Fuel PSI , Boost-A-Pump , Fuel PSI issues - Focus Fanatics
Ford Focus Forum
HomeContact UsAbout UsGalleryDiscussion ForumsMarketplace



Go Back   Focus Fanatics > Ford Focus Tech Discussions > General Forced Induction

General Forced Induction The place to chat about turbochargers, superchargers nitrous systems and custom engine fabrications.

Search This Forum | Image Search | Advanced Search    
FocusFest Ford Focus Tire & Wheels FocusFanatics Merchandise

Reply
 
Thread Tools Display Modes
Old 04-19-2007, 04:23 PM   #1
1turbofocus
FF Affiliate
 
1turbofocus's Avatar
 
Join Date: Oct 2003
Fan#: 1123
Location: Belmont, NC
What I Drive: 2000 ZX3 / 2002 SVT Turbocharged

Posts: 21,484
FF Reputation: 153 1turbofocus Excellent Standing Member1turbofocus Excellent Standing Member
Buy-Sell-Trade Rating: (28)
Fuel PSI , Boost-A-Pump , Fuel PSI issues

I have spent a lot of time the last 2 days playing with fuel PSI on a 350HP Focus

Issues are fuel PSI dropping to 23psi at 4800 and 22psi , Focus has 72lb Inj and AF is holding but the injectors are maxed out because of the low fuel psi

The way the injector dutycycle works is as the fuel psi goes down the Inj dutycycle goes up to allow for and to maintain the targeted AF

Added a boost-a-pump voltage to the pump went from 13.3 to 17.6 and fuel PSI went to 32psi , still not enough

I have said all along that the fuel pump is run off the ground wire and not the Pos wire , that is why hooking up the boost-a-pump did little to help this problem

The ideal psi is 1psi to each psi of boost 1 to 1 ratio so with 22psi boost we need 62psi fuel psi to safely run this at 350HP

I called and spent about 3 Hrs on the Phone on and off the last 2 days with Kenny Bell maker of the BAP , what they came down to was either the lines from the pump to the fuel rail were not large enough or it was a low amp. problem and the wires were not large enough to carry the load of the pump

Ok fair enough , ran all new large wiring from the Batt to the pump driver both - and + wires , No help with fuel PSI

I wanted to test and see what would happen if the ground wire went straight to ground ( NO BAP ) so i connected a wire to the ground to the pump and had 80psi fuel psi , S W E E T problem solved or so i thought , did a run with the ground and fuel psi went to 37psi, Hmmm slightly better but still not good enough
So i hooked the BAP up with the ground wire grounded and it fell to 54.6PSI and stayed there did 2 or 3 runs to back this up and she held perfect at 54,55PSI each run , this told me 2 things , 1) that the fuel pump , lines , filter , fuel rail were all large enough to do the job , 2) That it is a ECU controle meaning in the Diablo/SCT software there not giving us enough fuel pump controles or a design problem that cannot be controled with the ECU because the ground wire never goes above 7 volts at 100% pump dutycycle and fuel PSI at 23psi and it needs to go to 12 or 13 volts (full ground) ground

Now the problem and where im hoping some one out there knows or works for an electronics place , I need some type of switch that as boost comes on it can raise voltage , if i can get the ground to come on at say 10psi then go up as boost goes up I "think" i can cure our low fuel PSI issues

This piece/part needs to be able to hold about 6 amps and as high as 30psi

Any ideas ?

Tom


__________________
Focus-Power: Your #1 Source for Ford Focus Speed, Tuning & Performance!

Customer Support
AIM: hpdyno
Email: hpdyno@aol.com
Phone: 704-249-3745
Site: focus-power.com

Elder 1turbofocus
1turbofocus is offline  
    Reply With Quote
Sponsored Links
Advertisement
 
Old 04-19-2007, 05:16 PM   #2
Pitch Black216
Focus Enthusiast
 
Join Date: Mar 2005
Fan#: 20367
Location: Orono, MN
What I Drive: pitch black focus

Posts: 199
FF Reputation: 3 Pitch Black216 Good Standing Member
Buy-Sell-Trade Rating: (0)
if you could get that to work that would be awesome!!
__________________
Pitch Black Euro Focus

Rieger Kit, 18" Superleggeras, Full Alpine System, Built CGI Block/Head, T3/T4 CBB Turbo, 300.17 HP
January 2007 FF ROTM / June 2007 FJ ROTM
Pitch Black216 is offline  
    Reply With Quote
Old 04-19-2007, 06:20 PM   #3
03OrangeSVT
LETS TURN DIRT!!!!
 
03OrangeSVT's Avatar
 
Join Date: Feb 2005
Fan#: 19169
Location: Piketon, OH
What I Drive: MINI Cooper S TURBO

Posts: 11,906
FF Reputation: 152 03OrangeSVT Excellent Standing Member03OrangeSVT Excellent Standing Member
Buy-Sell-Trade Rating: (5)
Very interesting..... but you knew I would say that didnt you...

What if you used the pressure activation switch off of a BAP for the ground switch??
__________________
[B]1951 McCormick FARMALL M
2007 MINI Cooper S Turbo... new project car
1998 Chevy 3500 Ext cab, long bed, 4x4, duelly, turbo diesel
2004 Harley V-Rod.... sex on wheels
2011 Harley Electra Glide Ultra Limited
[/b]
03OrangeSVT is offline  
    Reply With Quote
Old 04-19-2007, 06:33 PM   #4
1turbofocus
FF Affiliate
 
1turbofocus's Avatar
 
Join Date: Oct 2003
Fan#: 1123
Location: Belmont, NC
What I Drive: 2000 ZX3 / 2002 SVT Turbocharged

Posts: 21,484
FF Reputation: 153 1turbofocus Excellent Standing Member1turbofocus Excellent Standing Member
Buy-Sell-Trade Rating: (28)
The BAP switch comes on full at 3 - 5psi depending on what kit you have , I need something that comes on with boost and not all at one time

Tom
__________________
Focus-Power: Your #1 Source for Ford Focus Speed, Tuning & Performance!

Customer Support
AIM: hpdyno
Email: hpdyno@aol.com
Phone: 704-249-3745
Site: focus-power.com

Elder 1turbofocus
1turbofocus is offline  
    Reply With Quote
Old 04-19-2007, 06:46 PM   #5
SVTF4243
Focus Addict
 
SVTF4243's Avatar
 
Join Date: Feb 2004
Fan#: 4068
Location: Pasadena, CA
What I Drive: SVT 2002

Posts: 710
FF Reputation: 11 SVTF4243 Great Standing Member
Buy-Sell-Trade Rating: (1)
A naive-way-off-from-left-field thought:
Would hypergrounding help?
__________________
Silver SVT 2002 svtf4243.com
Silver ST3 MR::: 02 11 2013
GO :: Cobb RRM | Accelerator petal mod| JBR OCC | STS | Springs| Rear Swaybar | Tune
SHOW :: Lights tint | Calipers Painted| Graphite colored wheels| Back up Cam | Window Tint
SVTF4243 is offline  
    Reply With Quote
Old 04-19-2007, 08:17 PM   #6
1turbofocus
FF Affiliate
 
1turbofocus's Avatar
 
Join Date: Oct 2003
Fan#: 1123
Location: Belmont, NC
What I Drive: 2000 ZX3 / 2002 SVT Turbocharged

Posts: 21,484
FF Reputation: 153 1turbofocus Excellent Standing Member1turbofocus Excellent Standing Member
Buy-Sell-Trade Rating: (28)
No hypergrounding wouldnt help , The problem isnt a ground issue , the problem is how the ground is controled through the ECU , The Fuel Pump dutycycle is controled through the ground by the ECU

Tom
__________________
Focus-Power: Your #1 Source for Ford Focus Speed, Tuning & Performance!

Customer Support
AIM: hpdyno
Email: hpdyno@aol.com
Phone: 704-249-3745
Site: focus-power.com

Elder 1turbofocus
1turbofocus is offline  
    Reply With Quote
Old 04-19-2007, 08:31 PM   #7
v8focus1
Focus Enthusiast
 
v8focus1's Avatar
 
Join Date: Jan 2004
Fan#: 2562
Location: Fort Ashby,WV, United States
What I Drive: 2002 PW Focus SVT Malibu Blue

Posts: 81
FF Reputation: 20 v8focus1 Great Standing Member
Buy-Sell-Trade Rating: (1)
Is the fuel driver module, fuel pressure sensor all reading right? What if a problem in one of those is throwing off the other. The FRP sensor senses a difference in manifold pressure and fuel pressure- either side could be causing a problem.
MSD has a driver type module (MSD-8966 from summit racing)that you can base off a MAP sensor-you can control the on/off points based off sensor voltage.
__________________
Ian Saville-Modification Specialist/teacher
2000 Zx3 SHOcus(Yolk)(3.0L DOHC SHO swap)
2002 Zx3 PW BBK SVT engine/trans swap(Malibu Blue)
260hp, 213tq thanks to McNews
v8focus1 is offline  
    Reply With Quote
Old 04-19-2007, 08:50 PM   #8
cwczx3
Focus Addict
 
cwczx3's Avatar
 
Join Date: Sep 2003
Fan#: 852
Location: York, PA 17404, United States
What I Drive: 2000 Autumn orange ZX3

Posts: 565
FF Reputation: 5 cwczx3 Good Standing Member
Buy-Sell-Trade Rating: (4)
Very nice work Tom glad to see your still developing and tuning in the Focus world. I lurk more than i post but i highly value your opinions and follow all your posts to keep up with what you have figured out lately, goood info and keep it coming.
__________________
2000 Autumn Orange ZX3 "Beauty"Weekend Toy
2013 Performance Blue STDaily
2001 Flat Black ZX3 "River Rat"SOLD
cwczx3 is offline  
    Reply With Quote
Old 04-19-2007, 09:10 PM   #9
Damage
Focus Enthusiast
 
Join Date: Jul 2004
Fan#: 10682
Location: Central, NJ
What I Drive: 04 ZX3

Posts: 305
FF Reputation: 5 Damage Good Standing Member
Buy-Sell-Trade Rating: (7)
Tom I was looking through some stuff here as far as different types of pneumatic switches. I was thinking of a switch/relay setup. But I was wondering are you looking for something that allows the ECU to control the ground until a set psi.....and then lets say 15psi is when you want to take over..do you want a full ground or are you wanting to alter it as the boost continues to rise above 15psi(made up #)? Also is the reason the ECU isnt giving you the ability to change the voltage drop across the pump(to give it a "full ground"). Because It would eventually burn up the pump or the fuel pump driver in the ECU(If it is in the ECU..I have never worked on this part of the focus) if it was wired to give it a full ground. Let me know if I can help. I can also make a schematic if you would like something drawn up.

Last edited by Damage; 04-19-2007 at 11:06 PM.
Damage is offline  
    Reply With Quote
Old 04-19-2007, 11:00 PM   #10
99dot
Focus Enthusiast
 
Join Date: Jun 2005
Fan#: 24588
Location: Bremerton wa.
What I Drive: 2003 screaming yellow svt

Posts: 114
FF Reputation: 1 99dot Good Standing Member
Buy-Sell-Trade Rating: (0)
I was looking into this a while ago, I was thinking about using the Aux retard on the J&S to a pressure switch to the ground wire on the fuel rail switch or the output from the ECU to the fuel pump ground. Only I couldn’t figure out which wires to splice into.

I think John over at J&S would be able to answer this question. As they know how to bypass most of the information that the ECU sees.

"Issues are fuel PSI dropping to 23psi at 4800 and 22psi , Focus has 72lb Inj and AF is holding but the injectors are maxed out because of the low fuel psi"

I was thinking this is why its so hard to make power with the powerworks kit as you loose 40 to 60hp for the blower and even thou i'm running 60lbs injectors and a Bap I can't make any more power unless I lowered the AFR. Then again I'm still learning.
99dot is offline  
    Reply With Quote
Reply

Bookmarks & Social Networks

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
Need help with this code. 9318 DomestikZx3 General Technical Chat 17 07-11-2012 09:59 AM
upgrading the fuel pump project2point General Forced Induction 4 01-02-2007 08:16 AM
Fuel pump or more? themangina69 ZETEC Performance (2000-2004) 1 06-29-2005 08:07 PM
Is This a SVT Focus Fuel Pump? Bark General Forced Induction 3 05-28-2005 09:48 PM
Fuel Pump SinCityZX3 General Technical Chat 9 05-19-2005 06:37 PM


All times are GMT -5. The time now is 01:55 AM.


Copyright 2002-2014 FocusFanatics.com. All Rights Reserved : Terms of Use : Privacy Policy : Advertise Information : Site Map

Focus Fanatics Ford Focus Forum offers many fun ways for you to engage with other Ford Focus Owners from across the world. Whether it be about the aftermarket performance modifications, technical how-to's, European tuned suspension or awesome fuel economy similar to the Acura TLX or Fiesta ST. You can find all Ford Focus and Focus ST related information here. Join our Ford Focus discussion forums and chat with local Focus enthusiasts in your area.