Lenin

Which Walbro pump fits the best in place of the OEM? I see that for the 255 LPH version there are multiple models, GSS340, GSS341 and GSS342. Need to add some fuel.

scboost

Lenin,,, You may remember me from the e55 fuel pump issue thread in my c32. well.... e55 pump doesnt EVEN fit so i went with an aeromotive stealth 340lph. it fits great!! i was going to do a diy to show people the install. I just installed it last night and it runs great. Its quiet and it's built to be used with pulse width modulated cars like ours. Walbro's really arnt that reliable imo with other vehicles ive modified.


http://www.sparktecmotorsports.com/a...id=20861070197

Pansu

I and others have Walbros in here, works just fine. First i had 255 and then i chance 400LPH(some modding in fuel lines..) Walbro is cheap, so that why many use them

Lenin

What was the part number for that 400 pump? Was it F90000262?

Pansu

It is normal 400LPH, not E85 model. But if you put that, you may need some modding in fuel lines(and electricity), flow is too high for stock lines and wiring is too thin.
255LPH works just fine with stock lines, plug and play.

Lenin

Thanks. I'll consider it. I hear that it does run a little hot but is not as loud as the Walbro 255.
What are you building if you need this pump? I know things get lonely in Finland in the winter but a 400LPH fuel pump in a C32? Are you going with -8AN fuel lines and an -6AN return?

scboost

Lenin I don't think you would be disappointed with aeromotive. Just the quality of the pump itself is worth the 50 extra dollars. I had a walbro in a sc400 with a 2jzgtte. It worke d as well. It just looks mass manufactured and cheap to me. Probably just the difference in the packing and instructions that gave me the warm fuzzy on the aeromotive

Lenin

Believe me, $50 after 12 years of ownership is the least of my concerns. Just want to pick the right pump and only do it once. And your input is very appreciated.

Pansu

I got it cheap, so why not. Otherwise the gas lines are so tight, that better be the pump where is power. And if car power is near 500hv it is not too overpowered pump with those small sized lines.
And the thought was to try to use E85 on some point..

raf12690

Dumb question here. Our stock fuel pumps are in the gas tank right? Did you retrofit it externally like slk32/srt6 or are these replacements going to remain internal?

Lenin

I'm putting it right where the OEM pump is. inside the tank. No need to change anything. BTW, I decided to go with the Walbro GSS340 for now. Both Walbro 400 and Aeromotive 340 would require upgrading the wiring to 10GA wire and I don't feel like doing it now.

scboost

lenin, is the c32 a return or returnless system? is it pulse width modulated?

Pansu

Fuelfilter has regulator and there is fuel return line back to fueltank.

Lenin

Our injectors use pulse width modulation and are controlled by the ECU. Not sure how, if at all, the fuel pump plays a role in driving or determining the pulse width.
Regarding the return line, as Pansu indicated, there is a return line (hard blue line) going back from the filter to the sending unit that is on the driver side in the fuel tank.
The question for Pansu or anyone else is: what is the best way to connect an AEM fuel pressure regulator and a looped fuel rail? Should I run a separate return line from the regulator to the tank? Should I get a check valve? Bypass OEM filter? Just don't feel like experimenting with the fuel system.

Pansu

I have AEM regulator(after rail) in enginen bay and i have looped rail. Original filter i replaced with "no regulator" filter. And i have new return line, AEM to fueltank. In not sure if that is the best way, but that i have

Sorry my bad english, hope you understand something

Lenin

Thanks. I understand you fine. Did you use a check valve between the filter and the rail? And what did you do with the pressure differential line that used to go from the old filter to the tank? Did you just capped it (closed off)?

Pansu

No check valve and i capped that hose.

Lenin

I'm changing to a filter without the regulator and since I'll be installing an AEM FPR after the fuel rail, I feel that I need to go with the check valve after the fuel filter. Already started purchasing parts. Should be done with the pump install on Monday. The rest will be installed later after I figure out what I want to do with the fuel line and the rail.

Lenin

I need a recommendation on how to secure the new Walbro pump in the old basket. The old pump had a lip on it to which the top of the basket is attached. The new Walbro pump is thinner and shorter. I can get a foam sleeve but am interested in knowing what others had done. Also, any need to replace the feeder pump to match the new Walbro or will it keep up?

crembz

Hey mate, I just ordered new pierburg pumps from rexbo yesterday. Figured I might as well do both... The feeder pump is cheap compared to the main.
https://mbworld.org/forums/showthread.php?t=543433

Lenin

Not sure why you are changing all the pumps but I'm adding more fuel with the larger pump and was asking if the old feeder pump can keep up with the new main pump. Otherwise both of my pumps are fine. In your case (hissing noise from the filter area) I would have started by replacing the filter (unless it is more than just hissing).

Lenin

The installation is complete. The car runs. That's always a good thing after swapping essential components like the fuel pump. Additional good news is that the fuel pressure is up to 65 PSI from 56 PSI. Need to do more testing under WOT but so far the Walbro 255 pump is doing what I thought it would do. Next step is 8AN fuel line and AEM FPR.

raf12690

Glad everything worked out! You thinking about going stacked again now with the extra fuel? Boostmonkey's results on his slk were very impressive.

Lenin

I'm already running stacked. My issue was running a little bit leaner than is safe at WOT at higher RMPs, so I just refrained from running the car hard. I need to update my sig. It still says 181mm pulley. I'm leaving the country for a few weeks. When I come back I will finish my testing and complete the install of larger fuel line and the FPR. The fuel rail has already been completed. Same as boostmonkey's with 8AN in but with only 6AN for the loop.

raf12690

Bump for updates. Hows the car running so far?