Cylinder Balance with ICT?

Discussion in 'PSI Superchargers Tech Questions' started by Bjs344, Nov 11, 2017.

  1. Bjs344

    Bjs344 Member

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    SSI F3 on a BBC. 1 to 8 are only a few numbers apart except for #3. I'm 6 sizes bigger nozzle than the next biggest and it's still almost a thread hotter and squishing the bearing every few passes. I have a grid but have never used ICT. Is this a common way to fix a hot hole?
     
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  2. rb0804

    rb0804 Active Member

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    I know guys that pulling timing or run different rocker arm ratios or different length rods in cylinders that don’t behave like they are supposed to. Are you mechanically injected or electronic? You have a standard firing order? Is there something in the intake manifolding that may need a little fixing?
     
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  3. Bjs344

    Bjs344 Member

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    4/7 swap. Mfi. Just put all new hoses on a couple races ago (thanks Will!).

    Must be the intake/blower but I don't see anything obvious.

    Is a rod or rocker change safer than ICT??
     
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  4. MaineAlkyFan

    MaineAlkyFan Active Member

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    Did the issue pre-date the hose swap? We had a 'line tests fine' hose with a pinhole on the inside jacket. When it saw full pressure, the fuel would get between the inner & outer jacket and balloon the line internally. Line looked fine on the bench but during the run it was internally restricting.

    Chris Saulnier - Team Tigges
    Mechanic Falls, Maine
     
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  5. Ron C

    Ron C Jr. Dragster

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    It could also be an issue with the fuel distribution block which I have found from time to time. Try swapping two lines at the fuel block and see if it moves.
     
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  6. rb0804

    rb0804 Active Member

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    I don’t think one is safer than the other, just a preferred way of doing things. Pulling a couple of degrees from that hole is perfectly fine and lots of people do it. Just verify that it is actually doing what your telling it to.
     
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  7. Bjs344

    Bjs344 Member

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    The problem predates the line swap. I went through my notes and I've been putting 1 or 2 numbers in this cylinder for awhile now.


    I also didn't intentionally keep the same lines on the same port of the dist. Block, but changing/checking the block is certainly worth a try, I hadn't thought about that at all.
     
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  8. jody stroud

    jody stroud ZOMBIE Top Dragster

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    On my MBR I run a 100 shorter rod on number 3 and take some off the top of the piston.
     
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  9. Ron C

    Ron C Jr. Dragster

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    I've run into the fuel block distribution problem twice in the last couple yeRs. Once on an Nostalga A/Fueler and also on mine.
     
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  10. TOL

    TOL Active Member

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    Is there anything weird or different about your particular cylinder #3 physically? Previous repair? Sparkplug threadsert? You say the problem pre-dates the recent line change, by how long and what else changed before the lines?
     
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  11. Bjs344

    Bjs344 Member

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    Good call on some things you mentioned. I think I will take a closer look at spark plug depth and maybe repour each chamber, not sure I did that after the last repair.
     
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  12. Mike Canter

    Mike Canter Top Dragster
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    As TOL if you have a plug insert thread repair in that hole the spark plug will read hotter because it cannot transfer heat as fast through the insert.
     
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