Welcome to the North American Subaru Impreza Owners Club Saturday August 2, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Engine Management & Tuning > UTEC

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 07-27-2006, 12:46 AM   #1
SloRice
Scooby Specialist
 
Member#: 44351
Join Date: Sep 2003
Chapter/Region: MWSOC
Location: Cincinnati, OH
Vehicle:
2004 Mitsubishi Evo
701whp 9.91@146

Default UTEC, DTEC and Speed Density

Since we all know about the new speed density firmware coming out, I am going to be getting tuned with it next weekend. So we started working on the blow through MAF setup tonight. After talking to Nathan@TXS, tmarcel and Tim Bailey, we went ahead and cut the MAF wires to extend them and used shielded wire on the appropriate MAF wire. Once it was all done, we wanted to start it just to see if it would. My car is already tuned for a BigMAF which is ~3" diameter and the blow through pipe we used is 2.75" diameter, so if it started, it was going to be pig rich and it was....idled at 11:1 AFR. Since I'm only going to be using the MAF for idle control, I didn't care to much about stuffing a 3" or larger diameter pipe in there for MAF resolution. I just want the car to idle normally and it did...rock solid at 900RPM's. Blipped the throttle and it cames right back to 900RPM. Hell it idles better now than it used to, just a few points richer AFR. I have about 4" inches of straight pipe on either side of the MAF sensor. So get my tuner to recalibrate the AFR in the ECUTek and UTEC and it should be good to go!!

Now the next step in the process is to see if I can split the signal off of the DTEC MAP sensor and run it into the signal line on the stock MAP sensor. Then have my tuner recalibrate the ECU and UTEC for the new MAP sensor. That way I have a 4.5 bar MAP sensor to tune the UTEC with instead of the 23psi limit the stock MAP sensor has. I spoke to both Mark and Nathan at TurboXS and they said it might work, but they aren't sure. If not, I spend $100 and get another MAP sensor from them and wire it in where the stock MAP sensor is. Does anyone have any thoughts on this as this is my main concern now. I cut open the shielding for the DTEC MAP sensor and the last picture is what's inside. Anyone know which one is the signal wire to tap into? Also did I screw myself by cutting the shielding?

And pics for the kiddies!!







* Registered users of the site do not see these ads.
SloRice is offline   Reply With Quote
Old 07-27-2006, 11:01 AM   #2
SloRice
Scooby Specialist
 
Member#: 44351
Join Date: Sep 2003
Chapter/Region: MWSOC
Location: Cincinnati, OH
Vehicle:
2004 Mitsubishi Evo
701whp 9.91@146

Default

slow day in the UTEC section I guess.
SloRice is offline   Reply With Quote
Old 07-27-2006, 11:35 AM   #3
InfamousDX
Scooby Guru
 
Member#: 25413
Join Date: Sep 2002
Chapter/Region: Tri-State
Location: North NJ
Default

Not that I offer help but a question... how many wires do you have to extend? All of them (how many is that, lol)?
InfamousDX is offline   Reply With Quote
Old 07-27-2006, 11:47 AM   #4
x99percent
Scooby Specialist
 
Member#: 27108
Join Date: Oct 2002
Chapter/Region: MWSOC
Location: Detroit-ish, MI
Vehicle:
2004 STi
2004 A4

Default

It *should* work... I did a similar thing with my factory MAP sensor over a year ago, when I wanted to run an unmolested MAP signal into the ECU while using a UTEC.

Obviously, the problem is figuring out which wire is which! Did you cut into the wire between the MAP sensor and "4-way connector" as shown on page 6 of the manual? ...time to pull out the voltmeter!
x99percent is offline   Reply With Quote
Old 07-27-2006, 01:07 PM   #5
SloRice
Scooby Specialist
 
Member#: 44351
Join Date: Sep 2003
Chapter/Region: MWSOC
Location: Cincinnati, OH
Vehicle:
2004 Mitsubishi Evo
701whp 9.91@146

Default

Infamous - there are 5 wires on the MAF sensor and they all need to be extended. Be careful though as one of them is a shielded wire that must remain shielded in the extension wire. After we extended the wires, we put the MAF back in pre-turbo and started it and it ran perfectly, so we knew we wired it correctly.

Tony - so you piggybacked the stock MAP sensor signal off of the DTEC MAP sensor? The last picture I posted shows the wires inside the shield that go to the DTEC MAP sensor.
SloRice is offline   Reply With Quote
Old 07-27-2006, 02:03 PM   #6
x99percent
Scooby Specialist
 
Member#: 27108
Join Date: Oct 2002
Chapter/Region: MWSOC
Location: Detroit-ish, MI
Vehicle:
2004 STi
2004 A4

Default

Quote:
Originally Posted by SloRice
Tony - so you piggybacked the stock MAP sensor signal off of the DTEC MAP sensor?
No, what I was doing didn't involve a DTEC at all. I was splicing the signal from the stock MAP sensor... I was just saying that it seemed to work out OK. If you do something similar with the DTEC MAP sensor, both the DTEC and the ECU should get the same MAP signal voltage.


Quote:
Originally Posted by SloRice
The last picture I posted shows the wires inside the shield that go to the DTEC MAP sensor.
From the DTEC manual, it looks like the connector on the DTEC itself (goes to both BCS and MAP) is a 4-wire connector, but the connector further down the line that goes to just the MAP sensor is *also* a 4-wire connector. Odd.

If I had to guess.... the four wires at the DTEC are probably:
- power to MAP (probably 5V)
- ground for MAP
- signal from MAP
- BCS control signal (since the BCS has its own ground)

If you're going to splice into the wire at/near the MAP sensor, you can figure out which one is the signal wire with a voltmeter. Compare what you read at each wire when the key is "ON" with the engine running and not running.

From the service manual, it looks like the orange(?) wire at the factory MAP sensor is the signal wire. The other two are the power and ground for the factory sensor.
x99percent is offline   Reply With Quote
Old 07-27-2006, 02:21 PM   #7
SloRice
Scooby Specialist
 
Member#: 44351
Join Date: Sep 2003
Chapter/Region: MWSOC
Location: Cincinnati, OH
Vehicle:
2004 Mitsubishi Evo
701whp 9.91@146

Default

Quote:
Originally Posted by x99percent
No, what I was doing didn't involve a DTEC at all. I was splicing the signal from the stock MAP sensor... I was just saying that it seemed to work out OK. If you do something similar with the DTEC MAP sensor, both the DTEC and the ECU should get the same MAP signal voltage.
Your last sentence hit the nail on the head on what I want to do! Will the DTEC and ECU/UTEC get the same MAP signal voltage? Or will it get split between the two of them? I'm trying to remember back to my circuits class days.....if things are wired in parallel, they get the same voltage, right?

Quote:
Originally Posted by x99percent
From the DTEC manual, it looks like the connector on the DTEC itself (goes to both BCS and MAP) is a 4-wire connector, but the connector further down the line that goes to just the MAP sensor is *also* a 4-wire connector. Odd.

If I had to guess.... the four wires at the DTEC are probably:
- power to MAP (probably 5V)
- ground for MAP
- signal from MAP
- BCS control signal (since the BCS has its own ground)

If you're going to splice into the wire at/near the MAP sensor, you can figure out which one is the signal wire with a voltmeter. Compare what you read at each wire when the key is "ON" with the engine running and not running.

From the service manual, it looks like the orange(?) wire at the factory MAP sensor is the signal wire. The other two are the power and ground for the factory sensor.
I see what you are saying in the manual, I can't remember how many wires go to the BCS. I really didn't want to have to splice into every wire on the DTEC MAP harness to check voltages, but I guess I can if need be.

Yea, the 4 wire out of the DTEC to 4 wire split at the BCS/MAP split is odd also. The MAP has to get 5V from the DTEC, a signal wire back to the DTEC and a ground, which can either go back to the DTEC or into the BCS's ground. What's the 4th wire going to the MAP sensor then? Maybe a wire to supply signal voltage to the BCS? As for the BCS, it has it's own power and ground so those are out. I'd have to see how many wires are going to the BCS first to guess what they are.

As for the stock MAP sensor, I also believe the orange wire is the signal wire. Red and black are the power and ground. Again, I'll take a voltmeter to them to confirm.
SloRice is offline   Reply With Quote
Old 07-27-2006, 02:37 PM   #8
x99percent
Scooby Specialist
 
Member#: 27108
Join Date: Oct 2002
Chapter/Region: MWSOC
Location: Detroit-ish, MI
Vehicle:
2004 STi
2004 A4

Default

Quote:
Originally Posted by SloRice
Your last sentence hit the nail on the head on what I want to do! Will the DTEC and ECU/UTEC get the same MAP signal voltage? Or will it get split between the two of them? I'm trying to remember back to my circuits class days.....if things are wired in parallel, they get the same voltage, right?
They should get the same voltage. I believe it is the amperage that would be split.
x99percent is offline   Reply With Quote
Old 07-27-2006, 02:54 PM   #9
SloRice
Scooby Specialist
 
Member#: 44351
Join Date: Sep 2003
Chapter/Region: MWSOC
Location: Cincinnati, OH
Vehicle:
2004 Mitsubishi Evo
701whp 9.91@146

Default

what does that mean to me?
SloRice is offline   Reply With Quote
Old 07-27-2006, 02:55 PM   #10
x99percent
Scooby Specialist
 
Member#: 27108
Join Date: Oct 2002
Chapter/Region: MWSOC
Location: Detroit-ish, MI
Vehicle:
2004 STi
2004 A4

Default

Quote:
Originally Posted by SloRice
what does that mean to me?
Nothing!

All the DTEC and ECU care about is the voltage.
x99percent is offline   Reply With Quote
Old 07-27-2006, 03:16 PM   #11
SloRice
Scooby Specialist
 
Member#: 44351
Join Date: Sep 2003
Chapter/Region: MWSOC
Location: Cincinnati, OH
Vehicle:
2004 Mitsubishi Evo
701whp 9.91@146

Default

ok, next question. Do you know if the ECUtek program will allow me to go into the STI ECU and recalibrate the MAP sensor voltages?

i.e. stock MAP sensor - 5V=~22psi. I need to recalibrate it so that 5V = 4.5bar
SloRice is offline   Reply With Quote
Old 07-27-2006, 03:51 PM   #12
x99percent
Scooby Specialist
 
Member#: 27108
Join Date: Oct 2002
Chapter/Region: MWSOC
Location: Detroit-ish, MI
Vehicle:
2004 STi
2004 A4

Default

Quote:
Originally Posted by SloRice
ok, next question. Do you know if the ECUtek program will allow me to go into the STI ECU and recalibrate the MAP sensor voltages?

i.e. stock MAP sensor - 5V=~22psi. I need to recalibrate it so that 5V = 4.5bar
Hmm... a direct answer to your question is "I'm not sure". I don't see any MAP scale table in anything I've got.

An indirect answer is that it doesn't matter. The MAP sensor signal to the ECU is capped by your UTEC to whatever voltage corresponds to 12psi on a stock MAP sensor, plus the factory ECU doesn't use MAP for anything except for boost control (which you're not using) and a brief moment after a (cold?) start.
x99percent is offline   Reply With Quote
Old 07-27-2006, 03:55 PM   #13
SloRice
Scooby Specialist
 
Member#: 44351
Join Date: Sep 2003
Chapter/Region: MWSOC
Location: Cincinnati, OH
Vehicle:
2004 Mitsubishi Evo
701whp 9.91@146

Default

Why is it capped by the UTEC at 12psi? I don't understand this.

So according to what you are saying, I don't really care what the stock MAP sensor is doing and whether or not the ECU cares what it's doing.
SloRice is offline   Reply With Quote
Old 07-27-2006, 04:10 PM   #14
x99percent
Scooby Specialist
 
Member#: 27108
Join Date: Oct 2002
Chapter/Region: MWSOC
Location: Detroit-ish, MI
Vehicle:
2004 STi
2004 A4

Default

Quote:
Originally Posted by SloRice
Why is it capped by the UTEC at 12psi? I don't understand this.
That's the UTEC's FCD (fuel cut defender). A stock factory ECU will throw a CEL and limit boost if it sees 17psi for a few seconds.

Quote:
Originally Posted by SloRice
So according to what you are saying, I don't really care what the stock MAP sensor is doing and whether or not the ECU cares what it's doing.
As long as the factory ECU gets *a* signal, you don't really need to worry about *what* the signal is, provided that it's not causing an overboost CEL.
x99percent is offline   Reply With Quote
Old 07-27-2006, 04:39 PM   #15
SloRice
Scooby Specialist
 
Member#: 44351
Join Date: Sep 2003
Chapter/Region: MWSOC
Location: Cincinnati, OH
Vehicle:
2004 Mitsubishi Evo
701whp 9.91@146

Default

clear as mud!

j/k....sounds like I should be ok.
SloRice is offline   Reply With Quote
Old 07-27-2006, 09:31 PM   #16
tmarcel
Scooby Specialist
 
Member#: 7555
Join Date: Jun 2001
Chapter/Region: South East
Location: Charlotte NC
Default

Looking great, Tim! "You've Got Mail"

Todd
tmarcel is offline   Reply With Quote
Old 07-28-2006, 03:49 PM   #17
SloRice
Scooby Specialist
 
Member#: 44351
Join Date: Sep 2003
Chapter/Region: MWSOC
Location: Cincinnati, OH
Vehicle:
2004 Mitsubishi Evo
701whp 9.91@146

Default

Thanks Todd! I'm actually not at work today, but got my mail!
SloRice is offline   Reply With Quote
Old 07-28-2006, 03:50 PM   #18
SloRice
Scooby Specialist
 
Member#: 44351
Join Date: Sep 2003
Chapter/Region: MWSOC
Location: Cincinnati, OH
Vehicle:
2004 Mitsubishi Evo
701whp 9.91@146

Default

oh by the way...of the 4 wires in the last picture in my first post, two look the same color. One is blue and the other is green. The blue one is the signal wire.
SloRice is offline   Reply With Quote
Old 10-27-2006, 04:29 PM   #19
InfamousDX
Scooby Guru
 
Member#: 25413
Join Date: Sep 2002
Chapter/Region: Tri-State
Location: North NJ
Default

Quick question but what exactly is shielded wire (other than wire that's shielded)? Or rather, what does it look like compared to regular wire I would have used?
InfamousDX is offline   Reply With Quote
Old 10-27-2006, 09:03 PM   #20
tmarcel
Scooby Specialist
 
Member#: 7555
Join Date: Jun 2001
Chapter/Region: South East
Location: Charlotte NC
Default

Quote:
Originally Posted by InfamousDX View Post
Quick question but what exactly is shielded wire (other than wire that's shielded)? Or rather, what does it look like compared to regular wire I would have used?
It has a braided sleeve around the rest of the internal wire under the rubber outside. Hope that makes sense?
tmarcel is offline   Reply With Quote
Old 10-30-2006, 12:44 PM   #21
Bolster
Scooby Specialist
 
Member#: 22290
Join Date: Aug 2002
Chapter/Region: MAIC
Vehicle:
2002 WRB WRX Wagon

Default

Quote:
Originally Posted by tmarcel View Post
It has a braided sleeve around the rest of the internal wire under the rubber outside. Hope that makes sense?
Next question: So where do you get shielded wire to splice into and extend this wire?
Bolster is offline   Reply With Quote
Old 10-30-2006, 01:01 PM   #22
tmarcel
Scooby Specialist
 
Member#: 7555
Join Date: Jun 2001
Chapter/Region: South East
Location: Charlotte NC
Default

I got mine from Radio Shack when any other store would've been closed on a weekend. It was some type of Stereo cable and the package said shielded on it. I cut the ends off and cut the length that I needed. Stripped the ends back and spliced it in. The shield, which is the braided part needs to be twisted up with the original MAF wire shield. Then wrap everything together and use some type of wire cover to protect all the wires and make it look professional
tmarcel is offline   Reply With Quote
Old 10-30-2006, 11:08 PM   #23
Bolster
Scooby Specialist
 
Member#: 22290
Join Date: Aug 2002
Chapter/Region: MAIC
Vehicle:
2002 WRB WRX Wagon

Default

Quote:
Originally Posted by tmarcel View Post
I got mine from Radio Shack when any other store would've been closed on a weekend. It was some type of Stereo cable and the package said shielded on it. I cut the ends off and cut the length that I needed. Stripped the ends back and spliced it in. The shield, which is the braided part needs to be twisted up with the original MAF wire shield. Then wrap everything together and use some type of wire cover to protect all the wires and make it look professional
Thanks! This may be my next mod.
Bolster is offline   Reply With Quote
Old 11-09-2006, 09:25 AM   #24
SloRice
Scooby Specialist
 
Member#: 44351
Join Date: Sep 2003
Chapter/Region: MWSOC
Location: Cincinnati, OH
Vehicle:
2004 Mitsubishi Evo
701whp 9.91@146

Default

Quick update on this. Blow through MAF setup is still working great.

But how I originally planned on dealing with the MAP sensor didn't work. I ended up leaving the DTEC MAP sensor alone. Bought a new TurboXS MAP sensor and cut the wires going into the UTEC from the stock MAP sensor and wired in the new TXS one. Then I made a jumper wire from the stock MAP sensor, around the UTEC and to the ECU. So the UTEC now get's a 4.5bar map sensor and the ECU gets the stock map sensor and everyone is happy.

To power the TurboXS MAP sensor, you need to splice into the stock MAP sensor's power wire as they both run on 5V, not 12V. Then just ground the TurboXS MAP sensor's ground wire to the chassis.
SloRice is offline   Reply With Quote
Old 11-09-2006, 01:42 PM   #25
tazswing
Scooby Specialist
 
Member#: 63767
Join Date: Jun 2004
Chapter/Region: NWIC
Location: PDX
Vehicle:
2009 OXT 5-spd
2011 STi hatch

Default

wow, neat stuff. and to think that I am still trying to get my DTEC settings worked out!!!
tazswing is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
cold weather and speed density qwkwrx UTEC 5 01-23-2010 12:08 PM
utec, speed density, and misfire codes MRX WRX UTEC 240 06-16-2009 11:31 AM
UTEC Speed Density Tuning How-To? Zumble UTEC 2 02-10-2007 03:16 PM
Utec Delta with Speed density 437whp on pump 91 AZScoobie Proven Power Bragging 39 09-26-2006 09:05 PM
Switched to Blow-thru and Speed-density via 5.8, pics inside NavyBlueSubaru UTEC 25 08-13-2006 04:07 PM


All times are GMT -4. The time now is 02:19 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.