Can you use the inline walbro as a flow through?

 

I would deffinitally get a hobbs switch as David has suggested. On your setup, I would kick it on around 16psi.

 

good ?

 

We run 1200cc injectors, Walbro 255hp in-tank and Walbro 255 in-line on our EVO IX with no problems. They're both on all the time. 788whp

 

im wiring mine on all the time as well. dual 255hps in tank and 1000cc injectors with factory feed as return, hoping for 750awhp???

 

if your goal is 750hp you will need bigger injectors.

 

1200cc or 1600cc? RC or PTE? Am I going to need an injector driver box? like an FJO?

Thanks

 

You can get by with 1200cc with dual pumps. We dont run a driver box. No problems

 

what brand?

 

RC Engineering. The 1200cc are expensive though

 

Does anyone have a wiring diagram of how they wired up the second pump to a relay? I need one if someone can help out! Thanks.

PJ

 

I can give you guys a real world scenario as I have added a twin pump housing with two pumps running all of the time. I am running a -8 supply and a -6 return and with both pumps running the lowest I can get the pressure is 44 psi at idle. The biggest restriction is the return going into the pump housing, unless that is enlarged, the pressure will build up there no matter what size return you use. The issue there is that the stock tank uses the return to build a suction to draw fuel from the passenger side of the tank. So the best bet if you do not have any means of adjusting the entire fuel map for the additional pressure is to put the pump on a hobbs switch.

 

If you are using the AEM you can control what psi/rpm/tps/speed you want the 2nd pump to be activated just as I have but using a relay along with LS12 input that is open on the AEM. A diagram is below. This is how I do it and it works flawless, you can monitor the situation also if ever needed.

 

We use a pressure switch on our double pumpers, very simple, very reliable. Having 44 psi of pressure at idle shouldn't cause a problem at all.

 

David, at what psi does the pressure switch that you use turn on the second pump. I recently installed this and was just curious to when it turns it on.