Go Back   MustangForums.com > Ford Mustang Tech > 4.6L (1996-2004 Modular) Mustang
Sign in using an external account
Register Forgot Password?
Search


4.6L (1996-2004 Modular) Mustang Technical discussions on 1996-2004 4.6 Liter Modular Motors (2V and 4V) within.
Sponsored by Cruizin Concepts


Welcome to Mustang Forums!
Welcome to Mustang Forums.

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, at no cost, 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!


Reply
 
 
 
 
Thread Tools Search this Thread
Old 03-02-2010, 06:49 PM   #11
Stevecooper
3rd Gear Member
 
Join Date: Aug 2008
Location: Oklahoma
Posts: 912
Default

Quote:
Originally Posted by Chris98Gt View Post
Check out the spreadsheet is that the transfer function that I'm looking for?
http://www.vmptuning.com/store/index...=193&parent=30
You will have to wait for Cliffy, in the SCT software that is what you would need. I am not that familiar with snipers software packages.
This ad is not displayed to registered or logged-in members.
Register your free account today and become a member on Mustang Forums!
__________________
2001 Bullitt
281CI Blue Printed Engine (Teksid, CP's, Manley Billit, Cobra Crank,) Foxlake Ported SVO heads, PI CAM's, kooks LT's, 2.3L Allen Twin Screw Blower, 63lb, SCT2800 MAF, Mcloed 8" Twin disk, Viper T-56, Griggs GR40 With Watt Link. SSR GT3's... and more. Tuned by... Me.
535HP, 530TQ 12PSI .
Stevecooper is offline   Reply With Quote
Old 03-02-2010, 07:10 PM   #12
cliffyk
TECH SAVANT
 
cliffyk's Avatar
 
Join Date: Dec 2006
Vehicle: 1998 SL500
Location: Saint Augustine, FL
Posts: 10,910
Default

Quote:
Originally Posted by Chris98Gt View Post
If the maf in question has the same transfer function as the stock 05 style mafs would that work if I bought the hpx maf and selected a stock 05 style maf?
Not likely...

The actual sensor in a MAF mesasures only a small sample of the air actually passing through the MAF housing--that value is converted to a voltage and sent to the PCM where it looks up that volage in a table (the MAF transfer function) and says "Ah-Ha", "X" kg/h of air is coming in.

For example, with the stock 80mm MAF on my '03 the actual flow area of the sensor is about 64mm˛ and the total flow area of the MAF housing is 3994mm˛--so the ratio between the total flow and the sampled flow is 3994/64 or 0.016 or 62:1 or so.

If I stick that same sensor in a 90mm housing (5450mm˛ total area) then the ratio of the total flow area to the sample flow area will be 5450/64 or 85:1. I.e. 37% (85/62) more air is coming in--but the PCM doesn't know this as it's still using the old transfer function. The result will be a VERY lean mix...

This is why on the '05 and later Mustangs changing the intake plumbing almost always requires a tune. The MAF sensor is mounted into the intake in such a way the the after market intakes ("CAIs") have to built with new MAF housings. If these new housings do not have the same flow characteristics as the OEM housing then the transfer function is screwed up.

This brings up an interesting issue regarding using an '05 sensor in a 75 mm housing. I have no idea what size the '05 MAF housing is, however I assume it's as big or bigger than the 80mm (3994mm˛) housing used on our cars.

Assuming it's 80mm diameter, placing that sensor in a 75 mm housing (3510mm˛) will reduce the total flow area/sensor flow area ratio to 55:1 from the 62:1 of the 80mm housing. this means that if using the stock transfer function the PCM will believe that 12% more air is entering than really is, and will adjust the fueling for that additional aiir--BUT that air isn't really flowing so the mix will be 12% rich.

This then leads to "Why would you want to replace an 80mm MAF housing [stock] with a 75mm housing"--regardless of whether the sensor's signal can be properly mapped by the PCM, a 75mm hole (3510mm˛) will be more restrictive than an 80mm hole (3994mm˛).

Frankly that 75mm VPM housing is a mystery to me, there are several OEM MAF sensors much larger than that, and they brag about the 3" inlet and outlet as though that were some wonderous thing. The inlet and outlet of the OEM MAF on a new-edge 'stang are 3.4" (87mm), almost 35% larger by flow area...
__________________
-cliff knight-
SOLD! - 2003 GT, UPR X, FRPP 24lb/h, Magnaflow, PP 70mm TB & plenum,
Delta Force tuned, Steeda UDPs, Ralco flywheel,
RAM HDX clutch, 3.73s, 262 rwHP/305 lb-ft.

New ride (7/1/2013) 1998 Mercedes SL500-5.0L 32V VVT 326/347 HP/tq


Engineering is, at its base, making what you want from what you have.
At its extreme it is making what you want from what you can get.
cliffyk is offline   Reply With Quote
Old 03-02-2010, 07:21 PM   #13
cliffyk
TECH SAVANT
 
cliffyk's Avatar
 
Join Date: Dec 2006
Vehicle: 1998 SL500
Location: Saint Augustine, FL
Posts: 10,910
Default

Oh, there is one other issue...

The EEC-V PCM used in our cars has an internal airflow limit of approximately 1700kg/h (3740lb/h). Running n/a @ 12.5:1 AFR this is good for 600 or so crank HP, running f/i at 11.5:1 it's 540 fwHP or so.

When you beyond this limit it is necessary to rescale the air charge scalar, and a few other values. SF does this automatically when a MAF flowing more than 1700kg/h is selected.

Here are the transfer functions of a few "MAFs I have known":
Click the image to open in full size.
__________________
-cliff knight-
SOLD! - 2003 GT, UPR X, FRPP 24lb/h, Magnaflow, PP 70mm TB & plenum,
Delta Force tuned, Steeda UDPs, Ralco flywheel,
RAM HDX clutch, 3.73s, 262 rwHP/305 lb-ft.

New ride (7/1/2013) 1998 Mercedes SL500-5.0L 32V VVT 326/347 HP/tq


Engineering is, at its base, making what you want from what you have.
At its extreme it is making what you want from what you can get.
cliffyk is offline   Reply With Quote
Old 03-02-2010, 07:32 PM   #14
Stevecooper
3rd Gear Member
 
Join Date: Aug 2008
Location: Oklahoma
Posts: 912
Default

Quote:
Originally Posted by cliffyk View Post
Oh, there is one other issue...

The EEC-V PCM used in our cars has an internal airflow limit of approximately 1700kg/h (3740lb/h). Running n/a @ 12.5:1 AFR this is good for 600 or so crank HP, running f/i at 11.5:1 it's 540 fwHP or so.

When you beyond this limit it is necessary to rescale the air charge scalar, and a few other values. SF does this automatically when a MAF flowing more than 1700kg/h is selected.

Here are the transfer functions of a few "MAFs I have known":
Click the image to open in full size.

Really? I thought this only affected certain processor codes. I know the 03/04 cobras have this issue, as does the 04 Lightnings and all Ford GT's. You can see in this SCT software that the TF is read in Lb per min but if you multiple by 60 you can see that the TF can go far beyond 3740lb/h. In the SCT software we see this problem on the affected processors around 64Lb/min which would be really close to your 3740lb/h

Click the image to open in full size.
__________________
2001 Bullitt
281CI Blue Printed Engine (Teksid, CP's, Manley Billit, Cobra Crank,) Foxlake Ported SVO heads, PI CAM's, kooks LT's, 2.3L Allen Twin Screw Blower, 63lb, SCT2800 MAF, Mcloed 8" Twin disk, Viper T-56, Griggs GR40 With Watt Link. SSR GT3's... and more. Tuned by... Me.
535HP, 530TQ 12PSI .
Stevecooper is offline   Reply With Quote
Old 03-02-2010, 07:46 PM   #15
cliffyk
TECH SAVANT
 
cliffyk's Avatar
 
Join Date: Dec 2006
Vehicle: 1998 SL500
Location: Saint Augustine, FL
Posts: 10,910
Default

Quote:
Originally Posted by Stevecooper View Post
Really? I thought this only affected certain processor codes. I know the 03/04 cobras have this issue, as does the 04 Lightnings and all Ford GT's. You can see in this SCT software that the TF is read in Lb per min but if you multiple by 60 you can see that the TF can go far beyond 3740lb/h. In the SCT software we see this problem on the affected processors around 64Lb/min which would be really close to your 3740lb/h
AFAIK, all new-edge Mustang GT box codes have this issue, not that I have examined them all. It is a template driven issue in Special Forces, however I have not yet run in to a new-edge template that is differently configured.

As to the TF entries, you can enter whatever you like in the transfer function, it's just that the PCM will ignore any values greater then 1700kg/h. This is well documented in the Ford specific section of Greg Banish's book Engine Management:Advanced Tuning.
__________________
-cliff knight-
SOLD! - 2003 GT, UPR X, FRPP 24lb/h, Magnaflow, PP 70mm TB & plenum,
Delta Force tuned, Steeda UDPs, Ralco flywheel,
RAM HDX clutch, 3.73s, 262 rwHP/305 lb-ft.

New ride (7/1/2013) 1998 Mercedes SL500-5.0L 32V VVT 326/347 HP/tq


Engineering is, at its base, making what you want from what you have.
At its extreme it is making what you want from what you can get.

Last edited by cliffyk; 03-02-2010 at 07:49 PM.
cliffyk is offline   Reply With Quote
Old 03-02-2010, 07:51 PM   #16
Chris98Gt
3rd Gear Member
 
Chris98Gt's Avatar
 
Join Date: Apr 2007
Vehicle: 98 Mustang Gt
Location: Georgia
Posts: 931
Default

Was that not the transfer function tables I needed in the link I posted?
you have to click on the link that says HPX tool.xls spreadsheet <----- or this one apparently works lol.
__________________

98 Turbo GT

Last edited by Chris98Gt; 03-02-2010 at 07:53 PM.
Chris98Gt is offline   Reply With Quote
Old 03-02-2010, 07:58 PM   #17
Stevecooper
3rd Gear Member
 
Join Date: Aug 2008
Location: Oklahoma
Posts: 912
Default

Quote:
Originally Posted by cliffyk View Post
AFAIK, all new-edge Mustang GT box codes have this issue, not that I have examined them all. It is a template driven issue in Special Forces, however I have not yet run in to a new-edge template that is differently configured.

As to the TF entries, you can enter whatever you like in the transfer function, it's just that the PCM will ignore any values greater then 1700kg/h. This is well documented in the Ford specific section of Greg Banish's book Engine Management:Advanced Tuning.
I have both of his books, I will check it out when I get home from work. I thought the book pointed to the fact that this affects only some of the computers out there. One that it mentions it the Ford GT where even at the OE level they are scaling to make it work.

In the SCT software on vehicles I have worked with you can not enter a value higher than 63.xlb/min if the processor is incapable of reading the value. Either way I'll check it out tonight.

Steve.
__________________
2001 Bullitt
281CI Blue Printed Engine (Teksid, CP's, Manley Billit, Cobra Crank,) Foxlake Ported SVO heads, PI CAM's, kooks LT's, 2.3L Allen Twin Screw Blower, 63lb, SCT2800 MAF, Mcloed 8" Twin disk, Viper T-56, Griggs GR40 With Watt Link. SSR GT3's... and more. Tuned by... Me.
535HP, 530TQ 12PSI .
Stevecooper is offline   Reply With Quote
Old 03-02-2010, 08:06 PM   #18
cliffyk
TECH SAVANT
 
cliffyk's Avatar
 
Join Date: Dec 2006
Vehicle: 1998 SL500
Location: Saint Augustine, FL
Posts: 10,910
Default

Quote:
Originally Posted by Chris98Gt View Post
Was that not the transfer function tables I needed in the link I posted?
you have to click on the link that says HPX tool.xls spreadsheet
The worksheet generates what appears to be a valid a 30-point transfer function for that sensor, the PMAS HPX, in a given tube. No units for the air flow are given.

However on the intro page the comment "In some cases you may need to convert volts to counts or kg/hr to lb/min." is made leading me to believe that the air flow units are lb/h--which makes sense looking at the values.

Meaning that the air flow for the HPX sensor in the 75mm housing, at 5.0V output from the MAF (2650 lb/h), will be quite a bit less than that of the stock 80mm MAF on my '03 GT at 5.0V (a bit over 3000 lb/h).
__________________
-cliff knight-
SOLD! - 2003 GT, UPR X, FRPP 24lb/h, Magnaflow, PP 70mm TB & plenum,
Delta Force tuned, Steeda UDPs, Ralco flywheel,
RAM HDX clutch, 3.73s, 262 rwHP/305 lb-ft.

New ride (7/1/2013) 1998 Mercedes SL500-5.0L 32V VVT 326/347 HP/tq


Engineering is, at its base, making what you want from what you have.
At its extreme it is making what you want from what you can get.

Last edited by cliffyk; 02-02-2013 at 02:12 AM.
cliffyk is offline   Reply With Quote
Old 03-02-2010, 08:17 PM   #19
cliffyk
TECH SAVANT
 
cliffyk's Avatar
 
Join Date: Dec 2006
Vehicle: 1998 SL500
Location: Saint Augustine, FL
Posts: 10,910
Default

Quote:
Originally Posted by Stevecooper View Post
I have both of his books, I will check it out when I get home from work. I thought the book pointed to the fact that this affects only some of the computers out there. One that it mentions it the Ford GT where even at the OE level they are scaling to make it work.

In the SCT software on vehicles I have worked with you can not enter a value higher than 63.xlb/min if the processor is incapable of reading the value. Either way I'll check it out tonight.

Steve.
Appendix A. page 110...and I think you are correct as he says it affects only 2002+ EEC-V PCMs.

I just looked at a 2000 MY Special Forces template and found that the >1700 kg/h scaling indicator is not set...
__________________
-cliff knight-
SOLD! - 2003 GT, UPR X, FRPP 24lb/h, Magnaflow, PP 70mm TB & plenum,
Delta Force tuned, Steeda UDPs, Ralco flywheel,
RAM HDX clutch, 3.73s, 262 rwHP/305 lb-ft.

New ride (7/1/2013) 1998 Mercedes SL500-5.0L 32V VVT 326/347 HP/tq


Engineering is, at its base, making what you want from what you have.
At its extreme it is making what you want from what you can get.
cliffyk is offline   Reply With Quote
Old 03-02-2010, 08:24 PM   #20
Chris98Gt
3rd Gear Member
 
Chris98Gt's Avatar
 
Join Date: Apr 2007
Vehicle: 98 Mustang Gt
Location: Georgia
Posts: 931
Default

It also says that it's a direct bolt in for the 05+, would that not lead you to think that it has the same transfer function as the stock 05+, or do you think they just mean that it will bolt in, but still need tuning.
__________________

98 Turbo GT
Chris98Gt is offline   Reply With Quote
Old 03-02-2010, 08:24 PM
MustangForums
Ford Mustang




Paid Advertisement

 
 
 
Reply

Tags
44, 75mm, delta, deltaforcetuning, force, gm, hack, hpx, lbmin, maf, sct, sniper, software, spreadsheet, tuning

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Forum Jump

Advertising

Featured Sponsors
Vendor Directory
New Sponsors
All times are GMT -5. The time now is 12:09 PM.

© Internet Brands, Inc.


This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. Ford® is a registered trademark of the Ford Motor Company
Emails Backup