AirDog, AirDog with Raptor, and FASS users, question on setup

hpprose

hpprose

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Ok, I need some help.

I have a friend how just purchased the new Airdog setup. He is also replacing all of the lines on the engine and getting ride of the fuel bowl. For those that are using one of the above mentioned fuel pumps, how are you plumbing it? I have an Aeromotive with an external regulator and I know how that is plumbed. I’m asking only those with an internally regulated fuel pump.


Pick Up tube to Pump w/filters
Pump to y-adapter
y-adapter to front of cylinder heads
(so no return line?)

or

Pick Up tube to Pump w/filters
Pump to y-adapter
y-adapter to front of cylinder heads
Return line from back of cylinder head to a different y.
y to return


I would assume the first way is the better way to plumb, but not sure.
If no return line, where are you capping the factory return line at?
 
If you go with the second route, install a needle valve after the "Y" on the return lines, that way you can restrict the return flow, which will still permit the FASS, or AirDog, to return the "air/fuel" mixture it needs to, and maintain cool fuel to the heads at all times. (If you just connect the back of the heads together, the fuel is heated up by the exhaust up-pipes, the turbo, and the block.)
I also installed a 10 micron Aeromotive Platinum filter after the pump, and before the first "Y"....and a huge fuel cooler after the second "Y", and needle valve. (cools the fuel before dumping back to the tank) And lastly...I installed a 1 psi checkvalve in the return line, close to the tank, to prevent the return line from syphoning any fuel out of the heads when the engine is shut off.

Hope that helps you out.:Cheer:
 
the airdog has built in regulator...need to make sure to use the right spring and washer to shim it to the correct pressure....it also has a return line...this is how i did mine in a nutshell...

bigger pickup tube
pickup to suction side of airdog
return line back to the tank
discharge line down the framerail up to under the hood
going into a cross
one side of the cross is where the feed comes from
one for the fuel pressure sender
other(s) for fuel feed lines to the heads...
also the main feed line from the pump is 1/2" as supplied with the kit, but when i split off into the 2 lines feeding each head i used 3/8....if you split with 2 - 1/2" lines then you are increasing the inside diameter of the lines and allowing for a larger pressure drop, so anytime you Y off or split the line you need to go down a size to allow pressure to be constant!

with my setup it idles at 52-54 psi and drops maybe 2 psi wot with 180cc injectors and with stock injectors drops 0-1 psi!

I also completeley deleted the stock fuel system...HCFM, fuel bowl under the hood, all lines, etc.

let me know if you have any other questions, need more info, or pics...
 
6L strokin said:
the airdog has built in regulator...need to make sure to use the right spring and washer to shim it to the correct pressure....it also has a return line...this is how i did mine in a nutshell...

bigger pickup tube
pickup to suction side of airdog
return line back to the tank
discharge line down the framerail up to under the hood
going into a cross
one side of the cross is where the feed comes from
one for the fuel pressure sender
other(s) for fuel feed lines to the heads...
also the main feed line from the pump is 1/2" as supplied with the kit, but when i split off into the 2 lines feeding each head i used 3/8....if you split with 2 - 1/2" lines then you are increasing the inside diameter of the lines and allowing for a larger pressure drop, so anytime you Y off or split the line you need to go down a size to allow pressure to be constant!

with my setup it idles at 52-54 psi and drops maybe 2 psi wot with 180cc injectors and with stock injectors drops 0-1 psi!

I also completeley deleted the stock fuel system...HCFM, fuel bowl under the hood, all lines, etc.

let me know if you have any other questions, need more info, or pics...
Click to expand...

so you run option 1

Pick Up tube to Pump w/filters
Pump to y-adapter
y-adapter to front of cylinder heads
(so no return line?) with the return line at the fuel pump not at the head.
 
Extended Power said:
If you go with the second route, install a needle valve after the "Y" on the return lines, that way you can restrict the return flow, which will still permit the FASS, or AirDog, to return the "air/fuel" mixture it needs to, and maintain cool fuel to the heads at all times. (If you just connect the back of the heads together, the fuel is heated up by the exhaust up-pipes, the turbo, and the block.)
I also installed a 10 micron Aeromotive Platinum filter after the pump, and before the first "Y"....and a huge fuel cooler after the second "Y", and needle valve. (cools the fuel before dumping back to the tank) And lastly...I installed a 1 psi checkvalve in the return line, close to the tank, to prevent the return line from syphoning any fuel out of the heads when the engine is shut off.

Hope that helps you out.:Cheer:
Click to expand...

So, you are running the second way

Pick Up tube to Pump w/filters
Pump to y-adapter
y-adapter to front of cylinder heads
Return line from back of cylinder head to a different y.
y to return

With an additional fuel cooler, regulator and check valve.
 
First I will say I had a fass. I then went from the tank to the fass(-8 line). From the pump I did -8 all the way to the front and then y'd into (2) -6 into each head. I then came off the back of the head to (2) - onto a ragulator and then back to the tank. That was my setup. I bought all of it from Jegs. most of it was from Earls except the y fitting. It was from NX

Here is a picture of the y fitting. Its alittle dirty after I blew the up-pipe...What a mess
IMG_0142.jpg
 
My friend is getting everything from Trusted Performance. So, I’m not worried about where to get it, just how it should be run. The new AirDog is a stand alone fuel pump with an internal regulator. So, the Stage II kit from them comes with a regulator. So, when he orders it, I’m going to tell him not to get the regulator. I’m sure they are going to ask how he wants the stainless steel lines coming from the back of the head tied into the system.

They may already have a kit, I just don’t know. So, I figured I would ask first then have him order.

From what it sounds like, we should tie the stainless steel lines from the back of the heads to each other and cap off the return line. Adding the fuel cooler could be an interesting move.

Another option is to have the fuel come to the top of the engine into a 5 way block. Then feed both heads from both sides. Thoughts??
 
Another option is to have the fuel come to the top of the engine into a 5 way block. Then feed both heads from both sides. Thoughts??

I tried this already. That was way back when I called it "The 4 corner fuel system." I posted pictures on here, and other sites.
The problem remains...you have no fuel returning from the engine, and depending on how much fuel you are actually burning, depicts how much, and how fast it is replaced with cooler fuel.
The bigger the lines, the more volume, so now you have even more time for the fuel to heat up while waiting to be injected into the cylinders.
Think of what happens in the summer months when it's 100*F, and you are down to say half a tank...not much fuel is being returned...especially if you don't have a return line from the engine...now how hot is it under the hood...how hot is the electric motor on the pump?????
That's why I installed a "Y" from the back of the heads, covered them with insulated wrap, (Velcro style) and added a cooler.
And if you don't think you have enough pressure for racing...just close the needle valve before the cooler, and make the run...then open it again to the pressure you want.
 
The new Airdog system is not ready yet. Said they got the first batch in and they were not satisfied with it. That was a week or so ago, but they are gonna call when it is ready. How is it you run an Airdog 150 as a stand alone on a 6.0? I did not think it would seperate air if it is shimmed to push 5x the psi it was designed for.
 
I'm not running the new Airdog kit. I have a the Trusted Performance Stage II and III kit on my truck. My friend ordered the AirDog system but hasn't received it yet. He asked me to help him find the right engine kit for his truck.
 
6L strokin said:
the airdog has built in regulator...need to make sure to use the right spring and washer to shim it to the correct pressure.

Sorry, this is what I was refering to. He has an Airdog 150 shimmed to 50-60 psi?
Click to expand...
 
Any thoughts as to the pressure waves generated from the injector opening and closing?
 
PSDPlayer said:
Any thoughts as to the pressure waves generated from the injector opening and closing?
Click to expand...

I wondered about that a few times. Makes me wonder if a crossover line is a good idea? Wouldn't it end up sharing the pressure waves between banks? I added check valves awhile ago and just feed the front like stock, but have been kicking around returning it from the back.
 
hpprose said:
so you run option 1

Pick Up tube to Pump w/filters
Pump to y-adapter
y-adapter to front of cylinder heads
(so no return line?) with the return line at the fuel pump not at the head.
Click to expand...

correct...when you run a pump with its own return line its not really nec to run a regulated return in conjunction with it....maybe just a crossover line in the rear or something...
 
I mean there is a wave attenuation device in the rails for the oil. Check valves for the oil. And there were check valves for the fuel originally. I'm just curious to the reason it was found necessary to have them. I'm all for modifying the system. The 6an fitting matches the internal port in the head. But remember that the port in the head is offset to the injector hole so its not like you get a full .375 diameter to the injector.
 
And there were check valves for the fuel originally.

That is why I put check valves back in mine(+ I had way 2 much time on my hands). Only thing different was my f.p. gauge had a little fluctuation at idle, and afterwards it is steady. No noticable performance change.
 
PSDPlayer said:
And there were check valves for the fuel originally. I'm just curious to the reason it was found necessary to have them.
Click to expand...



Banjo bolts?
I think when the banjo bolt mod was being discussed guys were saying they were there to keep the fuel in the heads for startup.
Trucks seem to start fine without them.
Are they there for a different reason?
 
The loop in the new fuel lines to the fuel bowl was to keep the bowl from draining down.
 
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