01 with P1SC looking for more fuel pump help

01vert

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Looking for some help getting more fuel without going crazy on my 01 cobra with a P1SC. Currently running a Deatschwerks 340lph pump in the stock basket. Got to 5700 at 451hp and the tuner stopped the pull as the pressure at the injectors started dropping. Looking at the data log it is maxed out on duty cycle and the pressure went from a constant 40 psi and dropped to 37psi at about 5700. Pull was stopped at that point. I was thinking of going to the Deatschwerks 415lph pump and just having him tune the car for the extra rpm but pull timing so the max HP stays the same just at the higher rpm. Make sense to anyone?

Car runs great, I just feel like having the same hp and getting a wider power bandmakes more sense than revving a 4v to 5700 and no more. I know the tuner set the rev limiter at 6500 and understand I could pull in 1st 2nd and 3rd safely to 6500 but not to in 4th. (hope I got that right).


Looking for input on anyone with a single fuel pump setup larger than the 340lph in a return less system. Suggestions on doing a wiring upgrade or any other suggestions to run a single returnless pump to get me to around 6500 rpm?
 

01yellercobra

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That 340 should be enough for your set up. When was the fuel filter changed last? IMO a wire upgrade should be done anytime bigger pumps are installed. Thats where I'd start.
 

01vert

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Pump and filter changed together. Data log shows pump driver maxed out and injector pressure dropping at that point.
 

Badaz01

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I have a boost a pump and a set of 60 lb. injectors I’ll give you a hell of a deal on the bap is brand new vmp and injectors are siemen dekka with about 300 miles on them.
 

thelonebean

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Very odd issue. That pump should be good enough for your power levels. As the person above said the wire upgrade might be worth it but maybe you have a lazy pump. You can always add a boost a pump but if its a lazy pump that's the issue, a boost a pump might just be a bandaid.
 

Blkkbgt

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Did you drill a hole in the basket?

People used to run into the exact same problem with the old focus pump in the GT basket at around 375, Myself included. The 01 cobra setup is the same.

If you look at the basket you'll notice that the pump is mostly fed through a rubber captured check valve on the bottom. Because of this the pump sucks the basket dry and it then starves.

What I ended up doing is drilling a 1/2 inch hole in the front of the basket 1-2 inches up from the bottom. I chose the front because during acceleration it would force fuel into the basket.

You can upgrade the pump all you want but you'll never overcome the flow limitation of the check valve.

And no the basket is not always fully submerged, especially below 1/2 tank. Even at 3/4 full there isn't enough fuel above the basket to flow in through the top to supply the pump.
 

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