I just got the car back togethor. I plan on getting it on the dyno in the next week or so but I dont want to go and find out I need more fuel. The setup: 357 ci, stock heads, cc224/236, vortech t-trim. Right now its getting around 10 psi w/ a 6.66 and a 2.75. I have a 7" that I will be putting on b4 the dyno runs. Fuel setup is pretty simple, stock intank, t-rex, 42 lb inj, and vortech's fmu. I know I will need more fuel, what do you guys suggest?
Scott

 

I am pretty sure you will need more fuel. Both larger injectors (almost certainly) and more pump as well. There are a lot of choices.

In terms of injectors, as you are probably aware, the stock PCM cannot drive low impedance injectors, so you are limited to the high impedance type. The largest high-z injectors that are readily available are in the 50lb/h range. These may be adequate, depending on a number of variables. The main variable is, of course, fuel pressure. The problem is that to pump a given volume, the higher the pressure, the harder it is on a pump. IOW, maximum pump output falls as pressure rises.

WRT to pumps, there are a number of ways to go. Just as a point of reference, I used a 255lph intank with a "Boost-a-Pump" to support 733rwhp on my prior setup. The BaP increases voltage to the pump when under boost. That setup was maxed out and I had to go with a much more elaborate setup this year. What I have now is probably overkill. The twin in-tank setup from Racetronix gets good reviews. I have friend using it and it works well.

Rich Krause

 

Rich thanks for the reply. Do you think that 50's w/ an intank pump will be ok?...I only want to do this once.
Scott

 

Only thing diffrent from my setup than yours is i use a aftermarket intank pump.

I'm using 42 svo's @ 50psi.
I have no problem with fuel and my fmu is basicly out of the loop.

For what it's worth, but Rich knows his stuff...

 

50's are usually adequate with a setup like yours. Needed more injector, so I was running a Superfueler, but you should try the fifties before doing anything radical. It often requires some creative programming to get the pulse widths up where they need to be. Don't be afraid to lie to the computer about the injector size, for example.

Rich Krause

 

Thanks alot for the help guys. What pump would you recommend? Radik which one are you running? What kind of power did your car make radik? Thanks Rich
Scott

 

I was running a Bosch pump. Now I have two Aeromotive pumps!

Rich Krause

 

Why two Rich?

Jack
Racetronix

 

ttt...any specific pump I should check into?

 

Jack: I felt that one very large pump would circulate the fuel too rapidly and heat it up unecessarily. Is this a correct concept? Anyway, I also considered a single large pump with the Aeromotive controller, to operate at two speeds essentially. But I ended up deciding on the twin solution. The second is activated by a boost switch. Works fine, steady fuel pressure and plenty of flow. But is pretty complex and was pricey.

I probably should have just bought your twin in-tank setup!

Rich Krause

 

Yes, those large pumps do put a considerable amount of heat into the fuel...

Looks like you spent a small fortune. I usually recommend dual Walbro GSL392's which can support 1000HP w/o a problem. Two of these pumps can be had for usually less than what it costs for one large Aeromotive. Best part is they are very quiet, they will outlast the Aeromotive units many times over, they don't have the gravity feed issues like the Aeromotive and they draw less power etc...

Jack
Racetronix

 

I'm not sure what your application is intended for but from the sounds of it I would suspect that street use is your primary use.

The Bosh,Walbro and so on style pumps are tough as nails and really do the job and seem to last when it comes to countinous duty. Your combination would benefit well with a bigger Walbro that produces stronger volume/psi. Depending on the motors need for fuel obviously other parts may have to be upgraded. There are many trick systems out there that some of these guy's have in use and work great but my advice would be for ya to first figure out what kind of power you expect to make and then use this formula to figure fuel pump requirements:

Use a hand held calculator and plan on .5 lbs/hp-hr (gasoline). Methanol Alcohol requires about 1.0 lbs/hp-hr. Use .7 lbs/hp-hr when planning a gasoline system for nitrous assist.

EXAMPLE: You have a 650 hp engine. 650hp x .5 = 325 lbs/hr (gasoline). Although you need to know how much your fuel weighs, assume for this example that it weighs 6.2 lbs/gal. 325 lbs/hr 6.2 = 52.42 gal/hr. Dividing by 60 (minutes per hour) yields .847 gal/ min (GPM).

I just purchased a big inch forced induction combination that I will be switching over to in the near future and the recommendation for fuel pumps to look into where either Weldon pumps or Magnaflow. Seeing that I'm currentlly finishing my car up and plumbing the car for current motor I'm not looking to redo this again so I have set the fuel system up to be able to handle the task of the fuel requirements for the forced induction setup that will be going in soon. But the pump I ended up for the motor is a MagnaFlow EFI Pro Star 600. This pump will feed just about anything requiring fuel. The pump will support power 2000+ and rail psi can be from 20 psi to as much as 120psi.

Another factor that can help ya decide what pump to go with will be what your looking to spend?

Cost wise a fuel system can get very exspensive when building but never scrimp on your fuel setup you would be surprised on how much power there may be still left just need to get it to the motor!

Good Luck