I am looking into a new fuel system and am having an issue deciding on what pump to run. My setup would be 4x1000cc injectors and 2x360 cc injectors. I plan on running -8 line from the tank to the engine bay then "T" off the lines to -6 to each fuel rail then to a FPR then to the Stock feed line to use as the new return. Oh, and all of this will be flowing E85.

Now the simpleist way i would like to do it is install a Bosch 044 inline pump by itself. However i am not sure if this will flow the fuel i am looking for. I have read on different sites that you can have two of these pumps inline if needed. One in the tank and one inline, or you can have a Walbro 255 in tank and the Bosch inline. I happen to have a Walbro 255 in tank now so would running the Bosh inline with the Walbro 255 be the way to go? How can the Walbro flow enough fuel to feed the Bosh pump if the fuel has to flow through it to get to the Bosch. Also, could i jsut take the Walbro out and only run the Bosch inline pump and have adequite fuel?

OR


Should i just pony up the cash and get a a1000 which i htink would be a little over kill but i know would get the job done?

On a side note, does anyone have any fuel filter advice with whatever pump setup i go with. Thanks for the advice guys.

 

One of the challenges is getting things to fit in the available room The area where the fuel rails fit is tight...and try to use stock Denso injectors for primaries.......they fit well with no problems...others are not so fun

I used an Aeromotive FPR and a Canton Racing 1 micron fuel filter..and he stock line for the return to the tank

The fuel pump thing is more complicated...I think Walbro or Denso Supra pump would flow enough for up to 400whp..after that you are needing an 044...and a swirl pot or something to feed it

Read up on the "left hand turn fuel cut" issue and see what you can come up with that works in that scenario as well if you plan to track the car

 

End goal is 15lbs on a Precision 6265 (i think) running E85. I figure it will be right at 400whp so thats why i am wondering about the fuel pump issue. Your thoughts is that one 044 will do it without an issue?

 

The issue will be getting fuel to the pump out of the tank....there are some pickup issues with this tank setup

What kind of fuel flow do you think you will need..and work back from there

 

I read that the 044 can be ran inline with a Walbro 255 in tank. If this is true, how can the Walbro feed the 044? Also, if you decided to go wiht the swirl pot, could the Walbro feed the pot, then the 044 run inline after said pot? I am pretty sure i have it all figured out except for the pumps.

 

The pickup i figured there woudl be two ways. One would be if i left the 255 in the tank it would obviously act as my piccup. The second - there are fittings to tap the top of hte fuel tank assempbly once the actual pump is removed. From the tapped fitting a pickup tube is ran down to where the bottom of the stuck pump would have been. Those are the two optioins i have seen.

 

ok check my math here.

4760cc/min for total injectors (injectors would never run at 100% i know)

4760cc/min = 4.76L/min

4.76L/min =285.6L/Hr

Bosch 044 flows 300L/Hr


So one Bosch would flow enough fuel for 4 x 1000cc injectors and 2 x 380 injecrors correct?

 

depending on what pressure is needed.
Are you converting to a return system?
What did the 3 rotor guys end up doing? There may be some good info there for you in reference to flow requirements/problem solving.
For e 85 running --doesnt that require a different pump with seals etc that will tolerate e 85?
Will you not need a water seperator?
E85 is new territory but really interesting.

oops sorry I reread your 1st post---you are going with a return system.
With such high flow requirements and the way our tank/system picks up fuel, I would consider an in tank sump bladder?
OD

 

Bosch 044 runs 300lph at 94psi - - not sure how to look at psi to flow? obviously it would be ran at a lower psi so i am assuming that one bosch 044 will not flow enough fuel?
Yes, it will be a return system.

I have no clue about said 3 rotor guy - may need to do osme research there

most pumps on the market today will tolerate e85 wiht no issue. i know of a few people running E85 with the 044 without an issue and several domestics running the a1000 with out an issue.

No extra parts needed in the fuel system to run E85. Just need to make sure there is enough pump,line, and injectors to flow all the fuel needed.

 

could you elaborate on why you think a bladder would be needed please. Not sure of your theory behind useing one.

 

l/hr @60 PSI = 300/94*60 = 191.5 l/hr

Correct?

 

All things being equal it will flow more at 60 PSI...so no

 

would it not be easier to pull the oem tank and get an aluminum one fabbed up in its place?
then pumping selection would be easy, then buy a kgparts fuelrail or sumthing?
then mount an anti-surge/swirl out in the engine bay (in the airpump location if its deleted)

 

I am lost on why everyone is saying to replace the stock fuel tank. To me, i dont see a reason why. Especially if your going to use a swirl tank. Which i am not sure yet. Its a tank, and it holds fuel.

 

its a pick up issue. the location of the fp in the oem tank is in the worse possible position for performance. the oem system at times relies on a venturi pickup to balance the tanks/keep the cup filled.
You will be sucking serious volume in comparison to the oem rx8. Pick up may become critical at anything less than 1/2 tank?
Since you are shooting for 400hp--i take it you dont want any starvation issues?
OD

 

So to put a swirl tank inline you would need a pump to feed the swirl tank and then an inline pump after the swirl tank to feed the fuel system correct? If an 044 was inline after the tank then what should i use to feed the swirl tank, another 044? or woudl the intank walbro 255 keep up with feeding the swirl tank with the 044 feeding out of the tank?

 

i just found a really good thread on this on the rx7 boards. Looks like my 255 i have in tank will feed a surge tank jsut fine wiht an a1000 feeding out of the tank. basically it comes down to i would have to be WOT for over 2 min in order to drain the surge tank and have a fuel problem. 2min is quite a bit of time for WOT.

Now i have the issue of finding a location for a surge tank. Only place in our car is in the trunk, nex tto the battery box. Not to big on that idea but it looks to be my only option really.

 

They do make a collapsible bladder- surge tank that fits inside the tank. Now whether it will fit ours i do not know--but you can give some fuel cell companies a call to see if they make something for you.
But with the mods you are doing--you probably would not mind a small fuel cell type surge tank in the truck?
OD

 

Na, i am thinking a small surge tank in the trunk next to the battery box with not be that big of an issue. Just ALOT more plumbing i have to do. Now i can not use the facctory feed line for my return either. Since i am using the in tank 255 i already have, that means the suction tube from the other side of the tank will still work just as stock correct? all i will have to do is run a return line from the FPR to the surge tank and then run one from the surge tank to the Fuel tank. I will have to tap the tank or maybe the plastic fuel pump housing for the return from the surge tank.

Also on a side note. I got looking at the thead about isntall ing a 255 in tank ans a drop in replacement. I have already dont this since it came wiht the esmeril kit. However, they talk on there about melting the pop off cap so it will nto come off the plastic unit. I never did this since it was never discussed when i installed my kit. Is this still going to be ok with out it melted on.?

 

should be.
od

 

good deal. And the siphon from the other side of the tank should work correctly. I shoudl jsut have to tap a return from the surge tank into the fuel tank and thats all I should need to do to the stock fuel tank itself.

 

Also, does anyone know the rules for running fuel lines and or fuel pumps in the trunk. Obvioulsy i am going to have lines going into the trunk for the surge tank, but it might be alot easier jsut to mount the fuel pumps/pump in the trunk also. Just curious if there is some kind of rule against this for the track. Strip and road racing. Dont want to do the work then not be able to run the car somewhere.

 

Just incase anyone was curious.

Both NHRA and SCCA state you must install a rear firewall constructed of 24 gauge steel or 20 gauge aluminum that seals off the entire trunk/hatch area from the rest of the car if you run ANY fuel related components in the trunk. Difference between the two materials comes down to price and weight. 24gauge steel is cheap, weighs 1 pound per square foot and needs paint. 20 gauge aluminum is slightly more expensive, but weighs .45 pounds per square foot and can be left bare.

The good part is, is i work in a sheetmetal shop and everything is readily availible where i can do this if needed. The bad part is, I really dont wnt to install a rear fire wall in my car lol. However, if i can not find a place for a sure tank and pump outside the car, i may have no choice on what to do and will have to build a rear firewall.

 

For E85 and stock fuel tank, don't go with anything less than a 255LPH in-tank and 2 Bosch 044 in parallel. Believe it or not though, going this route will cost just as much, if not more, then a fuel cell with a built-in 800 lb/hr (@60psi 12v) fuel pump, integrated baffling(no need for a surge tank), 90-ohm fuel level sender and 100-micron stainless steel filter!
Here's a photo of what the fuel cell looks like in the trunk, I'll post another of the finished product with fittings/lines later.

 

I am planning on the 255 in tank and the a1000 most likely. I was wanting to steer away from the fuel cell in the trunk cuz i wsa trying to keep the weight balance as close to stock as i could. Fuel cell in the trunk would be just as easy and a surge tank in the trunk though. I also have my battery box back there and would still like some trunk space in case i actually needed it for something lol. Its an idea though. Just dont know about that large of a cell in the trunk.