Fuel Q's for you.

[Flycaz]

Since you will (eventually) be tuning both of my turbo-mustang projects, I wanted your input.

Backround info:
1999 GT currently swapping in an Aviator Motor to run N/A, then, after I pay off my wedding this fall, will be getting a solid block and installing twin 57mm's. HP goals will eventually be 600-700 when complete.

The 00 V6, which is currently my DD while I finish the DOHC convert, will be getting a low boost (7-10 psi) single. No specific HP goals... just to make this dog more fun to drive daily.

For my 00' V6 I'll be putting in a Ford GT pump with 1/2 hard line feeding the stock rails.

For the DOHC TT I was planning on adding the stock line from the V6 and running dual Ford GT pumps with each having its own stock line to the rail (I have a Sullivan intake and rails.)

But now I'm wondering if I should just sump the tank and go return-style... My neighbors son-in-law has a Diablo tuning shop in West Palm and he was telling me that tuning the Returnless at those HP levels will be a nightmare. Since you will be the one tuning it I wanted your input....

Thanks in Advance,
Davey

[Flycaz]

Hmmmm Just saw where this was.. sorry I should have put it in General. Well I guess the product is YOU :)

[Justin@VMP]

If you were to run dual GT pumps and stay returnless you would also need to go with dual FPDMs.

Its possible to work with high HP returnless systems but it can be a challenge, and there are some little things that might never be able to be fixed. With your HP goals and the fuel system modifications that you already have planned I would say go return. Keep the rail pressure sensor installed, and use a relay triggered by the FPDM to power the fuel pumps. I can set that all up in the tune so the FPDM outputs 100% duty cycle all the time and the comptuer adjusts injector pulsewidth if rail pressure drops off for some reason. Do a wiring upgrade on the V6 too.

[Flycaz]

Okay thanks, Those sound like good suggestions.

On that note... since the pumps will be at 100% Duty... would you recomend running some sort of RPM or hobbs switch ( set at 2-5 psi) to control the 2nd pump as to keep fuel temperature down?

[Justin@VMP]

Okay thanks, Those sound like good suggestions.

On that note... since the pumps will be at 100% Duty... would you recomend running some sort of RPM or hobbs switch ( set at 2-5 psi) to control the 2nd pump as to keep fuel temperature down?

you could do that, there may be a spike in FP when it comes on though

[Flycaz]

Okay... Answers only bring more questions.

Do you think the GT40 style pumps (turbine type I belive) will run okay at 100% Duty all the time? i.e. relayed direct battery power...

Since they are cheaper than any other HP pump I was thinking or running them in the return style confuguration.

I was tossing around sumping the tank and running twin externals but I'm now leaning tword;

1.) baffeling my stock GT Tank
2.) modifying the hat for a 5/8 line
3.) using the original feed for a return
4.) Running twin GT40 pumps powered, as you sugggested, via relays triggered off the FDPM.

My car rarely sees 1/2 empty so I'm not worried about pump starvation.

[Justin@VMP]

I think that they might be okay to run full speed all the time. If you are going to run dual pumps then also run dual lines.