Fuel Pressure Issue at High Boost - XFI Data Log Screenshot

[Hatdragracer]

Orange data is Fuel Pressure, Green data is Boost

At the peak of the boost is 21.1 lbs
Fuel pressure dropped to 43.6 lbs
TPS was at 59%
Injector duty cycle was 96% (yikes)
AF Ratio was 11.6
Alky was on
No ESC Retard
Stock Fuel Rails and fuel lines

I have a Walbro 340 pump with a hotwire kit so I never thought I would have to worry about fuel supply with mild setup.

I will start with a new fuel filter to see if that is the issue, I also have an Accufab regulator that I have not installed yet....I dont think it is a regulator problem as the FP follows boost well until higher boost levels. On this run the FP followed the boost 1:1 until about 12 psi of boost then trailed off, the FP caught back up when I let off the throttle.

Do the Accufab regualtors have lower resctriction than a conventional Adj. FP Regulator?

 

[turbobitt]

A few things may be going on.
First, although the fuel pump may be capable of supplying the proper amount of fuel per there rating, you must check there charts to see how much flow is reduced as pressure increases. So for 20 psi boost your pump now has to work harder at ~63.5 psi for example.
Second, how is your fuel rail plumbed ? With stock fuel lines and rail I'll assume its single feed. I had fuel pressure control issues with a single feed and using the same pump and regulator and dual feeding the rails I was able to fix any fuel pressure tracking problems.

In any case, you look like your just running out of pump.
AG.

 

[87GN_70GS]

A 340 pump at 66 psi (assuming your base FP is 45 psi) will provide about 55 gph of fuel. Six 60 lb injectors at 96% DC require about 60 gph. You do not have enough fuel supply.

 

[V6sleeper]

Could his stock lines be too small for the 340?

 

[Mr.Spool]

Need to check the volts to the pump and add a volt booster if you don't have one already,volts really wake up the pumps

 

[Hatdragracer]

I will change the filter, and look into the voltage booster. The volts on the hotwire kit was 13.4 - 13.5 with the engine idling and lights on.
Is this is what you were suggesting as a booster?
http://www.casperselectronics.com/store2/product_info.php?products_id=614

 

[bison]

Why risk melting an engine with a single pump? If this was a stock ECU with a non Wideband chip you would likely have melted it already and be spending thousands fixing the damage from lean out. Imo you should be putting 2 new pumps or at least 2 tested pumps in there before proceeding and verifying voltages. Either that or reduce the mass flow. Chances are your pump is shot.


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[Boost231]

Or one large single pump

 

[Mr.Spool]

or one working pump with proper voltage

 

[Hatdragracer]

Any twin pump options out there besides Racetronix?

 

[Lil Truck]

Any twin pump options out there besides Racetronix?

Before you buy, I would drop the tank and inspect the Pump, pick up, and the short hose from the pump for possible leakage at high pressure.

I had a hose blow out on a new pump within 1 year of the install.

 

[Boost231]

Any twin pump options out there besides Racetronix?

Www.arizonagn.com