Opinions appreciated... Any drawbacks or negatives about doing his mod?

 

Drawbacks could include:

__Loss of water-separating media in primary filter-- the filters I've run as primaries have single, pleated media. Many spin-on pre-pump filters have a water drain though.

__Loss of fuel heater and WIF sensor

__No drain valve on primary filter

__Not stock, aftermarket components

I've had mine deleted for about 15 months and have been happy with the new setup.

 

For me I would hate to lose the air return feature.
With the OEM system, the FPR valve is the highest point of the system so it provides a natural place to purge air from the system during fuel filter changes etc.

I also like having the Parker sleeve fittings to minimize leaks caused by vibrations.

As far as I know, there isn't anything wrong with the OEM arrangement so I don't see the benefit if deleting. I know of several trucks that dyno around 500 rwhp while still using the stock fuel bowl set up.

 

I think most do it as part of a regulated return setup. I'd like to know of other advantages and what the HP limit is on the stock setup as I've considered going with a Strictly Diesel bowl delete kit.

 

I don't know what the HP limit of the stock system is but it's pretty high. Are you thinking of a 500 hp plus build?

 

I've always wondered what that term means....
The stock fuel system is a type of regulated return, although it's not easily adjustable. Do the aftermarket systems have an external adjustment screw so the return pressure can be set to a specific psi?

 

The after market setups flow fuel thru the heads then to the regulator so any air that gets to the heads has an escape path. They also use an adjustable regulator.

 

Oh OK...thanks for the explanation. So, the 'return' is post injectors? That sounds pretty cool.

Were folks having problems with air getting into the cylinder head fuel rails? Seems like any air that found it's way to the fuel bowl would exist via the FPR first...

 

Tiny air bubbles can make their way into the fuel rails. A regulated return also offers more stable fuel pressure to the injectors so a long lead injector is no longer needed in the number 8 position. There is another cheaper solution that keeps the stock fuel bowl called FRX from Riffraff.

 

That is interesting. How unstable is the fuel pressure to the injectors when using the stock system?

 

Because of the firing order and fuel system design, Ford uses the LL injector in no 8 to prevent starvation and quiet it down.

 

The stock system has regulator at fuel bowl and is around 50-55psi I think. Problem is when you increase demand of the fuel system with more hp or bigger injectors, the pressure drop across the rail is significant, but fuel bowl pressure is still consistent.
A regulated return holds pressure across the injectors steady because it regulates pressure after the injector instead of before.

Next issue is air. Yes during filter change its nice to bleed air from bowl quickly but the ford design is known for inducing mini bubbles causing some of the noise produced by the injector. This is caused by the pump sucking fuel from the tank with quick disconnect fittings designed for pressure and not suction. A regulated return or even a metered return like riffraff sells (frx) will help the injectors by creating a path for the fuel to go after the injectors instead of dead ending the fuel rail and forcing the air through the injector.

Last, getting rid of fuel bowl...
My opinion, this is unnessisary for a street truck. It will support 400+ hp just fine.
Like was said, it has water in fuel sensor and a heater (if you live in cold climate) and the most significant thing, awesome filtration. The filter is like a 5micron filter or something crazy. And I think you can get a 2 micron replacement filter. Baldwin and fleetguard make filter heads and filters to replace what you remove, but it's generic and requires some fab work to hook it up and stuff.

Unless you are building a race truck or a toy with big oil and big sticks, you don't need to remove the stock fuel bowl.

 

That is interesting, I would not have guessed that.

Robin's truck has hybrids with his fuel pressure sensor post injectors (in the CCK adapter). I believe his fuel pressure was pretty constant around 65-68 psi and would drop about 8-10 psi at WOT. Stock fuel bowl. I believe his truck dyno'd around 480-490 hp and held the low ET slip from RRE for a couple of years.

Maybe Robin did something special so his fuel rails held more pressure? Unfortunately he isn't with us any longer to ask questions and learn from...

 

It is a shame, we lost a lot of experience we can't get back.
But the cackle cure kit (cck or frx) was to get the air bubbles out of the rail, and that's exactly what I'm talking about. The fuel bowl pressure was fine, but line loss and consumption made it run down to only 10psi. If the regulator was after the injectors, then it would maintain set pressure up to the limit of the pump and fuel lines.