Advice - Regarding my Build

furian76

furian76

Forum Member
I have posted about my issue and build in the other Unnaturally Aspirated section before, well a portion anyways. But, I think its come to advice at this point.

Bone stock, Jeep ran 14.2, felt and performed as expected for location and age.
Had a shop that came highly recommended for my area to install a low boost twin turbo application. Work looks professional and many others from track to car shows said they like the workmanship.
BUT, that's where the good stuff stops, 6 months of LIMP mode issues finally resolved as it was their tune. At the track and it finally ran a 14.9 with horrible shift lag.
Installed a Karma TCM which improved the shifts, but now it runs a 15.3 at best.

Everything feels quick, but something is definitely off. Listening to the engine, no ticks, no dings, not even a belt squeak. But anything more than that and I am at a loss. I purchased an MPVI2 so that I can scan log in the software/hardware they used to tune the vehicle. But I am not getting much out of my tuner in the way of help to figure out the issue.

I'd like to just take it to somebody to have them look it over, go through all the tuning, and see if anything stands out as the issue. But every time, some one gives me info and I send to my original tuner, they have a reason for that issue. Such as the LTFT being at -32 all the time. They say it is because they turned off the O2 sensor for LTFT.

Anyone have any recommendations, suggestions, or trains of thought that could get this brick moving the way it should? I have very few shops with tuning capabilities down my way. And with the vehicle being a 4 wheel on demand, it really needs an AWD dyno.

If anyone wants to see the tune or scan logs, let me know, I have them, but didn't want to post clutter. And I am not looking for a free tune, but definitely willing to pay if a shop thinks they can fix it or solve the issue.
 
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What are the details of the Jeep - year, model, engine size? You mentioned "down here" - where are you located?
 
Did they give you a dyno sheet with A/F that you can post? Just curious to see where it was at and compare it to a stock dyno sheet of an SRT-8 which I am sure I can find 1000 of online.

Tx.

-Geoff
 
Everyone that has seen this dyno and knows the specs, says this thing should easily be running mid 12's. But I am no where near that at 15.3

Here is a stock 2006 for reference. Not mine.
11979-2006-Jeep-Cherokee-SRT8-Dyno.jpg
 
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Man, I wish they would put RPM on the X-axis on that dyno graph instead of MPH. If you look at the boost chart, it doesn't start making boost until 100 mph. Did he go full throttle at 60 mph or kick it down at 100 mph? If he kicked it down at 60, it would mean that your turbos are a restriction from 60-100 mph. Did he pull it through three gears on the dyno? Are those shifts at 90 and 140?

-Geoff
 
honestly, questions are good. Although, I may not have all the answers.
What I do have is video.

I believe he is manually shifting it through the gears. Your description of the boost kind of makes sense. But I have no way to confirm this really. Main reason I am looking for other inputs and possible another location to go over this thing. Here is the videos of this thing he posted. You can see his shifting.

https://youtu.be/4CFimo934Bg (Dyno)
https://youtu.be/V5br02Frc1A (Run Down)
 
I was looking over my build list. It shows a boost controller in this thing. I don't remember seeing one anywhere. I may have to look now. between what you said and the possibility that something hit the controller, maybe the boost is jacked up or something.

Here is a link to the zip file containing the tune and log file if anyone wants to view this stuff.

https://drive.google.com/file/d/15ARbSPRgQ0R_uXhxswupYjmHbwfV3EOk/view?usp=sharing
 
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furian76 said:
I was looking over my build list. It shows a boost controller in this thing. I don't remember seeing one anywhere. I may have to look now. between what you said and the possibility that something hit the controller, maybe the boost is jacked up or something.

Here is a link to the zip file containing the tune and log file if anyone wants to view this stuff.

https://drive.google.com/file/d/15ARbSPRgQ0R_uXhxswupYjmHbwfV3EOk/view?usp=sharing
Click to expand...

It says boost controller, do you have a gauge, or anything that shows if it is making boost/pressure in the intake?

Seeing what Geoff stated above, I'd think/hope that they hold it in gear and make the pull, but if it doesn't make any boost until 100mph, it's all pretty useless unless you're running a Supra on the highway from a roll...
 
sofa king said:
It says boost controller, do you have a gauge, or anything that shows if it is making boost/pressure in the intake?

Seeing what Geoff stated above, I'd think/hope that they hold it in gear and make the pull, but if it doesn't make any boost until 100mph, it's all pretty useless unless you're running a Supra on the highway from a roll...
Click to expand...

No Gauge that I can see. I looked up that controller on the website and it shows a digital readout. So I am going to fine tooth comb my vehicle tonight. And honestly, the build was supposed to make power below 100Mph. That was my goal going into it and this was the system they recommended. I didn't want a S/C as it didn't scale as well for my future plans.
 
Detatch the boost pipes and run it. Should still run 14.2 with no boost. If it doesn't, you got screwed.
 
I am not familiar enough to know what may fuck something up. Do you mean just disconnect near the intake and just let it push air into the hood area? Or somewhere else?
 
AutoRoc said:
Detatch the boost pipes and run it. Should still run 14.2 with no boost. If it doesn't, you got screwed.
Click to expand...

It sounds like his tune might still run it at 10:1 though, so I am not sure that would help. Do you think it will still pull at 10:1 NA?

-Geoff
 
Well I have boosted stock engine with a tuned PCM. When I twist my boost knob, my wastegate gets restricted and I get more boost. When I get more boost, my tune adds fuel and pulls timing. I can run 7psi, 8, 9, 10, 11, 12, 13, 14, 15psi because I only have a 1 bar map sensor. These are set curves. I imagine if I unhook my intake piping, my car would run just like stock, around 280hp...
 
furian76 said:
I am not familiar enough to know what may fuck something up. Do you mean just disconnect near the intake and just let it push air into the hood area? Or somewhere else?
Click to expand...

Well not really because you don't want the turbos to spin without resistance on the compressor side. I would unhook the exhaust before the turbos so they don't spin and then unhook the charge pipe to the throttle body. The engine alone has to run properly before any boost is added.
 
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