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Discussion Starter #1
I have the FiTech Command Center I and would like to understand more about how to moderate the fuel pump so that I'm not fully dead heading this thing at full power, which as you all probably know, causes a lot of heat build up. The information on these data points is lacking so if anyone can reply with details, that would be great. What can I safely adjust in these settings?



My Current Settings:
/Go-EFI PRO Tuning/Fuel Pump Control/
Pump Prime Time [ 5.0 ]

Flow for PUMP ON [ 75.0 ]

MAP for PUMP ON [ 95.0 ]

TPS for PUMP ON [ 25.5 ]

RPM for PUMP ON [ 3000 ]

Volts for PUMP ON [ 9.0 ]

PWM Low Flow [ 40.8 ]

PWM Mid Flow [ 89.8 ]

PWM High Flow [ 97.6 ]



My data logs do show that when I'm out on the highway cruising below 3,000rpm, I do have a lower Fuel Pump reading and when above 3,000rpm, my Fuel Pump reading is at 100. Appears to be working. One change I'm considering is that since my typical long trip rpm range is 3,500rpm cruising, I should probably push up my RPM setting to 4000. I did notice that if below that RPM setting and I smash the pedal to above 25 (TPS for PUMP ON), it does go to 100 so I know that is working. The lowest fuel pump reading I'm seeing in my log is 55 and the highest is 100.
 

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My #'s are the same as yours, except RPM pump on is 2500.
Have you considered modifying your FCC and make the vent into a 'return'? I never had issues with my FCC, but it does get hot. Even though I was running it at 40%. I took the float out at the beginning of the summer and the FCC stays nice and cool converted to a 'surge tank'. The only issue i've noticed is if the car is on a hill, the fuel in the line can drain back to the tank. I need to grab a checkvalve..
 

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Discussion Starter #3
Mdelgado, with that pass through, does the "from gas tank" pressure gauge on the FCC show any fuel pressure?

My FCC does run hot with my current setup. Very hot to the touch. The pass through mod looks easy but I want to give the FiTech recommended way of "lower pump config" a second look. I read and watched all the videos on how this FCC supports up to 1200HP but wow, I'll never need that kind of pump availability so I certainly need to consider reducing the power.

Aside from very hot, I'm second guessing my from fuel tank pressure gauge reading. When I first start the car, I have 5lbs from my inline mini pump but at some point that pressure gauge goes to zero, or is bouncing on zero. I've been driving like this for weeks now, since first noticing, so I appear to have fuel. I even replaced the inline pump with a Holley pump and I'm getting the same zero reading. Wondering if this is normal. Never noticed it before... but wasn't looking either.
 

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66 El Camino 57 Chevy pickup 2004 Tahoe
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if it's really zero the engine will die instantly. You may need a better quality gauge.
 

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66 El Camino 57 Chevy pickup 2004 Tahoe
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where exactly is the gauge tapped into the system.

After all the problems reported with FCC switch it to a return type system as suggested by Mike Degado. Many have been fixed this way. Of, if you've still got enough hair to pull out you can try to fix the FCC.

There's a huge thread in this section (over 1000 posts) detailing problems and fixes for the FiTech.
 
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Mdelgado, with that pass through, does the "from gas tank" pressure gauge on the FCC show any fuel pressure?

My FCC does run hot with my current setup. Very hot to the touch. The pass through mod looks easy but I want to give the FiTech recommended way of "lower pump config" a second look. I read and watched all the videos on how this FCC supports up to 1200HP but wow, I'll never need that kind of pump availability so I certainly need to consider reducing the power.

Aside from very hot, I'm second guessing my from fuel tank pressure gauge reading. When I first start the car, I have 5lbs from my inline mini pump but at some point that pressure gauge goes to zero, or is bouncing on zero. I've been driving like this for weeks now, since first noticing, so I appear to have fuel. I even replaced the inline pump with a Holley pump and I'm getting the same zero reading. Wondering if this is normal. Never noticed it before... but wasn't looking either.

My low pressure gauge broke within the first couple weeks. Apparently they don't like the inconsistent pressure of mechanical fuel pump, so the needle bounces til it breaks. After 4 attempts of getting Fitech to replace it under warranty, i gave up. If you truly had no pressure, the FCC would drain and you'd lose high pressure and engine would die.
also, i saw no difference in FCC temp when reducing it's capacity down to the suggested 40%
 

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Discussion Starter #7
After watching several "how to" videos on youtube for converting this FCC into a surge tank by removing the float and vent filter, I did it and it only took around 10 minutes to do the actual modification. My FCC now passes fuel from the low pressure side to the vent, which is a return back to my chevelle gas tank. The FCC is now only warm to the touch, it is no longer hot. I found a $10 sink strainer nut wrench from Home Depot (picture attached) which made quick work of unscrewing this thing.

I now have an expensive surge tank style design which is common for road course cars. I keep telling myself that this is a good thing.

Aside from the FCC being a dud, I'm still very impressed with the consistency I have with this Fitech setup.
 

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Discussion Starter #8
There's a huge thread in this section (over 1000 posts) detailing problems and fixes for the FiTech.

Thanks Tom. Well aware of that huge thread. So huge that it is only usable if you were to use the search feature to find discussion related to what you are looking for. I once tried reading the whole thing and only got to around page 100.
 

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Since I've converted my unit to a surge tank I have noticed I lose fuel pressure fast. I don't know if its directly related, but it makes for issues when starting. I've never shared a vid on Imgur, and the sound didn't work for me, but you can watch the fuel pressure. I cycle the key on, and quickly goes to 60psi, then a quick decrease in pressure as the injectors cycle and back to 60. Then you can see how it quickly loses pressure down to 40 until I start cranking the motor and the pump turns back on.



I was able to fix this issue by picking up a Russel Performance Inline check valve. I put it before the fuel filter so the line is pressurized.

Just something to keep in the back of your mind if, as a result, you have fuel pressure issues as well.

 

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A buddy of mine and I put the base model 400 hp fitech on a '72 c-10 with a bone stock 350. We used the single pump G surge tank (part number 40007) and mounted it sideways out of necessity. We used the stock fuel system, including a mechanical pump, to feed the tank. The tank fed the EFI unit, and the return from the EFI unit went back into the surge tank. Thus, the high pressure pump was recirculating fuel through the EFI unit back to itself. The only way fuel could escape this loop was to be injected. It (the tank) ran VERY hot to the touch on hot days here in AL. It started randomly dying on the owner, and we determined the problem was vapor lock in the surge tank. Noting that the truck had a return line from the original mechanical pump (the pump on the truck presently is a holley, which lacks a hookup for that return line) we teed off the return line from the EFI unit to the surge tank and connected to the unused return line. This resulted in MASSIVELY cooler surge tank temperatures and no more stalling.
 
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V8440, I was wondering why you didn't opt for the retro-fit in tank pump kit for the truck set up since it is only a bone stock 350 engine set up

And a question in general, are only the FITech kits with the FCC having issues? I'm looking at getting the 600hp kit with the retro in tank setup.
 

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V8440, I was wondering why you didn't opt for the retro-fit in tank pump kit for the truck set up since it is only a bone stock 350 engine set up

And a question in general, are only the FITech kits with the FCC having issues? I'm looking at getting the 600hp kit with the retro in tank setup.
Nope FiTech initially shipped the retro tank with in-tank pump using cheap hose on the pump. The hose they used to connect the pump to the I/O bulkhead wasn't designed to be in fuel full time. Several reports of found off road dead from the hose bursting in the tank and no fuel pressure. Anywho, if you get FiTech's retro tank and pump setup, check the hose on the pump. Myself I would just replace it with the right stuff regardless. It's about $10 a foot, but you only need a foot.

If you are talking about the Holley retro sender with pump, I have no idea if it works.
 

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I seem to recall that we didn't retrofit the tank because the retrofit setup would not work with really tall tanks, which this is. Being a '72, the fuel tank is behind the seat and is much taller than a passenger car tank is. From a technical standpoint, I would much prefer to mount the pump in or just under the tank, but budgetary constraints limited us in this case. Had it been my truck, the pump would have either been in the tank somehow or right under it, well away from engine heat.
 

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Discussion Starter #14
Update: I took a 4 hour trip over the weekend and was a little surprised at how warm my gas tank got. Now that I re-engineered the FCC several months ago, this was my first long trip where the engine ran at 3500 RPM for hours which put my FCC pump at 100% power. During my rest stops, I checked and sure enough the FCC unit was hot but no where near as hot as it used to be so this was a "win" for my FCC. However, I noticed an unusual side effect and that was my gas tank got to around 120 degrees (F) -- temp is a good guess. Wondering if anyone else experiences the same and if this should be considered normal for the gas in your main tank to get noticeably hot. In my case, compounded by the fact that my gas tank vent was clogged which is how I discovered an issue as the pressure in my tank built up to the point that gas was seeping out one of the lines. Now that I'm home, I blew out the vent with a direct shot from my air compressor line and sure enough it was clogged.
 

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Do you have a vented cap as well.

Your scenario makes sense. All that heat from the FCC had to go somewhere. It was just transferred slower since the fuel volume is larger in the tank.

I wonder why FI marine Outboards with VST tanks (essentially a FCC) don't have this heat buildup...
 

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A possible solution could be a restriction in the return line to the tank. The Robbmc powersurge has a restriction in the return line....just a thought ?
 

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Discussion Starter #18
One question I have that I need to do some trial-and-error on, do I need 100% fuel pump power all the time? Or in my case, small block chevy with maybe 450hp, do I really need 100% fuel pump, ever?

If I can run this pump at a lower power level, the heat buildup will be less.
 

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My Current Settings:
/Go-EFI PRO Tuning/Fuel Pump Control/


PWM Low Flow [ 40.8 ]

PWM Mid Flow [ 89.8 ]

PWM High Flow [ 97.6 ]



My data logs do show that when I'm out on the highway cruising below 3,000rpm, I do have a lower Fuel Pump reading and when above 3,000rpm, my Fuel Pump reading is at 100. Appears to be working. One change I'm considering is that since my typical long trip rpm range is 3,500rpm cruising, I should probably push up my RPM setting to 4000. I did notice that if below that RPM setting and I smash the pedal to above 25 (TPS for PUMP ON), it does go to 100 so I know that is working. The lowest fuel pump reading I'm seeing in my log is 55 and the highest is 100.
One question I have that I need to do some trial-and-error on, do I need 100% fuel pump power all the time? Or in my case, small block chevy with maybe 450hp, do I really need 100% fuel pump, ever?

If I can run this pump at a lower power level, the heat buildup will be less.
What is the current PWM reading at "normal" cruise speeds/rpm?

I'd want 100% at WOT, but no need for that at cruise rpm, even with a return.

Back when I was the guinea pig, and had all of my Fitech FCC issues, I had to go back and forth with them about the pump overheating, boiling fuel out of my FCC "vent" fitting. When they finally admitted there was a Fitech problem, and not an install, or vehicle, problem, I "think" the number they came up with for idle PWM was 45% to prevent pump overheating.

Regardless, I'd probably scale the PWM up from IDLE to WOT and try that.
For example, say IDLE SPEED is 1,000 RPM, and 45% PWM, and..
RPM LIMIT is 5,000 RPM and 100% PWM...
I'd try to average 10% MORE PWM at every 1,000 RPM...

OR....

If it can be simply set at a steady state (regardless of RPM and/or TPS) at say, 65% PWM unless MAP is 90 kPa or higher, then it would only go FULL ON 100% @ WOT...

In a nutshell...89.8 PWM at "mid flow" seems to be much higher than you realistically need
 

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I don't think much if the heat is from the pump itself. Where is your FCC located? If its not next to or in front of the radiator its likely that its picking up hot air from the radiator. I thought I had mine in a good spot out of the airflow but apparently not, I move it next to the radiator and temps dropped dramatically as did my hot start problems.
 
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