fuel pump

[tony/ka24de]

does anyone know the size of a ka24de fuel pump? And what would be a good upgrade for 8psi setup?

[Nathan]

Just get the Walbro 255lph man, they are super easy to install and will do what you need.

[SingleCamSam]

Why upgrade your fuel pump for 8psi? Especially on a 97(likely low miles). Guys have run 750cc injectors at stock pressure with the stock fuel pump.

[WDRacing]

Its just over a hundred bucks, why not upgrade it?? Running 750cc injectors with a stock pump isn't the smartest thing I've ever heard. 750 injectors will come close to starving the fuel rail and pump.

WD

[tony/ka24de]

what size fuel pump is the factory one? The only reason I don't want to run a 255ph is because my I have put one in my friends sr and it runs rich even at idle.

[Nathan]

Then his fuel pressure regulator isn't working correctly.

[andrave]

its an OLD fuel pump cause its your stock one. why not go with cheap insurance????

[Projex240]

Wd's right...the fuel pump wont stand up to it. &50 flow more than the pump can. But the rail can support more fuel flow than any 240 can make. The fuel rail is a 6an(per stillen) This is the same size as the 300zx fuel rail. They have been proven to flow over 600 to the wheels on these stock fuel rails. The pump however wont stand up. you can get the walbro 255 for your car for 85 dollars on ebay right now. If you cann find a 155 lph pump for cheaper, do it. Thos support up to 425 hp. Summit sells them.

[s13conv]

In the DSM world the walbro 255lph pump has been know to increase the base fuel pressure by as much as 17psi. -which would explain the sr running rich at idle. He probably needs to reduce the base fp back to stock with his regulator. Depending on the lph the stock pump flows, maybe the walbro 190lph hp would be good. I have read on here that replacing the fuel pump on NA KA's has made a noticeable improvement. It would only help more for a boosted application.

[huguetpj]

In the DSM world the walbro 255lph pump has been know to increase the base fuel pressure by as much as 17psi. -which would explain the sr running rich at idle.

If the base fuel pressure is going up I would say the fuel press reg is bad...

[andrave]

not necessarily, I've read stories of high volume/high pressure fuel pumps like the walbro outflowing the stock regulator. I've never known someone to replace the stock one with a new stock one though, they usually assume its inadequacy so they upgrade.

[s13conv]

I believe some of it has to do with the ID of the fuel return port being too small.

[huguetpj]

Could be... I'll just have to find out myself once I install the Walbro 255lph HP pump I have lying aroung my room...

I'll let you guys know

[daniel240]

by the way, how the hell do you install the walbro 255 on the s14. i just spent an hour looking for the damn pump. i put the rear seat down and pulled the carpet back and took that plate off and there was a round thing with 3 hoses going in and 2 elec. conectors. i took that off and still couldnt find the pump.

[andrave]

um, on the S13 the pump pulls out with "that round thing."And I have been running a 255 walbro in my NA ka24E with no problems since may. no changes except a TTZ fuel filter.

[daniel240]

well i did have a full tank of gas so couldnt really see much, so is the pump like down inside the gas tank. that "round thing" was conected to a couple wires and a hose that went down into the tank, so are they attached to the pump?

[andrave]

well when you pull the cover off it is attached to the fuel pump.

[Nathan]

That round cover should have a metal chassis reaching down into the tank. The pump is kinda at the bottom of it and yes, there is hose that connects to the top of it. Just pull that thing ALL the way out. You might want to clean really well around it too if you dont want a lot of dust and dirt falling into your gas tank.

[daniel240]

ok so the pump just kind of hangs down there and is not secured to anything?

[andrave]

its in a cage that is attatched to the cover. So its secured by the screws that you undo to lift the assembly out. Its a big one piece assembly with the level sender/float, the pump, and the cage all together. the pump sort of "snaps" in place with big rubber donut on the bottom.

[daniel240]

so would it be easier to do with an empty tank?

[andrave]

wouldn't make a difference. The assembly lifts out.

[tony/ka24de]

what size is the factory fuel pump