255 intank enough for 550whp?

KBCobra95

New Member

Aug 28, 2005

356

0

0

North Carolina

Aug 27, 2006

#1

• Aug 27, 2006

• #1

My car right now has 42#injectors and a walbro high pressure intank fuel pump. At 484whp and 12#'s of boost the injectors are maxed outat 5k RPMS. I was told that upgrading to 60's would be my best bet, but would my pump be enough for the 60's? How about a T-rex inline or something of the sort? Could raising my FP help out the injectors? Right now I still have stock lines FPR and rails. Suggestions please, but I am working on a tight budget. (No money for complete fuel system as of now.)

 

zenboy99

Founding Member

May 12, 2002

2,212

0

47

Madison, WI

Aug 27, 2006

#2

• Aug 27, 2006

• #2

Here's a good calculator section that may help you.

http://www.hardcore50.com/members/calculators.htm

 

Pokageek

Active Member

Jun 10, 2005

2,767

0

46

MA, USA

Aug 27, 2006

#3

• Aug 27, 2006

• #3

255 LPH or liters per hour = 67 gallons per hour. I would say yes but that depends on how you calculate FWHP. BTW, according to that calc, my car will be fine using the 155LPH fuel pump already on it for my 100shot nitrous..Right on the money at 40 gallons per hour = 500FWHP. So makes me wonder how many people are overkilling it with 190's and 255's...CONSIDRING an 255 is good for 825+ FWHP

 

B

bimmertech

New Member

May 3, 2005

1,123

0

0

merriam, ks

Aug 27, 2006

#4

• Aug 27, 2006

• #4

the way i understand it is that the reason you go higher with the fuel pump is when pressure starts building up in the rail then the pump very rarely puts out claimed output.

more pump=insurance. overkill is really not an issue for return style systems--cept for evaporative emmissions.

imo you are starting the push the limits of the stock lines/rails. i can't believe you don't have a t-rex already.

 

OrangeMustangGt

Founding Member

Mar 7, 2002

1,976

0

36

Cape Cod, MA

Aug 27, 2006

#5

• Aug 27, 2006

• #5

In short, NO

I have a walbro 255 high pressure Intank.
When i was on the dyno at only 5psi, i was going lean at the upper rpms

This was with 42lb injectors, 40psi and as the tuner tried to open the pulsewith of the injectors it wasent responding.....

I installed an additional holly inline pump and now my car is rich at the upper rpms because of the available fuel.

As you know, a boosted car needs a Richer a/f ratio to fight detonation so you have to have the extra fuel that a single 255 cant provide.

 

Pokageek

Active Member

Jun 10, 2005

2,767

0

46

MA, USA

Aug 27, 2006

#6

• Aug 27, 2006

• #6

Cool caculator but I guess it needs some other "factors" then. Like are you Forced induction? are you return style system? etc... Guess I am going to install my 255lph pump now. I wouldn't play with your set up either way man. Like when I go to nitro, I am going to get ANOTHER tune to be sure there is no question.

"more pump=insurance. overkill is really not an issue for return style systems--cept for evaporative emmissions."

WAIT! What does that mean? It will put out more emissions and might not pass? Thanks.

 

final5-0

Mustang Master

Apr 6, 2003

6,817

12

79

DFW Texas

Aug 27, 2006

#7

• Aug 27, 2006

• #7

There really is no sense in not having another pump.

Its not like the cost is really bad and when it comes to fuel ...

To have more and not need it is a good thing IMHO.

To need more and not have enough ... well ... that ain't good!

When talking about forced combos, that statememt is all the more true as with those bad boys, they use fuel to help cool down the charge some which takes a bit more.

Besides all that ... at your level ... its not like you don't understand you need big fuel to make big hp.

In the past, I lurked around several power adder forums for a good bit when I was considering going forced.

Most of those boys ran a big in-tank pump AND a second pump like a t rex or similar setup like Ben talked about.

Grady

 

KBCobra95

New Member

Aug 28, 2005

356

0

0

North Carolina

Aug 27, 2006

#8

• Aug 27, 2006

• #8

I thought the lines/ rails were good for like 700? I hear so many different numbers.

bimmertech said:

the way i understand it is that the reason you go higher with the fuel pump is when pressure starts building up in the rail then the pump very rarely puts out claimed output.

more pump=insurance. overkill is really not an issue for return style systems--cept for evaporative emmissions.

imo you are starting the push the limits of the stock lines/rails. i can't believe you don't have a t-rex already.

Click to expand...

 

B

bimmertech

New Member

May 3, 2005

1,123

0

0

merriam, ks

Aug 27, 2006

#9

• Aug 27, 2006

• #9

KBCobra95 said:

I thought the lines/ rails were good for like 700? I hear so many different numbers.

Click to expand...

the lines are the biggest restriction--more exactly the outlet lines for the pump.

i've heard rails are good for 600 or so.

my take is you better pay for insurance, or you will be paying far larger bills for engines.

 

final5-0

Mustang Master

Apr 6, 2003

6,817

12

79

DFW Texas

Aug 27, 2006

#10

• Aug 27, 2006

• #10

KBCobra95 said:

I thought the lines/ rails were good for like 700? I hear so many different numbers.

Click to expand...

IIRC, the fox boys would use our rails and say they would then be good to 600rwhp.

That was about three years ago so take that for what its worth.

Most likely ... things have changed since then as back in those days ... 42's were thought to be plenty for any forced combo

Grady

 

KBCobra95

New Member

Aug 28, 2005

356

0

0

North Carolina

Aug 28, 2006

#11

• Aug 28, 2006

• #11

So 60's and an inline should be sufficient? Complete Aeromotive system coming as soon as I save a little more money (just got married)