FITech EFI ?

[bteutsch]

Adding a return line to the tank from the tb has fixed the problems that I was having with the command center. The pump creates a lot of heat and it will get hot all on its own. I tested this by setting the command center outside of the engine compartment and with it running it didn't take long for the command center to start to heat up. After adding the return line it feels cool even after running for long periods of time. Since adding the return line I have not experienced any problems at all.

I just added a return line also, have you had any issue with the mechanical pump keeping up with the electric pump? I haven't run mine except one time down to the gas station and back. Had no problem, however I called FITECH and talked to Bryce today, he told me that the return line sounded like a bad idea. He insisted that my mechanical pump couldn't keep up with the 340lph command center pump and it would run hot when the fuel gets low in the command center. He thinks the best solution is pulse width modulation and slowing the speed of the pump down so it's not dead heading at full speed. I still think the return line is a good solution. Now I'm worried he may be right. My return line is 5/16 fuel line that is adapted down to 1/4 at the tank. Any thoughts?


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[75Bronc]

Are you guys running the Go Street 400HP or the Go EFI 600HP? I am ready to pull the trigger but can't decide which kit to do. Is the only difference timing control? Are any of you utilizing timing control? What distributor do you need with a 302?

 

[blubberfet]

I just added a return line also, have you had any issue with the mechanical pump keeping up with the electric pump? I haven't run mine except one time down to the gas station and back. Had no problem, however I called FITECH and talked to Bryce today, he told me that the return line sounded like a bad idea. He insisted that my mechanical pump couldn't keep up with the 340lph command center pump and it would run hot when the fuel gets low in the command center. He thinks the best solution is pulse width modulation and slowing the speed of the pump down so it's not dead heading at full speed. I still think the return line is a good solution. Now I'm worried he may be right. My return line is 5/16 fuel line that is adapted down to 1/4 at the tank. Any thoughts?


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I am sorry that I forgot to mention that I don't have a mechanical pump because I had vapor lock problems. The low pressure electric pump I have (Holley blue @ 416lph) will outflow the the high pressure pump and I would not have done the return line if the lp pump couldn't keep up.

The pwm does help alot but it still gets warm. My Bronco has always had problems with getting hot on the trail, never overheated but definitely gets hot. By adding the return line I know that the fuel will be as cool as I can get it. I was upset going from the carb to efi and still having problems due to boiling fuel.

I have the 600hp and it is controlling the timing. The distributor is a summit racing billet distributor with a msd adjustable rotor.

 

[blubberfet]

I am also wondering how much fuel actually is returned to the tank. I can hear it entering the tank but the fact that it is running through 2 bypass regulators makes me wonder what the flow of the return is. Most of the fuel should be returned inside the cc with only a small amount being returned to the tank from the second regulator in the tb. Unless the regulator is set at a lower pressure on the tb. At least that's how I see it working.

One day I might pull the return line and see how fast it will fill a 5 gallon gas can.

 

[DirtDonk]

With the return line at the TB unit, it might not return all unused fuel, but it's going to be a lot more than if the return was tapped in between the mechanical pump and the CC. So maybe it's enough.
Even with the CC still recycling some of it's hot fuel, I bet that because it's pushing as much fuel as it thinks the TB needs (fuel burned, PLUS fuel returned to the tank and it can't tell the difference at the CC) I would think that at least half, but perhaps a majority of the unused fuel is going back to the tank.

The CC sees the load as everything that was going to the TB prior to the return line, PLUS anything going through the return line.
Not going to be all of it of course, but I would think at least double the amount of cool "new" fuel is coming in to the CC after the bypass was added.

Just a guess of course. I wouldn't know the math, even if I knew the data to crunch.

Paul

 

[.94 OR]

I have the FCC on mine plus dual tanks.

I intend to run the fuel out of the main tank most of the time then switch to the aux tank. I was playing around with my setup in the driveway, rear tank full, drawing off the aux tank. The vent line for the FCC drains back into the main tank, which caused the main tank to overflow through the filler cap at idle. It was pushing a considerable amount of fuel out just on the vent line. I can't imagine how much would come off a TB return line.

 

[blubberfet]

I have the FCC on mine plus dual tanks.

I intend to run the fuel out of the main tank most of the time then switch to the aux tank. I was playing around with my setup in the driveway, rear tank full, drawing off the aux tank. The vent line for the FCC drains back into the main tank, which caused the main tank to overflow through the filler cap at idle. It was pushing a considerable amount of fuel out just on the vent line. I can't imagine how much would come off a TB return line.

There shouldn't be any fuel in the vent line, at least that's what Fitech says. The only time I have had fuel in the vent line is when the fuel boils in the CC.

Have you adjusted the PWM settings?

On mine Idling or slow driving and the CC would get hot and boil, forcing fuel out the vent. I tried to make the vent a return line by not using a lp regulator before the CC but even at 14 psi I couldn't get it to work.

 

[.94 OR]

There shouldn't be any fuel in the vent line, at least that's what Fitech says. The only time I have had fuel in the vent line is when the fuel boils in the CC.

That was my assumption too so imagine my surprise when it started cascading down my fender flare.

I had set the parameters to the spec's but I still fought this thing all fall, since it took 3 months to arrive. I finally ran out of time, weather and patience. I'll get back to it in a couple months.

My FCC would sound like it was boiling the fuel. Not sure why, but had similar issues when the carb was on it. I'm still thinking of trying a baffle between the FCC and the radiator as it is close enough to adsorb some heat.

 

[Madgyver]

im getting vaporlock issues with a qjet on the firebronco..
efi is just an option