Ok few questions, would doing a suction tube relief enough restriction in the fuel system to run an inline pre-pump fuel filter (I was thinking the BF1212, the Dahl sounds great but too spendy for me) without needing to mess with the mixing valve? Or does it still create enough of an issue? Personally, I don't want to mess with it since if it ain't broke don't fix it but I would like to resolve the potential air in fuel line issues with the suction tube (or draw straw in the dodge world).

I also like the idea of having the back up with the capped factory fuel pick tube still in tact in the VERY unlikely event something would happen...

My father's 2000 f350 is still running the mixing valve in his 240k mile f350 without apparent issue relating to it but what works for him... might not work for me...

 

I guess I'm not sure what you mean by "doing a suction tube". Do you mean to run a larger diameter fuel line between the tank and the pump?

What exactly are you thinking about changing from the stock setup?

The largest sources of entrained air in your fuel suction line are the quick connect fittings at the top of the tank and at the suction of your pump. Getting rid of those connections and using straight tubing connections with clamps will resolve most of your issue.

 

I was planning on using a 1/2" draw straw or suction tube like this:



To 3/8th Parker/Napa fuel line to a baldwin FS1212 on an FB1311 filter head and then to the pump. Effectively it would eliminate the quick disconnects and the little valve on the foot of the stock pick up. I would then plug the stock line so water, dirt and such would not get in. I would be doing pre-pump mods without disassembling the white mixing valve.

My question is does that sound like a good plan or am I shooting myself in the foot by not deleting the mixing valve?

Of course while I have the tank out I will do the harpoon mods.

 

id run a sump and be done with it.

 

From the best I understand, the mixing chamber creates two scenarios....

1) Any entrained air from the quick connects will get re-entered (to a degree) with the fuel being sent to the pump suction, only to end up with even more entrained air than experienced in the first pass through the system. Eliminating the chamber would help only if you still have entrained air coming through the system.

2) Heated fuel (from the return line) will get mixed with the cooler incoming fuel, which could be a benefit during cold weather on startups. Otherwise, this heated fuel ends up slightly reducing your fuel density, but this should only be an issue if you're reaching the fuel flow limits due to full load with extreme HP mods elsewhere throughout your engine/powertrain. Eliminating the chamber will allow for a very slightly higher fuel density coming through your pickup "straw".

That said, unless you're going to be pushing huge HP mods, you're not shooting yourself in the foot by leaving the mixing chamber in place, but only as long as you completely eliminate all entrained air.

However, while you're in there, I would personally go ahead and eliminate the mixing chamber by directing the fuel away from the pickup.

 

Ok guys, sounds like it would just be easier to dump the mixing valve while I am in there than possible have to do it again... thanks!