Fuel system trouble

Discussion in 'PSI Superchargers Tech Questions' started by drew556, Sep 16, 2017.

  1. drew556

    drew556 Member

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    ok guys I have a dead cylinder at idle number 7 is 180 deg at idle it warms up through the run but is 200 deg colder than the rest at the finish line and it's lazy to even get that high it's been doing it all year and we can't figure it out we changed cap rotor plugs plug wires dropped jet 5 sizes to a 63 from a 68 raised it to a 73 didn't change anything none of the other cylinders have a problem just number 7

    Combo is a 526 hemi veney 2.500 alky heads whipple a980 with built in injector 73 over drive

    Any suggestions would be great would a dribbler solve the problem or ???
     
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  2. Aussiebattlr

    Aussiebattlr Member

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    What plug gap do you run?
     
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  3. drew556

    drew556 Member

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    .018 plug gap ngk 10 plug
     
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  4. Mike Canter

    Mike Canter Top Dragster
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    How does the spark plug compare in color to the other ones?
     
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  5. Blown5402

    Blown5402 Member

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    Do you run a PSI style plate under your Whipple or just open to the intake? Thanks, Jim in TN
     
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  6. drew556

    drew556 Member

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    Just open to the intake I was wondering about a diffuser plate do I need one
     
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  7. Blown5402

    Blown5402 Member

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    I made a PSI plate of my own style and just moved the cold cylinders to 1 & 2. I run open under the blower now and just let colder cylinders act as my traction control until they heat back up pretty quick in the run. They will be back making power by half a second in the run. Hope that helps some-Jim in TN
     
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  8. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    Whipple huffing fuel out number 7? Ahh brings back old memories of the TAD crew member with the "Whipple towel" over number 7 pipe so it didn't huff fuel on the tire.

    I don't know what your port check is set to, but it's going to have to be 5-6 lbs to really see much of a change at idle on an egt from a nozzle change.

    With that in mind, you can put a check in that individual port nozzle and see if that helps clear it up. Basically let it idle on the stuff bouncing around the intake.

    It's a hard problem to fix since it is huffing the fuel from the blower back to that hole.

    Going back to check valves, do you have some of your hat nozzles on checks?
     
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  9. Mike Canter

    Mike Canter Top Dragster
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    Ran a Whipple on Adams car in Sweden and in Russia. Didn't have any checks on the hat nozzles and run the port check at 20 lbs. Did have a plate under it. Had no problems and it is still running ok. Never huffed or puffed out of #7.
     
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  10. drew556

    drew556 Member

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    No checks on the hat nozzle the port check is at 12 lbs so maybe need to raise that to 20 going to go through the fuel system tomorrow night and double check all my checks and barrel settings what plate should we run under it will a psi plate work or is there one for a whipple
     
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  11. drew556

    drew556 Member

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    Update... checked the race pack and sure enough at idle have about 2-3 lbs of pressure on the port nozzles checked the poppet vs fuel pressure poppet was about 4 lbs less than fuel pressure at idle hopefully this will fix it going to find out this weekend. Thanks for all the replies and help
     
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