Welcome to the North American Subaru Impreza Owners Club Tuesday September 16, 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 > Open Source Reflashes

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 11-08-2011, 04:51 AM   #1
Merp
*** Banned ***
 
Member#: 199106
Join Date: Jan 2009
Location: Pennsyltucky
Vehicle:
PMme 4 Speed Density
Patches on OEM ECU

Default Open Source Speed Density Patches

Hey guys, just wanted to give you a heads up, I am working on speed density patches for 32bit ecu's.

The 06/07 USDM WRX MT rom is currently the only rom available, but STi roms are in the works. I will update this thread as they roll out.

To request a particular rom to be patched, send me a pm or donation through the link.

RomRaider • View topic - Speed Density ROM - A8DH201X 2006/2007 WRX

Thanks!
* Registered users of the site do not see these ads.
Merp is offline   Reply With Quote
Old 11-08-2011, 09:54 AM   #2
aeonflux99
Scooby Newbie
 
Member#: 54832
Join Date: Feb 2004
Chapter/Region: E. Canada
Location: Canada
Vehicle:
2006 WRX
Blue

Default

Awesome!
aeonflux99 is offline   Reply With Quote
Old 11-10-2011, 02:39 PM   #3
scoobtube
Scooby Newbie
 
Member#: 298777
Join Date: Oct 2011
Default

What's the difference between speed density tuning and mass airflow tuning? Does anyone have any good links on the topic? In other words why would you want to change to speed density tuning?
scoobtube is offline   Reply With Quote
Old 11-10-2011, 03:10 PM   #4
sorrowfulkiller
Scooby Specialist
 
Member#: 170439
Join Date: Jan 2008
Location: Sioux Falls, SD
Vehicle:
I <3 Lamp

Default

MAF tuning is finnicky when you start to get away from stock intake size, not only that but you can't upgrade your MAF sensor, hence you start to get to the point that you are maxing out the sensor and can't make any more power because of that. Not only that but with high horsepower maf cars daily driveability suffers, where a speed density tuned car can just go up to a larger map sensor and still have near the same amount of driveability.
sorrowfulkiller is offline   Reply With Quote
Old 11-10-2011, 05:57 PM   #5
scoobtube
Scooby Newbie
 
Member#: 298777
Join Date: Oct 2011
Default

Can you still pass emissions once running speed density?
scoobtube is offline   Reply With Quote
Old 11-10-2011, 06:01 PM   #6
scoobtube
Scooby Newbie
 
Member#: 298777
Join Date: Oct 2011
Default

at what point does the factory maf tap out? Since this is about open source tuning using the factory ecu, would you pass emissions switching to speed density?
scoobtube is offline   Reply With Quote
Old 11-10-2011, 06:05 PM   #7
scoobtube
Scooby Newbie
 
Member#: 298777
Join Date: Oct 2011
Default

At what point does the factory maf tap out? Since this is about open source tuning using the factory ecu, would you pass emissions switching to speed density?

found a good link on the subject i believe:

http://ls1tech.com/forums/pcm-diagno...d-density.html
scoobtube is offline   Reply With Quote
Old 11-10-2011, 06:27 PM   #8
Merp
*** Banned ***
 
Member#: 199106
Join Date: Jan 2009
Location: Pennsyltucky
Vehicle:
PMme 4 Speed Density
Patches on OEM ECU

Default

I've never maxed a factory, but my old APS 70mm (stock is 65mm) was getting very close around 400whp.

This speed density simply replicates the MAF output using an algorithm, when tuned properly, it will pass emissions.
Merp is offline   Reply With Quote
Old 11-11-2011, 03:34 PM   #9
D0nets
Scooby Newbie
 
Member#: 129746
Join Date: Oct 2006
Location: West TN
Vehicle:
2007 stg3 WRX
WR Blue

Default

Very nice, I will give this a shot. As far as maxing the maf goes, I am just at the point of maxing mine on my 07 wrx with an aps 65mm intake, gimmick inlet and aftermaf, vf39, and catless tbe. When it gets cold, I am hitting 4.7 volts. The maf table max shows 4.69 volts.
D0nets is offline   Reply With Quote
Old 12-18-2011, 04:21 PM   #10
mecpgh
Scooby Newbie
 
Member#: 193014
Join Date: Oct 2008
Location: Charleston, SC
Vehicle:
02 WRX WRB, 05 STI
FPGreen E85 400+whp

Default

Bump for this thread. Ready to test one for 05sti rom but I'm no software engineer. Hoping you guys are going to do patches because I'm site I would have no trouble selling it with my tunes locally.
mecpgh is offline   Reply With Quote
Old 12-19-2011, 04:37 PM   #11
aeonflux99
Scooby Newbie
 
Member#: 54832
Join Date: Feb 2004
Chapter/Region: E. Canada
Location: Canada
Vehicle:
2006 WRX
Blue

Default

APS 70mm intake and it's showing a peak of 4.59 volts. So I might be very interested in giving this a try as well. That said my daily drivability is still pretty decent, despite how much AF learning at idle I end up with.
aeonflux99 is offline   Reply With Quote
Old 12-19-2011, 05:31 PM   #12
eminehart
Scooby Newbie
 
Member#: 11205
Join Date: Oct 2001
Chapter/Region: RMIC
Location: Tweakin your ECU-Northglenn CO
Vehicle:
2009 WRX
Dom3-e85-ewg

Default

There are advantages and disadvantages to each system.

Speed density systems tend to be a little better for higher powered cars where large maf housings would otherwise be needed. With the larger maf housing there is always a sacrifice of resolution and consistency. Speed density is almost required for most rotated turbo systems since they cause a lot of turbulence at the maf. Also Atmospheric BOV's can be used without any negative effects. And things like Boost leaks will not change your AFR's.
For a speed density car, any mod that helps flow more efficiently like headers or exhaust will change the VE and the car will need to be retuned. Even something as small as changing out the exhaust could potentially cause issues. In these circumstances a freer flowing modification (adding a dp) will cause the car to run rich and a restrictive change (adding a cat) will cause the car to run lean.
Many speed density systems do not handle atmospheric pressure changes well so if you regularly drive up and down in large elevations then you will not get the best performance out of the car. A nice standalone with MAP/(Barometric pressure) system for determining VE is probably necessary. A system like this one or Cobb's Speed density(available via protune) is not up to this task.

The advantage to MAF is that it takes VE completely out of the equation so it handles elevation changes better as well as mods(other than the intake system), without needing to be retuned as thoroughly. Changing out exhaust, cams, intake manifold and turbos should not effect the AFR's as the increase in airflow or VE is measured at the MAF and accounted for as long as the car is properly tuned.

The move to a speed density system of any kind(reflash or standalone) is a decision you will have to weigh carefully for your needs. For most people if you aren't having issues with your MAF based tune the move to speed density is not really needed.
eminehart is offline   Reply With Quote
Old 12-19-2011, 10:27 PM   #13
NSFW
Scooby Guru
 
Member#: 140444
Join Date: Feb 2007
Chapter/Region: NWIC
Location: Near Seattle, WA
Vehicle:
05 Stage Free LGT
ATP 3076, 6MT, AVO FMIC

Default

Quote:
Originally Posted by eminehart View Post
A nice standalone with MAP/(Barometric pressure) system for determining VE is probably necessary. A system like this one or Cobb's Speed density(available via protune) is not up to this task.
It would not be too hard to add a barometric pressure compensation to the open source speed density patches. Is 4000 feet of elevation change enough to make a measurable difference in AFR? If so I'll be able to study this in a couple weeks when I get SD on my car and go snowboarding. If you have a rough idea of how much that should change the mixture, that would be helpful.

Thanks!
NSFW 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
UTEC, DTEC and Speed Density SloRice UTEC 26 03-21-2007 01:26 PM
Speed Density on my Car this morning.. AZScoobie UTEC 42 09-18-2006 01:33 PM
New Speed Density, ver 5.8 FW is out! tmarcel UTEC 13 08-02-2006 05:20 PM
PCV on WRX with Speed Density Token-Negro Built Motor Discussion 3 07-21-2006 10:26 AM
please ASAP is the STI speed density or mass air bobturismo Off-Topic 12 04-25-2004 02:45 PM


All times are GMT -4. The time now is 04:46 PM.


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.