Welcome to the North American Subaru Impreza Owners Club Tuesday July 7, 2015
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 > Built Motor Discussion

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 01-10-2007, 02:02 PM   #51
David Buschur
Former Vendor
 
Member#: 24301
Join Date: Sep 2002
Location: Wakeman, Ohio
Vehicle:
2006 WRX 345hp/345tq
White

Default

Hang on, if I understand what you are talking about that is not over running the regulator. If you overrun the regulator the fuel pressure goes up and cannot be brought down. This happens because the return port in the fuel pressure regulator is too small and cannot bypass enough fuel back to the tank.
* Registered users of the site do not see these ads.
David Buschur is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 01-10-2007, 02:50 PM   #52
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 David Buschur View Post
Hang on, if I understand what you are talking about that is not over running the regulator. If you overrun the regulator the fuel pressure goes up and cannot be brought down. This happens because the return port in the fuel pressure regulator is too small and cannot bypass enough fuel back to the tank.
Wouldn't fuel pressure appear to go down as the injectors sprayed more fuel? Once the system would "equalize", then the fuel pressure would behave as expected (fuel pressure went up as manifold pressure went up). It just seemed like the stock FPR couldn't return enough fuel under idle / high vacuum conditions... low vacuum and boost were fine.

It made sense at the time... and now, with the new regulator in place, everything is 100% normal.
x99percent is offline   Reply With Quote
Old 01-13-2007, 03:37 PM   #53
WRX-Blue-Mica
Scooby Newbie
 
Member#: 37938
Join Date: Jun 2003
Location: Indonesia
Vehicle:
02 WRX
Blue Mica

Default

Quote:
Originally Posted by David Buschur View Post
Hang on, if I understand what you are talking about that is not over running the regulator. If you overrun the regulator the fuel pressure goes up and cannot be brought down. This happens because the return port in the fuel pressure regulator is too small and cannot bypass enough fuel back to the tank.
I just sent you a PM, please check it. Thanks!
WRX-Blue-Mica is offline   Reply With Quote
Old 01-15-2007, 09:55 AM   #54
David Buschur
Former Vendor
 
Member#: 24301
Join Date: Sep 2002
Location: Wakeman, Ohio
Vehicle:
2006 WRX 345hp/345tq
White

Default

The fuel pressure should be stable at idle. As the boost goes up the fuel pressure should rise with the boost and when the boost hits its maximum point the fuel pressure should stay right at this corresponding peak. The fuel pressue should not drop then until the boost starts falling off or you lift of the gas. The duty cycle of the injector is a "slow" linear change so it will not cause the fuel pressure to spike or drop.
David Buschur is offline   Reply With Quote
Old 01-15-2007, 12:52 PM   #55
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 David Buschur View Post
The fuel pressure should be stable at idle. As the boost goes up the fuel pressure should rise with the boost and when the boost hits its maximum point the fuel pressure should stay right at this corresponding peak. The fuel pressue should not drop then until the boost starts falling off or you lift of the gas. The duty cycle of the injector is a "slow" linear change so it will not cause the fuel pressure to spike or drop.
...and I agree. That's how it *should* have worked. I guess the lowest fuel pump duty cycle run by the Hydra (~50%) was too much for my stock FPR (at the time, 100% stock fuel system aside from a Walbro and injectors).

Off idle, fuel pressure would actually go down, and then it would behave normally as vacuum decreased / boost increased. Now with the Aeromotive regulator, everything is normal again.
x99percent is offline   Reply With Quote
Old 01-15-2007, 01:34 PM   #56
David Buschur
Former Vendor
 
Member#: 24301
Join Date: Sep 2002
Location: Wakeman, Ohio
Vehicle:
2006 WRX 345hp/345tq
White

Default

That could be the case, I don't have anough experience with the rails/lines/regulator on the Subi to say. I would have a hard time believing though that running the pump at 50% DC that is would overrun the regulator, I know in an EVO it will not. The regulator in the EVO is very small too.
David Buschur is offline   Reply With Quote
Old 01-16-2007, 03:29 PM   #57
SloRice
Scooby Specialist
 
Member#: 44351
Join Date: Sep 2003
Chapter/Region: MWSOC
Location: Cincinnati, OH
Vehicle:
2004 Mitsubishi Evo
701whp 9.91@146

Default

Copied this from David's thread in the "General Community" I thought it was a little more fitting to add it to this thread.

Quote:
Originally Posted by David Buschur View Post
First, I am posting this a little early. As soon as Nick gives me the address and total my vendor status will be paid. Hopefully I can slide this information in. I will delete the pricing from it.

Hi everybody.

This is going to be a long one

Well we have been doing a lot of testing over the last 6 months. This is the longest we have waited to actually get the information out there from any testing we have done. Today I finished up the last of what I needed to do on the fuel systems for the EVO, the fuel lines are the same size for the Subaru (actually slightly larger which is good on the Subaru).

As anyone that actually knows anything about us knows, we pride ourselves on selling you what you need and what works more than just selling crap that isn't needed or won't work as well as something else we know exists. That's how we want treated and that's how we treat our customers.

With that said, we have done quite a bit of testing and such on the EVO fuel system, all of this pertains to the WRX/STi. There is some extra information in here about the fuel rail and fuel pressure regulator on the EVO that WILL NOT PERTAIN TO THE SUBARU.

First let's talk about the fuel pumps. Most every EVO shop that sells a Walbro pump for an EVO sells the GSS342 pump. This pump will also fit in the Subaru. The Subaru pumps I have seen are the 307's, which is a pretty sorry pump. It does not flow very good.

Here are the specs on the GSS 342 pump at boost levels that are important. This is flow testing the pump at 13.2 volts.

60 psi the pump flows 360 lb/hr
70 psi the pump flows 332 lb/hr
80 psi the pump flows 285 lb/hr
100 psi the pump flows 160 lb/hr

So the first place to look is about 40 psi which is close to rail pressure at idle, or your base fuel pressure. This really doesn't matter either as the car isn't going to run at 40 psi for long. As the boost comes up the fuel pressure raises 1 psi for each 1 psi raise in boost pressure.

To make this easier I am going to break it down in another "chart":

At 60 psi this pump is good for 600 flywheel horsepower
At 70 psi this pump is good for 553 flywheel horsepower
At 80 psi this pump is good for 475 flywheel horsepower
At 100 psi this pump is good for 260 flywheel horsepower

As you can see, as the pump falls off up top you can't make as much HP with it. The higher the base fuel pressure is set and the higher the boost goes the less the pump flows. So for a high horsepower, high boost application it just dies up top.

What happens is people end up putting in a big injector thinking they are out of fuel injector and as the pressure is falling the duty cycle is being ramped up higher and higher. We are guilty of this as much as anyone. Not anymore.

I was going to go into what happens with you bump the voltage of the pumps from 13.2 to 15 volts but most of you are not interested in doing that and it is going to make this post so long nobody will read it. You can figure about 17% gain in flow. That will get you close. So it is substantial.

With the base pump out of the way now we can go onto our Modified High Output Walbro pump.

0 psi the pump flows 510 lb/hr
40 psi the pump flows 410 lb/hr
60 psi the pump flows 362 lb/hr
70 psi the pump flows 340 lb/hr
80 psi the pump flows 310 lb/hr
100 psi the pump flows 250 lb/hr

This makes this pump good for:

At 60 psi this pump is good for 603 flywheel horsepower
At 70 psi this pump is good for 566 flywheel horsepower
At 80 psi this pump is good for 516 flywheel horsepower
At 100 psi this pump is good for 416 flywheel horsepower

As you can see, if you are running high boost this pump really flows up top compared to a standard Walbro 255.

My brothers car and my car both ran out of fuel. I was able to run my EVO RS up to 542 whp on our dyno with the single Modified High Output pump we sell. I had 1200 cc injectors in the car running them at 100%+ duty cycles. The car ran a 9.97 at 142.32 mph like that. I was running our adjustable fuel pressure regulator kit on the stock fuel rail. This is where the testing started as my brother and I were both having the same troubles. Datalogging fuel pressure it was simple to find the problem. We were out of fuel pump.

Neither of us wanted to cut up our perfectly good EVO's to put in fuel cells. Neither of us wanted to run AN lines, I do not like AN lines. They dry out and crack and are prone to leaking after about 5 years. They are heavy, there is no real nice way to install them perfectly on a car. They are expensive and mostly, they just aren't needed.

My quest for a great double pumper(twin intank pumps) set up began. After careful study of the tank assembly and knowing I didn't want to hack into the factory wiring and didn't want to loose the factory fuel gauge I came up with an idea. First I needed more research. I called the best in the industry and got some flow rates of what the factory fuel lines could handle. Pushing fuel through a 5/16" fuel line you can supply enough fuel for 1,000 flywheel horsepower. This is exactly what I wanted to hear. No street EVO or Subaru that I am going to want to actually drive is going to make that much power. A four cylinder engine making that much power is laggy as hell, no fun to drive and is more than likely dedicated for track. At that point, throw the stock fuel tank out, put in a lightweight fuel cell. My main concern was ease of installation and I wanted to be able to keep using as many stock components as I could.

I built the first double pumper set up and installed it in my RS. It worked absolutely amazing. The car went so rich that the car would barely run at WOT. After dialing in the AFR's again, back to where they were, the duty cycles dropped from 113% down to 65%!! At this point I had the adjustable regulator still on the car with the base pressure set at 50 psi. I was also still running the stock fuel rail. At this point it was obvious I didn't need a set of 1200 cc injectors in my car. I pulled them out and put in our 1,000 cc injectors. Those are pricing for our EVO injectors.

The duty cycles of course went up a little, no problem. Then I decided to put the stock regulator on and see if I could still get by. No problem. The car was now making 590 whp (up from 542 when it ran 9.97) on 1,000 cc injectors, stock fuel rail, stock fuel lines, stock fuel pressure regulator!! The duty cycles were 84%. That's freaking great!

The double pumper kits are direct drop in units. Non of the factory wiring is tapped into. It plugs in directly. We are using the same wiring bulk head fitting that is used in some Formula One fuel cells. The kit includes a pressure switch that is wired in for the 2nd pump only. At 16 psi of boost the 2nd pump is triggered to come on. For those of you that don't know the EVO doesn't have an external fuel filter. So it cannot be changed unless you buy a new fuel pump assembly. This is stupid. Our double pumper comes with a stainless steel inline 5 micron fuel filter. For the Subaru some have the filter built into the tank, for those the kit comes with this same external filter to install. Slo Rice did a nice write up with pictures on our double pumper. The filters can be bought seperately so you can change filters as needed in the future.

More data:

Our double pumper with two standard GSS342's in it will flow:

At 60 psi the twin pumps are good for 1200 flywheel horsepower
At 70 psi the twin pumps are good for 1106 flywheel horsepower
At 80 psi the twin pumps are good for 950 flywheel horsepower
At 100 psi the twin pumps are good for 533 flywheel horsepower

Our double pumper with two of our Modified High Output pumps in it will flow:

At 60 psi, 1206 FWHP
At 70 psi, 1133 FWHP
At 80 psi, 1033 FWHP
At 100 psi, 833 FWHP

Now, a note. There is some loss running two pumps together into a common line. I am going to eventually send these pumps out, for my own curiosity, and have them flowed through the Y that we use.

Right now what is important is we have a solution for 99% of EVO/Subaru owners to go well into the 9's with minimal changes with a very high level of safety as the majority of the factory components are used.

More information coming.....
SloRice is offline   Reply With Quote
Old 01-16-2007, 03:29 PM   #58
SloRice
Scooby Specialist
 
Member#: 44351
Join Date: Sep 2003
Chapter/Region: MWSOC
Location: Cincinnati, OH
Vehicle:
2004 Mitsubishi Evo
701whp 9.91@146

Default

More info...

Quote:
Originally Posted by David Buschur View Post
I'm not done yet

Few weeks ago we had a friend/customer in here with his bad ass EVO. Car is set up like our black car, just like it actually. I was starting to dial the car in and at around 740 whp I started having problems. The car was going lean. Didn't make sense. This car had a fuel cell, -10 AN lines, Fuel pressure regulator etc. OH BUT WAIT!! The car was running the stock fuel rail! I went and got a fuel rail and installed it. Problem fixed. This car ended up making 790 whp on our dyno. This is basically the same number our black car made when it ran 8.95 at 163 mph. Let me remind you all, that regardless of what the dyno says we do have the quickest EVO8 in the world. This dyno isn't built to give numbers to brag about, it's built for tuning.

This made me think further about what mine and my brothers car was going to need next. What part was going to hold us back next?

Today I brought my EVO to work. Put it on the dyno. Double checked the tune and dialed the AFR's in nice and flat.

Next step was to install a new fuel rail. Replace the stock one.

When I installed the new rail I put a new stock fuel pressure regulator on my car. The regulator was off an EVO9. Exact same part number. My stock regulator was bent slightly on the return outlet, not sure how that happened.

First pull on the dyno the car was LEANER with the new fuel rail. I was puzzled. I checked the vaccum sourse to the regulator, check air temps, coolant temps. All was the same. Made another pull, same leaner AFR's. At this point I am thinking WTF?! I go get my stock EVO8 pressure regulator and bend the outlet back where it is suppose to be, bolt it back onto the new fuel rail and make another pull. This put the AFR exactly where it was with the stock rail. Conclusion is, the stock fuel rail is good enough for up to 740 whp on our dyno, figure about 890 flywheel or Dynojet power.

Something to add to this. I do not like the stock rail. It appears as though the ends are epoxied on, it is poorly designed inside (although I have to say it works and is olive drab green. For what a fuel rail costs, it's not a horrible thing to spend your money on.

My conclusion to this is the stock fuel system, lines, rail, regulator on the car is a very well designed part. The saddle tanks work excellent, especially if you are autocrossing/roadracing. I personally do not want a race car I drive on the street. I want a street car I can race. That is what I have and I am trying to design parts that make a goal like this more affordable and safer for all of us.

If you are using all of these components with the stock regulator and run out of fuel with your particular injector, switching the adjustable regulator can fix the problem. My next step will be putting the adjustable regulator back on when I get close to maxing out these 1,000 cc injectors again.

**The last few paragraphs are obviously EVO only. The Subaru as we all know have their own unique problems with the fuel rail, lines and regulator. I will be working on those problems in the months to come.

Here is a picture of the double pumper, complete setup for the Subaru's.

BRJrod (4:56:03 PM):

Hope you enjoy the tech.
SloRice is offline   Reply With Quote
Old 01-16-2007, 09:03 PM   #59
David Buschur
Former Vendor
 
Member#: 24301
Join Date: Sep 2002
Location: Wakeman, Ohio
Vehicle:
2006 WRX 345hp/345tq
White

Default

Thanks Slorice.

I paid my vendor payment today. Now I can sell something haha
David Buschur is offline   Reply With Quote
Old 01-22-2007, 04:13 AM   #60
WRX-Blue-Mica
Scooby Newbie
 
Member#: 37938
Join Date: Jun 2003
Location: Indonesia
Vehicle:
02 WRX
Blue Mica

Default

Quote:
Originally Posted by David Buschur View Post
Thanks Slorice.

I paid my vendor payment today. Now I can sell something haha
Just sent PM to you, Please check ... thanks
WRX-Blue-Mica is offline   Reply With Quote
Old 02-17-2009, 08:47 PM   #61
06rexwagon
Scooby Specialist
 
Member#: 114730
Join Date: May 2006
Chapter/Region: SWIC
Location: Albuquerque, NM
Vehicle:
2006 WRX Limited Wag
9.8@150

Default

Bumping an old thread. Any more information in the last year? I'm running E85 and maxing out my 950cc injectors. I plan on running some 1200cc injectors soon.
06rexwagon is offline   Reply With Quote
Old 02-17-2009, 09:52 PM   #62
jays05
Scooby Specialist
 
Member#: 78165
Join Date: Dec 2004
Chapter/Region: South East
Location: SC
Vehicle:
05 STI 35r + e85

Default

I have the buschur dual walbro setup in my STI. It works. Not much else to say besides that.
jays05 is offline   Reply With Quote
Old 02-18-2009, 08:23 AM   #63
06rexwagon
Scooby Specialist
 
Member#: 114730
Join Date: May 2006
Chapter/Region: SWIC
Location: Albuquerque, NM
Vehicle:
2006 WRX Limited Wag
9.8@150

Default

Well I guess I need to get one then.
06rexwagon is offline   Reply With Quote
Old 02-18-2009, 08:23 AM   #64
06rexwagon
Scooby Specialist
 
Member#: 114730
Join Date: May 2006
Chapter/Region: SWIC
Location: Albuquerque, NM
Vehicle:
2006 WRX Limited Wag
9.8@150

Default

double post!
06rexwagon is offline   Reply With Quote
Old 02-18-2009, 08:34 AM   #65
jays05
Scooby Specialist
 
Member#: 78165
Join Date: Dec 2004
Chapter/Region: South East
Location: SC
Vehicle:
05 STI 35r + e85

Default

If you are planning to run new braided fuel lines from the tank to the fuel rails, take a look at the Full Blown setup.
jays05 is offline   Reply With Quote
Old 04-20-2009, 11:51 PM   #66
crisdiarata
Scooby Newbie
 
Member#: 208730
Join Date: Apr 2009
Default

Hello guys just want to know if anyone can tell me how to connect dual walbro 255 pump external and in-tank, I want to know both so I will do the easy one, what I hear is than dual external is better.
crisdiarata is offline   Reply With Quote
Old 05-11-2009, 05:52 PM   #67
jonnies
Scooby Newbie
 
Member#: 84430
Join Date: Apr 2005
Location: Brazil
Vehicle:
2006 wrx

Default

Hey David,
can i use your dual walbro to run E100 on my dom3?
so far i have single walbro and dw 1100cc but it wont be enough when i run E100...what u think?is it better than going with a inline bosch 044?will i need other mods?will the dual setup suck air(my biggest concern)?

thanks
jonnies is offline   Reply With Quote
Old 05-16-2009, 01:31 PM   #68
0to115in11
Scooby Newbie
 
Member#: 140832
Join Date: Feb 2007
Default

I have an 06' STI running this setup, using 1200cc injectors and making 460 whp on a dyn odynamics dyno. My car has ran good in the past but seems to have issues going more and more lean over time. Running on E-85 I have been shooting for a base pressure of about 55 psi. Is this correct? Or should it be higher-lower?
0to115in11 is offline   Reply With Quote
Old 08-04-2009, 04:07 AM   #69
Mecka20000
Scooby Specialist
 
Member#: 176162
Join Date: Mar 2008
Chapter/Region: SCIC
Location: South Torrance, CA
Vehicle:
MY02 Jesus Once Told
Me, "Numbers Sell"......

Default

Does any one know where to get the pressure sensor relay he uses in this kit?
Mecka20000 is offline   Reply With Quote
Old 08-04-2009, 04:18 AM   #70
Mecka20000
Scooby Specialist
 
Member#: 176162
Join Date: Mar 2008
Chapter/Region: SCIC
Location: South Torrance, CA
Vehicle:
MY02 Jesus Once Told
Me, "Numbers Sell"......

Default

found it. http://www.mamcoswitches.com/vacuum-...s/lf20-v1.html if you ever need to replace your old one from the kit.
Mecka20000 is offline   Reply With Quote
Old 08-05-2009, 11:16 PM   #71
SloRice
Scooby Specialist
 
Member#: 44351
Join Date: Sep 2003
Chapter/Region: MWSOC
Location: Cincinnati, OH
Vehicle:
2004 Mitsubishi Evo
701whp 9.91@146

Default

Or you can just call Buschur Racing and get a replacement switch.
SloRice is offline   Reply With Quote
Old 11-10-2009, 05:04 PM   #72
andrewhans
Scooby Newbie
 
Member#: 154128
Join Date: Jul 2007
Location: Feltwell, UK
Vehicle:
1987 Volvo 240DL
Red

Default

this is the correct link to the pressure switch

http://www.mamcoswitches.com/pressur...ches/lf20.html
andrewhans is offline   Reply With Quote
Old 02-10-2010, 09:16 AM   #73
hectowrx
Scooby Newbie
 
Member#: 109155
Join Date: Mar 2006
Location: Puerto Rico sin city
Vehicle:
2003 white wrx ej205
11.2@124 feel the panic!

Default

does anyone can tell me where to get the wiring bulk head on this set up , ive been runing dual walbros on my car for over 3 year now no complaints but i havent been suscesfull in fuel vapor goin to the cabin throught the electrical cable routing or at least could Mr. david bushur sell me one???

Last edited by hectowrx; 02-10-2010 at 09:53 AM.
hectowrx is offline   Reply With Quote
Old 02-10-2010, 06:49 PM   #74
hectowrx
Scooby Newbie
 
Member#: 109155
Join Date: Mar 2006
Location: Puerto Rico sin city
Vehicle:
2003 white wrx ej205
11.2@124 feel the panic!

Default

bump bump
hectowrx is offline   Reply With Quote
Old 03-23-2010, 02:22 PM   #75
rexworx
Scooby Guru
 
Member#: 103232
Join Date: Dec 2005
Chapter/Region: Tri-State
Location: GTX3076R-276/272, STX67
Vehicle:
MY05 GDA,MY04FXT6spd
2.5ltr,PPG,Front LSD,4.44

Default

Back from the dead RTV or something like that will seal it. Just make sure to use something that gas, and or e85 wont eat it.

Im looking for a place to find a Y splitter the the two pumps...

Im wondering how this will work, or if a should use something more like a Y?

http://www.beveragefactory.com/draft..._fitting.shtml

Last edited by rexworx; 03-23-2010 at 02:31 PM.
rexworx is online now   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
FS: BRAND NEW Buschur Racing Modded Walbro 255l Fuel pump blowbyu24 Engine/Power/Exhaust 19 03-02-2007 12:53 PM
Buschur Racing High Output Fuel Pump Dasani Engine/Power/Exhaust 1 02-28-2007 10:00 AM
Buschur Racing High Output Fuel Pump Dasani TXIC Private Classifieds 3 02-28-2007 09:56 AM
Anyone have dyno results of Buschur racings modded 255l fuel pump blowbyu24 Built Motor Discussion 6 02-26-2007 12:32 PM
alternative to intank dual walbro fuel pumps tino Factory 2.5L Turbo Powertrain (EJ Series Factory 2.5L Turbo) 4 09-18-2005 09:34 PM


All times are GMT -4. The time now is 09:50 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2015 Axivo Inc.
Copyright ©1999 - 2015, North American Subaru Impreza Owners Club, Inc.