Walbro 255

[bodge]

While we are on the topic of fuel pumps, who is running a GTR pump. I have been told that if you wire a GTR pump to get consant 14.5 volts. it can support up to 400RWKW is this correct? I had a walbro in my car and now l have a GTR pump wired

up in the mentioned configeration supporting well over 300RWKW.

[blitzxtr]

My R33 25 made 362kw with walbro in tank which is about 497 horsepower roughly but there was no fuel in return line LOL!

[The Mafia]

While we are on the topic of fuel pumps, who is running a GTR pump. I have been told that if you wire a GTR pump to get consant 14.5 volts. it can support up to 400RWKW is this correct? I had a walbro in my car and now l have a GTR pump wired

up in the mentioned configeration supporting well over 300RWKW.

400rwkw out of a GTR fuel pump? Sounds like a load of shit to me.

I got 300rwkw out of my walboro 255lph, BUT it wouldn't go below 12.8:1 afrs... I didn't mind because I run WMI.

I opened the injectors full on the power fc and the afr's didn't change.

So it would be safe to say that the walboro 255lph could only hold 250rwkw safely. Anything else and you're asking for a blown engine.

Anymore more than 14psi of boost is asking for trouble with them too. A lot of people are too ignorant to understand that boost has a heavy impact on the fuel pump that you are running cause boost is pushing back on the injectors..

[boosted_32]

could a bosch 040 intank handle 350rkwk? cheers

[Evil34]

I could be wrong but i think you would need an external set up to safely push 350 rwkw, especially if you are going to hit the track with it.

So you would need a surge tank, bosch 044 and use the pump already in the tank as a feeder.

Just my opinion though

[boosted_32]

I could be wrong but i think you would need an external set up to safely push 350 rwkw, especially if you are going to hit the track with it.

So you would need a surge tank, bosch 044 and use the pump already in the tank as a feeder.

Just my opinion though

Im not guna be hitting the track but I was hoping I didnt need to go external, I have spoken to a few people and everyone has had different opinoins so far which makes it even harder

[Rav]

Can some one just anser the Question i would like to know as well Because i have a bosch 044 in tank.

[govich]

Have you seen the flow chart? Watch the blue line below 60psi.... Terrible!

Are we conveniently ignoring the purple line? I think all that graph tells you is that you need to make sure you get the HP version (GSS342) of the pump for an application up to 500hp, as rated.

[DECIM8]

Well Ill answer your question,

NO A WALBRO WILL NOT HANDLE 350+ RWKW..

NO A WALBRO WILL NOT HANDLE OVER 14PSI (I.E will no longer work at max capacity)

NO A WALBRO WILL NO SUIT YOU, YOUR OTHER OPTIONS ARE NISMO, TOMEI (they are the best options) YOUR OTHER OPTION IS A BOSCHE 040.

Nismo and Tomei drop in, Bosche 040 requires modifications.

(I got all this infomation from reading this thread, perhaps you should also do this.)

Edited February 14, 2008 by DECIM8

[boosted_32]

Well Ill answer your question,

NO A WALBRO WILL NOT HANDLE 350+ RWKW..

NO A WALBRO WILL NOT HANDLE OVER 14PSI

NO A WALBRO WILL NO SUIT YOU, YOUR OTHER OPTIONS ARE NISMO, TOMEI (they are the best options) YOUR OTHER OPTION IS A BOSCHE 040.

Nismo and Tomei drop in, Bosche 040 requires modifications.

(I got all this infomation from reading this thread, perhaps you should also do this.)

Well I cant see how a bosch 040 will handle that sort of power when the pump only flows 102l/h @ 6.5bar, maybe at least a bosch 044!

[The Mafia]

can people just understand that the xxxl\ph means nothing unless you look at the pressure against it?

For example -

205l/h at 70psi will flow more than a pump that does 255l/h at 40psi WHEN the pressure required is say, 60psi.

[rob82]

We run the 500hp walbro's in the xr6turbo's and repeatedly and reliably see 350rwkw. Thats on a 4bar system with 14psi manifold pressure. So a total of 72psi of rail pressure. These pumps work fine in clean tanks!

[The Mafia]

thats fair enough, just as long as they aren't the low pressure ones that companies have sold to people telling them they are a "500hp" pump

My Nismo is a 275lph @ 70psi. Plenty of fuel, trust me.

[govich]

NO A WALBRO WILL NOT HANDLE OVER 14PSI

So it won't be able to handle a 2530 pushing 18psi on an RB25? Sure?

I agree it won't handle 350rwkw, it's not rated to.

[boosted_32]

lol well where on topic wot do u recon 168l/h @ 5bar could handle?

[DECIM8]

Im just preaching what people are saying..

14psi + 38psi fuel presure = 52psi .. was it not said that that pump was tested at 3bar? 14.2psi x3 = 42.6psi .. so 14psi is already higher than rated presure..

So your no longer running 255lph.. its still working but your running less fuel because of more presure.

Thats my understanding of it all, btw I cant remember what one bar is in PSI so its round about that.. I no its 14.2 or 14.7 isnt it?

[GeeTR]

14.503'ish

[paulr33]

risk vs cost i guess is important here

if you can save $300 but you find the AFR's drop off the face of the plannet at 5000rpm on full load, lean out city + rebuild time

then is it really worth the cost saving? why go all out on a psycho build only to skimp on something as important as fuel delivery

no fuel is fine, less fuel than expected is not however, thats when it leans out off the planet and rebuild light comes on

[The Mafia]

14psi + 38psi fuel presure = 52psi .. was it not said that that pump was tested at 3bar? 14.2psi x3 = 42.6psi .. so 14psi is already higher than rated presure..

This is right in the money. Well done.

[govich]

Im just preaching what people are saying..

14psi + 38psi fuel presure = 52psi .. was it not said that that pump was tested at 3bar? 14.2psi x3 = 42.6psi .. so 14psi is already higher than rated presure..

So your no longer running 255lph.. its still working but your running less fuel because of more presure.

Thats my understanding of it all, btw I cant remember what one bar is in PSI so its round about that.. I no its 14.2 or 14.7 isnt it?

Who says you NEED 255lph at 14 psi? You have a nice graph that Mafia posted on the previous page showing you the flow characteristics for the pump. You can work out that at 52psi pressure it's supplying approximately 204lph. The next step in claiming that the walbro outright can't handle 14 psi would be to work out how much fuel the RB25 needs.

From http://www.skylinesaustralia.com/forums/FY...-Fl-t47081.html (you'd want to confirm this), the RB25 injectors flow 440cc/min at 52psi. 440cc/min = 26.4lph, for 6 cylinders that's 158.4lph. Less than 204lph if my maths is correct.

So please stop preaching rubbish.

Edited February 14, 2008 by govich