and noticed this too. Is this common to happen and would a pro-tune fix this? thanks
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      01-04-2013, 11:06 AM   #21
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Quote:
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Without a FMIC the basic Stage 1 tune is going to drop off pretty rapidly anyway, by design.
+1 good point, a single pull on the OE intercooler will skyrocket charge temps. Even the more aggressive Stg1/2+ maps pull down boost to around 12psi below redline. N54s are not very rev hungry engines to begin with.
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      01-04-2013, 11:10 AM   #22
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Quote:
Originally Posted by MSport35TT View Post
I am noticing a bit of hesitation that I can feel in the peddle under WOT. Almost feels like rapid studder. This only happens in 6th gear on a pull starting anywhere from 75-80mph. when i go through the gears at WOT i don't notice this. I have had the tune just shy of 100miles but have used it in the past on other maps and noticed this too. Is this common to happen and would a pro-tune fix this? thanks
Generally speaking it's wise to avoid giving it the beans in 6th gear. If you're doing a pull start out in a lower gear, 6th is a cruising gear.
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