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Walbro 450 Lph E85 Fuel Pump Issue/ Power Supply

camoo

By camoo,
in Engines & Forced Induction

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camoo Collaborator

camoo

Posted
Posted

Gday all.

Yesterday I installed the walbro 450 LPH fuel pump into my R34 GTT.

I HAVE NOT REWIRED DIRECTLY FROM BATTERY... yet.

This is the only thing i have changed in preparation for e85, and now under load is missing and breaking down.

The car was running fine with my Bosch making around 300 RWKW.

Have any people had experience with this pump?

Does it require 13-14v to function normally at that KW due to the design of the pump?

Im going to test the LPH output now and see what i come up with, but any advice or experience would be helpful.

Standard lines, rail and reg too.

Cheers, Cam

Ben C34 Grand Master

Ben C34

Posted
Posted

I melted the plug with mine. Definitely needs sometging better than stock for wiring.

http://www.skylinesaustralia.com/forums/topic/423664-melted-connector-plug-due-to-larger-in-tank-pump-pics/

camoo Collaborator

camoo

Posted
  • Author
Posted

Thanks man, I know to get their rated capacity it will require a direct feed, but would the lack of power supply reduce its out put to the point where the car misses?

I thought it would be able to keep up at this stage?

Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted

Thanks man, I know to get their rated capacity it will require a direct feed, but would the lack of power supply reduce its out put to the point where the car misses?

I thought it would be able to keep up at this stage?

That doesn't sound right at all, it will still flow even a lower voltage..

Jab a multimeter on your fuel pump power and see if it rises as you flex the throttle.. even a stationary jab will raise the voltage.

I have a feeling the factory wiring isn't keeping up with the current load and in turn the pump isn't getting what it needs.

camoo Collaborator

camoo

Posted
  • Author
Posted (edited)

That doesn't sound right at all, it will still flow even a lower voltage..

at idle and dabbing the throttle its around 4.3v

Jab a multimeter on your fuel pump power and see if it rises as you flex the throttle.. even a stationary jab will raise the voltage.

I have a feeling the factory wiring isn't keeping up with the current load and in turn the pump isn't getting what it needs.

Edited by camoo
hypergear Grand Master

hypergear

Posted
Posted

I have the same fuel pump. It needs an extra earth to work properly.

Connect it to the factory + / - wiring inside the fuel tank

Out side thank, Tee an earth wire into the factory earth wiring that is connected to the fuel pump. It will then work fine.

camoo Collaborator

camoo

Posted
  • Author
Posted

Ok update is now rewired with 8g wiring. Still doing it. Old pump back in.

Still doing it.

as johnnilicte suggested, im leaning towards plugs may have crapped out due to fueling. But that's a tomorrow job to check.

Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted

I'm going to be re-wiring my pump (same one) with a drop resistor & beefed up relays.. I'll write up a guide once I'm done!

Will retain the factory drop resistor, but on throttle the pump will get full power without melting shit LOL

Ben C34 Grand Master

Ben C34

Posted
Posted

I'm going to be re-wiring my pump (same one) with a drop resistor & beefed up relays.. I'll write up a guide once I'm done!

Will retain the factory drop resistor, but on throttle the pump will get full power without melting shit LOL

If we don't hear back I will assume that you have exploded yourself :)

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