rrmedicx

iTrader: (54)

LOCATION, LOCATION, LOCATION... Where is this lovely piece going to hide?

With the AAM setup that I am running I am not happy with the fact that the tank goes backwards before the fuel goes forwards and have frequently thought about re-routing it somewhere more forward. Just have to take some time to plot that out. Curious what ideas you have come up with.

ttg35fort

iTrader: (2)

I think we are going to use large U-bolts or stainless steel straps. I originally designed it with mounting tabs, but the mounting surface is not totally flat. Using U-bolts or straps gives us more options for selecting the mounting points on the car.

ttg35fort

iTrader: (2)

On the plate where I put the yellow oval in the picture.

rrmedicx

iTrader: (54)

Only thing I am concerned with is space for you...keeping in mind that the swirl tank uses gravity feed to provide fuel to your extra in-line pump it must sit lower than the swirl tank. Let me know where you find space, as I may revise my setup too.

I thought about using the frame rail just in front of the OEM fuel tank.

rrmedicx

iTrader: (54)

This is the AAM design that I modified with additional ports to the outer edges like you.
Then I capped one of the extra center ports:


But this is the bracket they used.

rrmedicx

iTrader: (54)

This is the AAM guide on installing their product:



Both yours and mine have been modified but it gives a good idea of how it should basically work...

ttg35fort

iTrader: (2)

We already measured the tube in that location. Actually, that's why I reduced the size from my first design, which used a 4" x 4" square tube and would have held close to 3 L.

We are going to mount the fuel pump to the right frame rail, just above the main GTSpec Chassis brace. We are going to isolate the fuel pump from the rail and mounting screws using rubber grommets. That way, we can minimize the amount of noise heard in the cabin.

The attached picture shows the connections to the bungs. I have the fuel in and fuel return going between the internal baffles. That way, the center portion where the fuel out is located should fill slightly quicker than the external portions.

leeboyNY

iTrader: (21)

Alright, seems like we got all the plumbing experts in this thread, so my question is how would you setup the surge tank with CJM's twin fuel pump? A or B?(see pics) Also, is it better to put the surge tank closer to engine or fuel tank?

oorx7

Charles and I have been playing with the idea of surge cans for some time now. All surge tanks seem to have the main fuel pump(s) external from the surge can. Has any one seen a set up that utilize the main feed pump inside the surge can? I have some ideas on this but would like to here if this has been done before.

oorx7

I think it would be better to keep the amount of distance between the tank(pressureless pump) and the surge tank as minimum as possibe. The less resistance the this pump has the more it will flow. Another reason, I Personnally wouldn't want a tank of pressurized fuel in my engine bay of a car that is driven on the street.

Not sure on your drawing, but both pumps from our assembly would be run into the surge tank. I feel this is a little over kill to feed a surge can but should work.

ttg35fort

iTrader: (2)

I think either location A or B will be fine. Keep in mind you will need a fuel pump between the surge tank and the fuel rails.

Also, using two Walbros to provide fuel to the surge tank will probably be overkill. The fuel pressure will be very low assuming you have an overflow line back to the fuel tank. A single Walbro should be more than adequate.
Right now I have two Walbros active and one spare in a SPR tripple pump hangar. I am pulling that out and putting the stock fuel pump assembly back in with a single Walbro. I am also drilling some holes around the outside of the stock swirl tank to improve fuel flow into it.

phunk

iTrader: (21)

you will probably want to go back to a stock pump assembly if you are going to run the external surge can

ttg35fort

iTrader: (2)

We looked at mounting the surge tank along the right side frame rail right above the GTSpec chassis brace, but I would have had to go with a smaller tank. Instead, we are putting the fuel pump there and putting the surge tank where shown in the picture above.

GreenGoblin

iTrader: (6)

very nice good read in here

rrmedicx

iTrader: (54)

Terry, I think you would want to keep your pump as close as possible to the swirl tank. Reason being there is no pressure pushing the fuel in the swirl tank all that distance. I thought you might be creative and find a space along the fuel rail for both with the tank just slightly higher than the pump, but if I am understanding you correctly it seems like you want the tank rear mounted and the pump side mounted to the frame rail...I see potential problems with inertia. You make the car move forward and all of the fuel in the line going forward to the inline pump becoming stagnant and possibly even moving backwards = fuel starvation. Maybe I'm reading it wrong. Please clarify if u can.

Also drilling holes in the stock swirl may also lead to starvation in high G turns as the stock swirl tank would run dry just as easily as it would fill back up. I know what you are trying to do, but that portion of your plan may backfire on you. Leave the stock swirl alone. Just my .02

ttg35fort

iTrader: (2)

I'm strategically placing the holes .

In my track outing, I did not run dry in the turns, only on the long straights, but I ran dry even when I started with a full tank of gas. This indicates that the Walbro was sucking fuel faster than the one hole in the stock swirl tank can provide. Now, I was accelerating forward, but I think the swirl tank was immersed in fuel, its just that the one hole could not flow enough fuel to satisfy my motor's requirement. So I need more fuel flow in. But you are right, I don't want to lose it in the turns. For that reason I am going to drill holes in the lower front portion and maybe in the bottom or the lower rear portion of the swirl tank, not in the sides.

With respect to the fuel pump location, it should be slightly lower than the surge tank. Nonetheless, once the fuel system is primed, the only way air can get in there is if the swirl/surge tank runs dry. I don't think that will happen with the stock swirl tank modification (i.e., the holes) I am making and the in-tank Walbro. Further, the external in-line fuel pump I am going with has sufficient capacity to pull from the surge tank all of the fuel it needs, even through a 3 or 4 foot line. The SX and Aeromotive in-line fuel pumps do not need fuel pushed to them. They will pull what they need. Also remember that my fuel output from the surge/swirl tank is 10-AN, as well as my fuel filters and fuel pump. I am running fuel lines sized accordingly. The in-line fuel pump should have all of the fuel it needs.

When I get it installed I'll post pictures. Also, I will go to the very first NASA event that is scheduled after my re-build is complete. I'll post my results.

rrmedicx

iTrader: (54)

I am curious to see how you mount the pump. If it works out well for you, I may re-design mine to follow suit. Only because as I stated, I don't like the idea of fuel going backwards before it goes forwards. As far as functionality..it still works, but I do think it can always be made to work better.
Keep up the good work.

phunk

iTrader: (21)

Hmm how many guys with fi are road racing? Is there really a market for a specifically road race engineered fuel system? What's the max rwhp you guys think a dedicated track z could be run at?

leeboyNY

iTrader: (21)

I see... more complicated than I orginally thought. I plan to participate in time attack events and drift competitions this season and I wonder if a surge tank is really necessary for me.. I mean I can always run with a full tank of gas.. I rather loose few tenth of seconds in time attack than reconfigurating my fuel setup.

ttg35fort

iTrader: (2)

On pump gas without meth I was a little over 600 hp. But on the track I will be running lower boost. I'm thinking around 500 - 550 hp. Plus, I'll be running meth.

I have your fuel return system, and it is working great! I considered your twin fuel pump, but I liked the idea of having a backup, as well as the price of the SPR hangar. I even put quick disconnects between the relays and the fuel pumps so that I could change over quickly at an event should one Walbro give out, which they do from time to time. As I indicated, I have not yet tried the SPR hangar on the track, but it doesn't use a swirl tank (I probably should have done more research before jumping), and that makes me nervous.

I have had absolutely no problems on the street with the SPR tripple pump fuel hangar. Fuel pickup has been great and I have never had a problem. But I became worried about fuel pickup in high G turns. My worry may be meritless, but I would rather spend a little extra now rather than risk blowing a motor later. Don't get me wrong, all of the guys at SPR have been great to work with. They have answered all of my questions and spent quite a bit of time with me on the phone (especially Tim, he is a great guy!).

Also, as I have said before, relatively speaking, I'm an old fart. The whine of two Walbros became irritating to me. For a proper perspective, I had my dumps ported back into the exhaust to keep the noise down, and my exhaust selections have primarily been based on "which exhaust is the quietest to achieve my hp goals." So I may not be your typical consumer.

For these reasons, I decided an external swirl/surge tank was best for me. I think that if you can make an in-tank surge tank, that would be optimum. But, from an old fart’s perspective, please, please make a system that is quiet enough to be drowned out by the exhaust (I now have a Greddy Evo TT).

I’m going with what I have for this build, but future builds are likely to happen. I’m now addicted. This is one person’s perspective but, again, I may not be the average guy.

Edit: I have provided the drawings of my systems on here to help the community. I'm sure you are much more knowledgable than I, but if you want to use any aspects of my design, feel free to do so. As far as I am concerned, everything I post here is open source, although I will hold no responsibilty for any results, good or bad. That said, much of my design was influenced by feedback from other members herein who have unselfishly provided their input.