bladz311

iTrader: (1)

Ok, I am installing a GT40R BB single turbo and a direct port wet nitrous system. How do I run 2 fuel pumps for this? I want to maybe run 2 Walbro GSS-341 fuel pumps (pretty sure thats the 255 lph pumps). Do you think they will work? I'm not going to be boosting over 18 lbs of boost and only using the n2o for the track. How do I run the lines? Y them together or run 2 seperate lines? What all will I need for this setup? Should I run one fuel pump just for the n2o and use a larger one just for the engine? Sorry for all the questions, I'm just confused.

bladz311

iTrader: (1)

I was thinking about running 2 walbros with maybe a 6 or 8 an line Y'd into a 10an to the fuel injectors/n2o. What do you think? Will that supply enough?

shawnk

Start reading here....

https://www.rx7club.com/showthread.p...hawn+fuel+pump

Shawn

shawnk

BTW that electronic piece fatboy7 made for me did not work exactly right and while testing it I discovered that I can tell when one pump is not working just by my pressure gauge and idle so I am not using it. There is nothing you can do about a pump going out at WOT so my main concern is that I would lose the pump and keep driving until I blew my engine but it is very easy to tell when one is not working.

I am getting ready to do my fuel system for the 4th and final time in a couple weeks and here is how I am going to do it.

2 pumps in tank like this (minus the stuff on top of the assembly - I will be moving that fuel block inside tank):



But I wont be using stainless in the rear of the car this time. I am going to order some high end non-stainless hose from summit. I will be running a hose from both pumps to one Y from a moroso (sp?) kit I got off of summit. From there it will be a 8AN line to a 8AN filter. Then Y them back apart and come out of the tank with 2 6 AN feed lines. One to the stock feed hard line that runs under the car, and the other to the vapor hard line (which I am no longer using for vapor). Then from the front hard line directly to each rail seperately and from the rails to both sides of a 1:1 fuel pressure regulator. Finally a 6AN return to the return hardline and then from the rear to the tank. This way I have as few fittings (possible leaks and very expensive when you start adding them up) as possible in the system outside the tank. And I am putting the Y's in the tank so if there is any problems with those leaking it wont be a problem (cuz it is in the tank )

Now this is just the way I am going to do it and who knows if I'll be happy with it because I have done it 3 times before and ended up being disappointed with those plans. If you want to wait a month I will be glad to tell you how it works out.

Shawn
www.3rdgenrx7.com/index2.htm

bladz311

iTrader: (1)

Awesome, I'm going to do almost that same setup, except run some steel braided all the way up from the tank to the engine bay. I spent like an hour making a bracket to hold the second fuel pump (it was almost a copy of the stock bracket), but I didn't think about the bracket for the plunger... well it didn't fit. I gave up on the bracket after that and just hose clamped them together like you did, haha. Thanks for the help. Sorry I didnt reply back sooner.

Marcel Burkett

I recently rebuilt my fuel system , here is what I did ..., I made a bracket using four T bolt clamps and a piece of flat stainless steel sheeting to hold the twin BOSCH '044 pumps side by side (they are external pumps) , I also used separate AEROMOTIVE filters on each suction , the size of the suction lines is -10AN , from the pump I used -8 AN hoses which were Y'd together using a NOS Y fitting, from there it goes to the front through a -10 AN supply line. Using a T , I split the -10 supply line into two -6AN lines to feed the rails, I have three rails , two are fed in series from one -6 line , while the other (which holds the 1300cc injectors ) has its own supply.After the three rails , two -6 lines go into my PAXTON 1:1 reg , from where it flows back to the tank through another -6 line.
I opted to use cotton braided rubber hose from the rear to the front because I run it inside of the plastic ducting / housing thing that houses the brake and fuel lines , I also have the 0 gauge power cable (I relocated my battery to the hatch) in there too , so I did not want to risk any chafing of my brake lines or power cable by the ss braid.
One question though , I read somewhere that the pumps should be wired separately through separate relays , I have mine wired in series using 8 gauge amp wire for both power and ground and a single 40 amp relay which switches the power . The pumps are rated at 15.5 max amps so I am using a 30 amp inline fuse on the power , I hanven't seen any problems with this set up so far , I think the twin relays is overkill but I dont want to be under supplying the pumps with power , what do you guys think ?.

bladz311

iTrader: (1)

I think that sounds good. I also relocated my battery, but I have my interior completly out, so I drilled a hole behind the heater box on the firewall and ran the wire that way (also ran all the gauges' wires in there and the nitrous supply line).
I'm going to Y the -6 an fuel lines coming out of my 2 walbros together, then run either a -8an or a -10 an up to the front. Then I'm going to use a Y so I can run the 2 fuel rails in parallel (probably with -6an) then back into my aeromotive FPR and use the stock -6 an fuel return line. Also I'm going to hook the wet nitrous supply up at the Y before the fuel rails to make sure it gets enough. I am also going to run 2 relays with 2 power supply lines to the fuel pumps, but not in series, in parallel (just in case one fuel pump would give out).

That sound good? You can tear it apart if I'm being stupid.

shawnk

I did the twin relays. Bypassed the variable stock setup so the pumps were on high all the time.

I am still trying to imagine a 10AN line for your feed - that is huge! You have a 10AN line, a 6AN line and a huge electrical cable in that channel Marcel?

I ended up taking the Y in the engine bay out and ran the lines in series - secondary first, then primary, then back to paxton fpr. I didnt like having those fittings in the engine bay as one of my weaknesses is plumbing - every thing I do that is plumbing related seems to leak so I just try to minimize the fittings.

The problem I kept having was sealing the hole where I ran the extra wiring through in the tank. What did you use bladz311?

Shawn

c00lduke

Shawnk, is there anyway you ould explain you twin relay setup inorder ot make it run on full all the time?

Marcel Burkett

I may do the twin relay thing , but I plan to check the voltage at my pumps first , if its good I may not bother.
Yes the -10 line and the thicv 0 gauge electrical cable fit in there together with all the other lines.