Results 1 to 16 of 16

Thread: E39 Twin Intank Fuel Pumps

  1. #1
    Join Date
    Sep 2010
    Location
    Cordova, TN
    Posts
    437
    My Cars
    One day it will be done

    E39 Twin Intank Fuel Pumps

    Has anyone successfully found a way to mount twin intank fuel pumps?

    I've been scratching my head on this for a few days now and figured I would see if anyone has attempted it.

    Trying to avoid running a surge tank and external pump. Discreet is key here.

    As always, any opinions or help is appreciated.

  2. #2
    Join Date
    Nov 2009
    Location
    Long Island, NY
    Posts
    5,346
    My Cars
    67mm 325i, RAM 1500
    Unfortunately i have no clue what the e39 setup looks like, any idea on power goals? A single in tank pump can make anywhere from 650-720whp on e85 and over 900whp on gasoline.

    You might have to get creative with a dual pump setup, just remember if they are on at all times you will be heating up the fuel and your return line has to be like a -10

  3. #3
    Join Date
    Sep 2010
    Location
    Cordova, TN
    Posts
    437
    My Cars
    One day it will be done
    At the moment I am still debating on single or not. This started as a simple 600-700whp goal and seems to be growing towards the 800-900hp range. Unfortunately meaning more $$$

    I would like to over build the fuel system so there is plenty of room to grow. Bigger is better right?

    From the way the pump is setup in the e39 it doesn't seem feasible in my mind to fit two pumps. Hence this thread.

    Even with a single pump, getting a big enough fuel line to the sender is going to be a task. The sender is a very tight fit below the body. After a few hours of research, I couldn't find any real substantial e39 fuel system upgrades. So if we do find a way I will make sure to document. Worst case I will put a surge tank in the spare well.

  4. #4
    geargrinder's Avatar
    geargrinder is offline Having No Trouble Here BMW CCA Member
    Join Date
    Mar 2010
    Location
    AndoverRockport MA & Intl
    Posts
    14,803
    My Cars
    E46M3Cic E39.540iT E84X1
    Quote Originally Posted by DustinDTM View Post
    I would like to over build the fuel system so there is plenty of room to grow. Bigger is better right?
    Not really. E36hateR nails it. Overbuilding the fuel system by huge margins is dumb although it sure seems like everybody gets the "bigger bigger bigger" bug just like for injector sizing "just in case I can possibly at some point violate the common engineering principles and rules of physics and make magical levels of power". Anyway...

    But if you are truly at the limit of what a single in tank can do, esp if you are running E and going to have to shift a lot of volume, that's a whole different story, and yeah I would probably do surge tank in the trunk as the first option.

    We've just been going over this in E39 threads for non-big-power SC setups. It seems even a 'standard' aftermarket 340LPH pump overwhelms the factory FPR and return lines. So you'll need to rip out and fab new return and FPR setup. Which isn't that hard, but it's all necessary to so you can pointlessly recycle all that hot fuel ;^P .

    The tank does have that dual senders setup so the other option would be to try to put a pump in each side in parallel using the 'sender-only' side for another fuel basket. I have no idea if that would work or if the internals of the tank would interfere with that. And it'd be anybody's guess if the fuel level senders still worked properly in that config but if you were super lucky it would all be plug and play. If I was to try that I'd still probably want to run them to a common surge tank. By doing that it might solve your concern with what you call "sender" by which you really mean "supply line fitting" ("sender" is the level sensing apparatus)
    2003 M3CicM6 TiAg
    2002 540iT Sport Vortech S/C 6MT LSD TiAg
    2014 BMW X1 xDrive28i (hers)
    2008 Audi A3 2.0T DSG (soon to go on the block)
    1999 Cherokee Sport 4L (trailer-hitched in-law-loaner bomber)


    Former:

    1985 Euro 300SL
    1995.5 Audi S6 Avant (utility/winter billetturbobattlewagen)


  5. #5
    Join Date
    Sep 2010
    Location
    Cordova, TN
    Posts
    437
    My Cars
    One day it will be done
    I feel like it will be right at the limit of one intank. The thought was to add a second one on a pump controller. It's not like I was asking should I install 3 pumps on a mild s/c with 100lb/hr injectors. Hence "dumb" .

    I was just asking to see if it had been done. Not opinions on what should be done. The last post seemed very condensending. But, I appreciate the input gentlemen.

  6. #6
    geargrinder's Avatar
    geargrinder is offline Having No Trouble Here BMW CCA Member
    Join Date
    Mar 2010
    Location
    AndoverRockport MA & Intl
    Posts
    14,803
    My Cars
    E46M3Cic E39.540iT E84X1
    LOL. I love the old "you are not allowed to have opinions that I may not like in my thread".

    But I wasn't casting stones at you as much as people who massively overbuild fuel systems for no reason except bragging bling, and I thought I made it pretty clear (2nd paragraph?) that if you do need it hey you need it.. and then I gave you a pretty solid suggestion, being as helpful as hell if I do say so myself. So lighten up there Francis.

    But it is true our threshold of dumb is clearly different. I would draw the line way before your ridiculous 3 pumps on a mild S/C example. I would say even one massive pump on mild S/C is dumb unless the math proves the need for flow and you are nearing the limits. Again, you're just heating fuel and sending it around the car for no reason. And again if you really are at these high levels of power and flow, then more power to you. You really should look into the 2nd sender cap thing.. Might be worth sourcing a cheap junkyard gas tank to play with to mock up the system on if you know anybody parting a car. Could be a nice tidy system. Could even put it on a switch for running E for instance... run single pump when you are driving around on pump then flip to the E tune and turn the second pump on when you have the real juice...
    2003 M3CicM6 TiAg
    2002 540iT Sport Vortech S/C 6MT LSD TiAg
    2014 BMW X1 xDrive28i (hers)
    2008 Audi A3 2.0T DSG (soon to go on the block)
    1999 Cherokee Sport 4L (trailer-hitched in-law-loaner bomber)


    Former:

    1985 Euro 300SL
    1995.5 Audi S6 Avant (utility/winter billetturbobattlewagen)


  7. #7
    Join Date
    Sep 2010
    Location
    Cordova, TN
    Posts
    437
    My Cars
    One day it will be done
    I may have jumped to conclusions on the whole condensending thing. Been a shitty morning and I may have taken it the wrong way.

    Apart from that. Adding a pump to the second hanger is a good idea. I happen to have a spare tank available

  8. #8
    geargrinder's Avatar
    geargrinder is offline Having No Trouble Here BMW CCA Member
    Join Date
    Mar 2010
    Location
    AndoverRockport MA & Intl
    Posts
    14,803
    My Cars
    E46M3Cic E39.540iT E84X1
    Nawww you're probably right. I'm 1/2 douche 1/2 A-hole most of the time. No worries. Spare tank that's great!
    2003 M3CicM6 TiAg
    2002 540iT Sport Vortech S/C 6MT LSD TiAg
    2014 BMW X1 xDrive28i (hers)
    2008 Audi A3 2.0T DSG (soon to go on the block)
    1999 Cherokee Sport 4L (trailer-hitched in-law-loaner bomber)


    Former:

    1985 Euro 300SL
    1995.5 Audi S6 Avant (utility/winter billetturbobattlewagen)


  9. #9
    Join Date
    Nov 2004
    Location
    San Antonio
    Posts
    6,019
    My Cars
    Z3M Coupe & Roadster
    I think Technica had/has a E39 M5 with a 2jz stroker but I think they are running one large fuel pump. You can call them and check to see if they have anything they can share on it.

  10. #10
    Join Date
    Feb 2008
    Location
    Upstate
    Posts
    683
    My Cars
    2 Boosted,1 more left to
    I know when Eshift did 930chas and my 2jz swap they added the 2nd pump on a bracket next to the 1st fuel pump basket. I will try and dig up some pictures because I have changed to just one 416 walbro with -8 feed
    Last edited by 1NAWTY5; 06-03-2015 at 04:52 PM.

    E39 LSX SWAP PARTS FORSALE


  11. #11
    Join Date
    Sep 2010
    Location
    Cordova, TN
    Posts
    437
    My Cars
    One day it will be done
    Quote Originally Posted by 1NAWTY5 View Post
    I know when Eshift did 930chas and my 2jz swap they added the 2nd pump on a bracket next to the 1st fuel pump basket. I will try and dig up some pictures because I have changed to just one 416 walbro with -8 feed
    That would be great. Thanks!

  12. #12
    Join Date
    Jun 2012
    Location
    Richmond VA
    Posts
    448
    My Cars
    1998 M3/4/5
    Is the hat itself anything alike the e36 hat? if so, this may be able to be made to work fairly easily..

    http://www.rallyroad.net/content/ral...el-pump-hanger

    at my old company we made a very similar product, for mopars, but it was the same concept. Of course they're system supported larger pumps but I don't see why you couldn't fashion a larger pump in the rally road kit if you wanted to.

    http://www.shophemi.com/p-2535-compe...-fuel-hat.aspx

  13. #13
    Join Date
    Sep 2010
    Location
    Cordova, TN
    Posts
    437
    My Cars
    One day it will be done
    Quote Originally Posted by Apex24 View Post
    Is the hat itself anything alike the e36 hat? if so, this may be able to be made to work fairly easily..

    http://www.rallyroad.net/content/ral...el-pump-hanger

    at my old company we made a very similar product, for mopars, but it was the same concept. Of course they're system supported larger pumps but I don't see why you couldn't fashion a larger pump in the rally road kit if you wanted to.

    http://www.shophemi.com/p-2535-compe...-fuel-hat.aspx
    Unfortunately the e39 hanger is completely different. The actual pump sits in a "basket" in the bottom of the tank and has no other connection to the hanger other than the supply hose and wiring.

  14. #14
    geargrinder's Avatar
    geargrinder is offline Having No Trouble Here BMW CCA Member
    Join Date
    Mar 2010
    Location
    AndoverRockport MA & Intl
    Posts
    14,803
    My Cars
    E46M3Cic E39.540iT E84X1
    DTM did you have any luck peering in at your spare tank at the sender-only side to see if a pump-basket-side rig will drop in there?
    2003 M3CicM6 TiAg
    2002 540iT Sport Vortech S/C 6MT LSD TiAg
    2014 BMW X1 xDrive28i (hers)
    2008 Audi A3 2.0T DSG (soon to go on the block)
    1999 Cherokee Sport 4L (trailer-hitched in-law-loaner bomber)


    Former:

    1985 Euro 300SL
    1995.5 Audi S6 Avant (utility/winter billetturbobattlewagen)


  15. #15
    Join Date
    Sep 2010
    Location
    Cordova, TN
    Posts
    437
    My Cars
    One day it will be done
    Quote Originally Posted by geargrinder View Post
    DTM did you have any luck peering in at your spare tank at the sender-only side to see if a pump-basket-side rig will drop in there?
    Unfortunately not yet. I should have some spare time this weekend to grab the tank out of storage and get it open.

  16. #16
    Join Date
    Oct 2018
    Location
    Southeastern CT
    Posts
    19
    My Cars
    1997 528i Auto
    I know it's an old thread, but I've seen you've been active in 2019.
    Did you ever have a chance to try this?

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •