I'm building up a LS/VTEC with 84.5mm cp 11.5 compression using a gsr p&p head on stg 2 cams. I was shopping for a fuel pump and there seems to be a few to select from but i dont know what i might need for this motor. There is a option of 190 and 255 and a 255 hp fuel pump. Which one is recommend?

 

255

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDM94EG28 &raquo;</TD></TR><TR><TD CLASS="quote">255</TD></TR></TABLE>

 

190 LPh should be plenty...255Lph will obviously work as well but is mainly suited for boosted motors. Your engine is only gonna use so much fuel, excess goes back to the tank which is why it physically doesn't matter which one you use. If the 255 Lph is a lot more, I'd stick with the 190 Lph.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 00Red_SiR &raquo;</TD></TR><TR><TD CLASS="quote">190 LPh should be plenty...255Lph will obviously work as well but is mainly suited for boosted motors. Your engine is only gonna use so much fuel, excess goes back to the tank which is why it physically doesn't matter which one you use. If the 255 Lph is a lot more, I'd stick with the 190 Lph.</TD></TR></TABLE>

Oh...i c...well i am planning to put nitrous later on, better get a 255 just in case...or even with nitrous i might not need it?

 

I run nitrous on my car and it's a daily driver with the stock fuel pump and no problems at all. What you have to remember is that on a daily driver, your nitrous would only be "on" maybe 1% of the total operating time. The only nitrous system that places any real demand on your fuel system (other than a high power nitrous system) is a dry system. A 190Lph fuel pump is a decent upgrade over stock and will flow plenty for a nitrous application used on the street and some strip use. Boosted cars are "on" all the time and place a much higher demand on the fuel system consistently. A 255Lph pump wouldn't be mandatory for those setups until the power level gets up there, but it would be considered "better suited" for those applications.

 

Just wondering why basic math indicates that stock fuel pumps are more than sufficient for mild to wild all-motor set-ups yet people continue to insist on upgrading them. I smell a conspiracy...j/k

BTW I put down 203/156(stock EX Pump 79lph, 310cc)
and 214/153 (Stock Dx Pump 79lph, 310cc)

Fact: Liters to Cubic Centimeters: 1 L = 1000cc's

Example 79 lph pump = 79,000 cc's per hour

So, 79,000 cc's per hour divided by 60 minutes = 79,000/60 = 1316.66 cc's min

So, 1316.66 cc's min/4 injectors = 1316.66/4 = 329.16 cc's min

Which is plenty large enough to support a 310cc/min injector.

In turn that would indicate that an upgrade to the 135lph would be all that is needed in most cases for a healthy buffer of fuel volume.

Example: 135lph x 1000 = 135,000 cc's/hour

135,000/60(minutes in the hour) = 2250cc's/min

2250/4 injectors = 562.5 cc's/min (Would support 560cc 's per injector)

Basically for all intents and purposes I will only refer to the majority of modified Hondas/Acuras.

Fuel Pump Ratings are as follows:

1988-2000 Civic CX, DX, EX = 79 lph
1989-2001 Integra RS, GS, LS = 79 lph
1999-2000 Civic SI = 135 lph
1994-2001 Integra GSR = 135 lph
1997-2001 ITR = 135 lph

Modified by EG-B20vtec at 10:44 AM 12/14/2006


Modified by EG-B20vtec at 4:04 PM 12/18/2006

 

hum...so you guys are saying that my stock GSR fuel pump is good enough for my all motor set up...

Stage 2
P&P gsr head
s2 IM paired with a holley 68mm tb
84.5mm or 85mm CP 11.5

 

dude just upgrade the fuel pump to 255 and ur good to go

 

Why do it if it's not needed?

 

Sorry for the questions, but what are the specs of a stock B16a or B18C fuel pump?
Is it a must to upgrade?

 

Read this http://www.hondata.com/techfuelpump.html

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by koczeka &raquo;</TD></TR><TR><TD CLASS="quote">Sorry for the questions, but what are the specs of a stock B16a or B18C fuel pump?
Is it a must to upgrade?</TD></TR></TABLE>

Read MAN!!!

It's right there for the whole world to see.

As I said above...

Fuel Pump Ratings are as follows:

1988-2000 Civic CX, DX, EX = 79 lph
1989-2001 Integra RS, GS, LS = 79 lph
1999-2000 Civic SI = 135 lph
1994-2001 Integra GSR = 135 lph
1997-2001 ITR = 135 lph

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RStoR &raquo;</TD></TR><TR><TD CLASS="quote">Read this http://www.hondata.com/techfuelpump.html</TD></TR></TABLE>

So basically HONDATA believes as I do that if you use the stock fuel pumps at 32- 40 psi and only upgrade your injectors you will ample fuel to support your engine's requirements.

Great link...As it further underlines the fact that my math was correct.

&lt;&lt; Gives self a pat on the back.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bLack* &raquo;</TD></TR><TR><TD CLASS="quote">dude just upgrade the fuel pump to 255 and ur good to go </TD></TR></TABLE>

dude you really dont need a damn 255lph fuel pump, thata OVERKILL

 

I have read that article years ago.
With my question I just wanted to highlight that stock fuel pump might be adaquate for most of us.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SkankyEJ7 &raquo;</TD></TR><TR><TD CLASS="quote"> dude you really dont need a damn 255lph fuel pump, thata OVERKILL</TD></TR></TABLE>

im running a 255 on a 2L motor, its fine

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bLack* &raquo;</TD></TR><TR><TD CLASS="quote">

im running a 255 on a 2L motor, its fine</TD></TR></TABLE>

All that means is that your engine's only using a certain amount of fuel that could easily be supported by a 135 lph stock fuel pump. At least 120 lph and more is just being sent right back to your gas tank through the return line.... That's money spent to just send more fuel back to the tank in reality...unless you're boosting and using an FMU, it's hardly worth it.

 

hum...i guess stock gsr fuel pump is good for 240whp+ from what i'm hearing..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JFG Kevin &raquo;</TD></TR><TR><TD CLASS="quote">hum...i guess stock gsr fuel pump is good for 240whp+ from what i'm hearing..</TD></TR></TABLE>

From what I was saying at the top...there shouldn't be a question. Think for yourself a little. Read it this time...understand it...Stop Worrying!

Start with a 135 lph pump.

Convert lph to cc's...(Because we use cc's for Hondas)

135 x 1000 = 135,000 cc's per hour

Convert to minutes...

135,000 lph divided by 60 minutes = 2250 cc per min

2250cc divided by 4 injectors = 563 cc per min

SO THIS MEANS THAT A STOCK GSR PUMP WILL SUPPORT UP 550cc INJECTORS WITH NO FUEL DELIVERY ISSUES!

 

Good explaination....but sometimes numbers dont relate to how well something works...Especially electrical or mechanical, I'm just making sure that people have done it before and can tell me what they know about it. I'm rebuilding a motor and probably going to be my last motor build with Honda's i just want to do things right from the beginning.

 

a 255 walboro pump is only 104 dollars so why not get one if anything you may end up need it in a later build. Just like everyone else has said it wouldnt hurt anything so why not.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by smileycvc &raquo;</TD></TR><TR><TD CLASS="quote">a 255 walboro pump is only 104 dollars so why not get one if anything you may end up need it in a later build. Just like everyone else has said it wouldnt hurt anything so why not. </TD></TR></TABLE>

Because as this thread clearly points out....it makes no sense to spend even one dollar let alone $104, just to send more fuel back to your gas tank....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 00Red_SiR &raquo;</TD></TR><TR><TD CLASS="quote">

Because as this thread clearly points out....it makes no sense to spend even one dollar let alone $104, just to send more fuel back to your gas tank.... </TD></TR></TABLE>

I couldn't put it any better...