90 degree injector line fitting causing restriction?

Discussion in 'PSI Superchargers Tech Questions' started by srxspec, Jun 10, 2013.

  1. srxspec

    srxspec Member

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    I was told this weekend by several people that these Enderle 90 degree fuel line fittings are known for causing restriction and the 90 degree bend in them (they are drilled from both ends, no radius in the bend) can cause air bubbles to be created. Has anyone else seen this? These fittings make my hose routing much cleaner and compact, but if they are going to cause problems I will change them.

    [​IMG]
     
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  2. Mike Canter

    Mike Canter Top Dragster
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    It is a well known fact in fluid dynamics that an abrupt ninety degree bend will cause a fifty percent reduction in flow. I could never understand why they came out with them. If you have the whole system flowed with them then you should be ok. If you switch without flowing the system then the motor is going to run lean and the size of the port nozzle jets will have to be adjusted accordingly.
     
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  3. eli

    eli Banned

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    Thats the reason my system don't have them,
    This is something someone once said'
    forgot his name, :confused:

    ( DON'T CONFUSE THE FUEL!)
    ( ONE WAY IN, ONE WAY OUT!)


    http://www.youtube.com/watch?v=Rc8DNswFohA

    Before anyone says anything, think first, the rails,
    line's #8 are flood'ed with fuel



     
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    Last edited: Jun 11, 2013
  4. Mike Canter

    Mike Canter Top Dragster
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    Don't make any difference if a -8 line flooded with fuel a ninety degree abrupt bend reduces fuel flow. Same applies in airflow from your hat opening down into the blower. That is why spacers under the hat that move the opening further forward and straighten out the airflow make more power. If you start off with big enough lines and flow or tune the fuel system with sharp turns from the start then you will not notice the reduction in flow. If you suddenly change to any fuel fitting with a sharp bend and your tuneup is tuned correctly then you may go lean and damage the motor. If your tuneup is rich then you may go faster when you use sharp bend fittings and go lean, lol. This will result in you saying these fittings are better and everyone should use them.
     
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  5. B.DOUCET

    B.DOUCET New Member

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    It would depend on the nozzle jet size. If you have a very large single port setup with nozzle size above .070, it might cause problems. Jim at Enderle could tell you what the 90* fitting flows.
     
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  6. jody stroud

    jody stroud ZOMBIE Top Dragster

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    Mike with rage fuel systems changed my straight hoses to 90 deg nozzles when he re- flowed my system. On his flow bench it showed no diff in quality of fuel delivery. I had the same doubts but the 90 deg fittings make for a cleaner system. He also said the the right angle an fittings from xrp are the same way, even though they are drilled it made no diff over the bent fittings. We moved my blower back two more inches and it changed distribution but the nozzles were not a factor.
     
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  7. Mike Canter

    Mike Canter Top Dragster
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    You can say what you guys want but you can't change physics and fluid dynamics. It maybe less noticable in some cases but it is still happening. If the flow through the jet is way less than the flow around the 90* bend then you may not notice it as much but it is still there. It is just a bad design to use sharp 90* bends in fuel lines or air flow.
     
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  8. srxspec

    srxspec Member

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    I am using them on all of my nozzles. My idles are .042, 2nd stage is .060, and 3rd stage .072. Thank you for the information. Currently my tune up is pretty close using the 90 degree fittings, so I will likely keep using what I have.
     
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  9. eli

    eli Banned

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    Think that your system is creating air to mix with the fuel? mybe you are on to something, may be your turning you alky into nitro. LOL:D:D



     
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  10. jody stroud

    jody stroud ZOMBIE Top Dragster

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    That's what mike at rage said also Bill ,,as long as port nozzles are kept below 85 he never saw a diff in flow. He has run 90 deg fittings on fuel motors before.
     
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  11. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    nozzles

    The radiused 90 deg fittings I sell with my port line kits have no change in flow from straight to 90 lines. That was verified on back to back flow tests.

    I have always been told to stay away from the drilled 90 fittings.

    As far as "anything below an 85" .....I was told by a very reputable fuel system guru that a 75-80 was about as big as a -3 line would flow period. In other words, anything much over a 78 you get minimal gains in flow because you are up against the max flow of the line.

    You may get a little more flow if you are in front of the blower (into vacuum) vs into intake (into pressure).
     
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  12. eli

    eli Banned

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    Will i just made 16 (Enderli fittings) port lines, I checked them for size, and they were all differint' between 0.116 to 0.118
    That said i reamed them all to the same size, 0.135. I also belive that all the lines should be the same lenth (Friction causes heat in the fuel) longer the line the more heat,
    might be the same flow but not the same heat. I gess I think like the old lady that pissed in the sea, every little bit helps. lol:D
    Gene Terenzio Sr.


     
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  13. SoDak

    SoDak Active Member

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    Some people have said that those 90° fittings in the picture can cause air bubbles, I personally do not believe that.

    Do you think that is possible?
     
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  14. nitrowannabe

    nitrowannabe Member

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    The reason I got for the 90's was that they are safer. Less stress than straight rubber or bent , flared stainless. Billes, Rage, ERD, DMPE all seem to like the 90's on their systems now.
     
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  15. Mike Canter

    Mike Canter Top Dragster
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    A radiused 90* fitting like what Will is describing is far better than a double drilled fitting that has a sharp 90* turn with a sharp edge in the turn. Yes. it would be possible for a drilled fitting with a sharp edge inside on the turn to create small air bubbles due to cavitation IF the flow was fast enough across that sharp edge in the turn.
     
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  16. Bob Meyer

    Bob Meyer Comp Eliminator

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    Once Upon a Time.......

    A fellow named George wanted to put fuel into the head right above the valve because it had no place to go in the manifold, he used Kinsler 90* into the head.
    I believe it went very well for him, I remember him kicking asses of every TAD in the country at least once ! :p
     
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  17. hemi altered 378

    hemi altered 378 Blown Altered

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    you are right Bob.....they definitely kicked everyones ass at least once. man that car hauled....bare bones car....not even an extra zip tie.
     
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  18. kosky racing

    kosky racing Comp Eliminator

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    Fittings

    If the 90deg causes these problems why do some return fuel to the bottom of the pump???
     
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  19. Mike Canter

    Mike Canter Top Dragster
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    Because some people don't know any better. Fluid and air flow loses through and abrupt 90 degree bend is a known fact. Because people don't understand it or don't know about it doesn't change it.
     
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  20. blown375

    blown375 New Member

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    I have to agree with Mike that a hard 90* will cause a restriction in flow but as long as after the 90* it flows more than the nozzle it's feeding and doesn't cause a cavitation , what's it matter?
     
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