Walbro pumps vs FASS set up

[daytripper63]

Does the Walbro pump eliminate air in the fuel like the FASS does?

 

[Bodie]

The pumps dont elemninate the air in the fuel, it is the filters that do that.

Walbro might I am not sure but they will probly charge an extra $200 for it



Here is all I could find...

GDP filter page

 

[cerberusiam]

The pumps dont elemninate the air in the fuel, it is the filters that do that.

Walbro might I am not sure but they will probly charge an extra $200 for it



Here is all I could find...

GDP filter page

Filters only filter what goes thru them be it air or fluid. The FASS and AirDog pumps are designed to elimiate air in addition to pump fuel.





No, the Walbro does not eliminate entrained air. In fact, the Walbro setup has the potential to significantly increase entrained air due to returning a large amount of the pump ouput to the tank.

 

[drury]

The Walbro doesn't claim to eliminate entrained air, but in practice, it doesn't seem to affect performance much if at all. Keep in mind that any entrained air will enter the common rail, where it will be compressed from about 14. 7 psi to pressures of 10,000 psi or greater. The volume of the entrained air will shrink by a factor of 680 or more at those pressures, whereas the fuel is not compressible. So if it starts out 15% air, it will end up as . 02% air before it is injected in the cylinder and mixed with more air. You will find plenty of very high HP applications running Walbros, and plenty running FASS's, so you probably can't go wrong either way. On the other hand, the Walbro is dead quiet, fluid cooled, high flow, and very reliable. A Walbro won't require any special mods to run with a modded CP3.

 

[robmints]

No, the Walbro does not eliminate entrained air. In fact, the Walbro setup has the potential to significantly increase entrained air due to returning a large amount of the pump ouput to the tank.

Cerberusiam or others that know,

I looked at the instructions for the fass and it has a return line that looks to be the same size as the walbro and they have a manifold type thing that lets the returned fuel go back in the tank just like the walbro. What am I missing? Does the fass have a variable flow or something? Is there a place to see how the fass removes air and is different than the walbro?

 

[cerberusiam]

Cerberusiam or others that know,

I looked at the instructions for the fass and it has a return line that looks to be the same size as the walbro and they have a manifold type thing that lets the returned fuel go back in the tank just like the walbro. What am I missing? Does the fass have a variable flow or something? Is there a place to see how the fass removes air and is different than the walbro?

In the block that the filters mount to and the return line comes from are a set of staggered ports that seperate the fuel by density. The air entrained fuel being some what lighter will seperate and the denser fuel is drawn off the bottom thru another port. That block is really the heart of the FASS and does most of the work that it is intended for. There used to be diagrams and descriptions posted on the web but the links I had are all broken now.

So if it starts out 15% air, it will end up as . 02% air before it is injected in the cylinder and mixed with more air.

I just love the incongruity of this statement. Makes me wonder if the purveyors have EVER shaken a botte of soda pop and opened it. Of course the air compresses, and then it expands right back when the pressure is released. It is simply amazing how basic physics is ignored and then taken as fact.



Hey, maybe I can have 1000 HP and get 35 mpg towing my 5'er! All I have to do is IGNORE the basic rules of nature! :-laf :-laf

 

[MCummings]

If you can eliminate the air, you won't have to compress it.



I would assume that the 15% of air turning into . 02%, that's a difference of 14. 98%. Does that mean the pump has to work 14. 98% harder, or will pump 14. 98% less fuel if we didn't remove the air?



Merrick

 

[drury]

If you're running at the edge with an unmodified CP3, and you actually had 15% entrained air in your fuel, then a FASS would have an advantage. But when you look at the trucks that are making big horsepower, some have Walbros and some have FASS's. In practice, the FASS's don't seem to have any advantage over the Walbros. They do have one big disadvantage in that you have to upgrade them to get them to flow enough with the modded CP3's out there. There's a thread on here somewhere that talks about needing to run the FASS at 40 psi with a modded CP3. The Walbro's can supply a modded CP3 right out of the box, and do it running at a safe pressure (they come set for 22psi).

 

[AMassaro]

The pumps dont elemninate the air in the fuel, it is the filters that do that.

Walbro might I am not sure but they will probly charge an extra $200 for it



Here is all I could find...

GDP filter page

Wow... you've got a chip on your shoulder... where do you get the idea Rich would charge you for something that isn't necessary in the first place. Some of us consider the FASS a good setup. Some of us consider a Walbro much better.

 

[Bodie]

Wow... you've got a chip on your shoulder... where do you get the idea Rich would charge you for something that isn't necessary in the first place. Some of us consider the FASS a good setup. Some of us consider a Walbro much better.

Huh? I am not saying you need it or not, the question was do they offer it. I am saying they charge you $200 for a filter w/ head($25) and some fittings($5). I sell these exact parts to people, I know how much they cost. The point is they charge for something FASS comes with.



I thought this was TDR not DTR, we act like adults over here... .

 

[cerberusiam]

If you're running at the edge with an unmodified CP3, and you actually had 15% entrained air in your fuel, then a FASS would have an advantage. But when you look at the trucks that are making big horsepower, some have Walbros and some have FASS's. In practice, the FASS's don't seem to have any advantage over the Walbros. They do have one big disadvantage in that you have to upgrade them to get them to flow enough with the modded CP3's out there.

If one is chasing HP to the limit there is very little that matters other than consistently stuffing enough air and fuel in the cylinder to get that big number. Entrained air is the least of the inefficiencies encountered at those levels.



A far bigger concern for most of us is a compact easily installed and maintained system that will supply enough clean fuel for stock to moderate HP increases. If it has the potential to provide a little economy and efficacy in the fueling systems its just a bonus.



While the GDP kit is obviously quite competent and reasonably priced it is not as simple to install and plumb nor does it address what this thread is centered around, chiefly the entrained air and its effects.

 

[robmints]

I am saying they charge you $200 for a filter w/ head($25) and some fittings($5). I sell these exact parts to people, I know how much they cost. The point is they charge for something FASS comes with.

I just bought one of the MK+Big Line Kits. I looked at the Aeroquip prices on some of the fittings, found the part# for the head on here, priced the filter and hose. By the time I was done it looked like it would be about $85-$90 depending on where I bought the stuff, I was missing a washer or two and still did not have a bracket. Not to mention the time it would take to get the stuff together. So I bought the kit for $179. I forget what shipping was. I felt it was a good idea to try and filter the fuel to what I believe is what Bosch is recommending. I may end up with a FASS system but $689 wasn't what I wanted to spend right now because my in tank pump is fine for now. But it is not like I spent $180 for somethng I could have gotten for $30, I spent $180 for something I could have gotten for $90 plus a lot of my time. If you want to sell me all the stuff in the GDP Kit for $30 maybe we can make a deal. Hey, I'm not greedy, if he wants I'll sell them to Richard for $40 and everybody will be happy. My point is these guys offer to sell us their stuff and their ideas, we try and educate ourselves and buy what is best for us.

 

[Bodie]

I just bought one of the MK+Big Line Kits. I looked at the Aeroquip prices on some of the fittings, found the part# for the head on here, priced the filter and hose. By the time I was done it looked like it would be about $85-$90 depending on where I bought the stuff, I was missing a washer or two and still did not have a bracket. Not to mention the time it would take to get the stuff together. So I bought the kit for $179. I forget what shipping was. I felt it was a good idea to try and filter the fuel to what I believe is what Bosch is recommending. I may end up with a FASS system but $689 wasn't what I wanted to spend right now because my in tank pump is fine for now. But it is not like I spent $180 for somethng I could have gotten for $30, I spent $180 for something I could have gotten for $90 plus a lot of my time. If you want to sell me all the stuff in the GDP Kit for $30 maybe we can make a deal. Hey, I'm not greedy, if he wants I'll sell them to Richard for $40 and everybody will be happy. My point is these guys offer to sell us their stuff and their ideas, we try and educate ourselves and buy what is best for us.

I agree with you on that one, we do pay for someones ideas. I guess I shouldn't be so biased.

 

[Mark Craig]

daytripper63,



No the Walbro does NOT do anything but pump fuel. The air removal is a benefit especially for the CR trucks as pressures are higher and the injectors are more suspectible to damage etc.



Mark @ DPPI