Fuel Injection Questions

Discussion in '1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-' started by madmike1157, Sep 8, 2013.

  1. I'm gonna build the intake manifold outta mild steel. Not open for discussion. I can weld mild steel,..I cannot weld aluminum. The intake will require extensive fabrication,..and the bends I'll need are way too easy to source in mild steel.

    Finding Bosch style injector bungs in mild steel,..also not a problem.

    The problem comes in the fuel rail.

    What I really, really want are individual supply lines like mechanical injection uses,..but the only thing anybody has, looks like an aluminum, self contained piece for an individual Bosch injector that is tapped w/ 1/4 pipe threads on top.

    This would be perfect,..if it only was made out of steel.

    If I use some stock rail off of an inline six,. (like the one on a 300 six) I'll have to cut and splice the thing down to fit my shorter six,...which means that there'll be rubber hose sections clamped between each injector. The potential for leakage is obvious,..but I think I can maybe put a small single flare, or bubble at the end of each cut to retain the hose clamp so the sectioned rubber wont blow off from the pressure.
    I think I'm gonna use 60 lb/hr injectors though,..is a stock rail up to that kind of fuel supply capacity?

    I know I can buy a 6 cylinder length un-drilled aluminum fuel rail that can be custom drilled and shortened accordingly,..but the problem is where do you have that thing drilled, where the end result is a perfectly smooth rail that will not tear up the injector O-rings?

    My last "custom drilled" fuel rails done by my local machinist left a rough finish, that tore up the o rings,..and I cannot go back to him for that reason. I just don't want to have to have him do something he's not used to.

    If I don't do the cut and splice thing for the stock rail, sending the rail away for custom drilling, is my obvious next path. Who has done this? how much did it cost?
  2. You might give aeromotive a call. You referred to their fuel rail stock that you can cut to size, I'd ask them how to do it the right way.
  3. Yeah you can buy the fuel rail stock in various lengths, could also give Chris Hemmeter a call owner of Behind Bars Race Cars he could make you a custom set easily...he currently make many different rails. I'd want a larger rail with the 60# in to make sure you have a volume of fuel at the inj at all times

    I'd make the mounts out of steel and weld them in, then bolt in the alum rail as needed. You can buy the cutter for an end mill to make the fuel injector connection

    Sent from my XT907 using Tapatalk 2
  4. The cut and splice of the stock rail can be simplified with a tubing swage tool.
    View attachment 124914
    See http://www.zorotools.com/g/00098764...kw={keyword}&gclid=CJS927bavLkCFejm7AodWTEAdg cost is $20 + shipping


    View: http://www.youtube.com/watch?v=NWKYYSrGJiE
    for a video on how to use the tool, and of the different tool types available.

    To swage the tubing, place it in a faring tool clamp die and crank down on real hard. Then place the swaging tool in the tubing and smack it with a hammer. Bingo! when you are done, The swaged tube will fit neatly over the plain tube. Use additional pieces of the tubing and swage them to build any length fuel injection rail you want. You can braze or weld it (steel tubing) or use MuggyWeld rod to aluminum braze an aluminum part.

    A little bit of the care and effort that I have typically seen in your work could make this a very nice looking and functional part.

    Muggy Weld is neat stuff, but somewhat expensive. All it requires is a Propane or MAPP torch to do the job.
    See http://muggyweld.com/super-alloy-5 and http://muggyweld.com/aluminum-ac-fitting-weld
    #4 jrichker, Sep 8, 2013
    Last edited: Sep 8, 2013