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  1. #1
    My name is Sean and I am addicted to STXs smokeysevin's Avatar
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    Spark plugs for modded 15f

    I was just going to order the cr9eix plugs for my 15f project but I got to thinking, what plugs are used in the endurance kit? That kit is run at something like 14 to 1 compression, mine is at 12 to 1. Just wondering what yall thought.

    Thanks

    Sean


  2. #2
    I'd say go for a high speed run and kill the engine, pull the plugs and have a look at the insulator/electrode color. I'd then adjust the heat range if needed. Light tan color is good amd white is too hot, black is sooty. Generally Champion go up in number for increased heat range and NGK do the reverse. I'd lean towards a cooler plug for the plug readings if it were me, and you have a base line color from before the modifications for reference. Chances are the mods may have added a tiny bit more power so the internal temperatures should be similar along with the plug selection.
    Last edited by rotortiller; 10-11-2010 at 06:50 AM.

  3. #3
    RonJon's Avatar
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    Call up RIVA. They should tell you right over the phone. Idk if they are open on Sundays... 877-748-2926 OR 954-785-4820

  4. #4

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    Sean I think what I would do is take it for a run with the stock plugs in it, Keep the idling to a bare min. bring it back and check it. You might only have to go a step up in heat range. I agree with RonJon .. Riva has done enough testing to probably tell you right off.
    How long before you get it wet?

  5. #5
    My name is Sean and I am addicted to STXs smokeysevin's Avatar
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    probably wont be until the spring, the motor is done, I am just missing parts to put it in, hoses, cables, a few gaskets and a lot of sanding.

    Sean

  6. #6
    jmatak9's Avatar
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    Quote Originally Posted by rotortiller View Post
    I'd say go for a high speed run and kill the engine, pull the plugs and have a look at the insulator/electrode color. I'd then adjust the heat range if needed. Light tan color is good amd white is too hot, black is sooty. Generally Champion go up in number for increased heat range and NGK do the reverse. I'd lean towards a cooler plug for the plug readings if it were me, and you have a base line color from before the modifications for reference. Chances are the mods may have added a tiny bit more power so the internal temperatures should be similar along with the plug selection.
    I pulled my cr9eix plugs and the are amd white, what do you reccommend??

  7. #7
    Take the time to smile sirbreaksalot's Avatar
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    Quote Originally Posted by jmatak9 View Post
    I pulled my cr9eix plugs and the are amd white, what do you reccommend??
    What Afr's have u set your tune too ?

    Cause no amount of plug changing / reading voodoo magic can add fuel if they are white from being LEAN mixtures !!!!

    Waz

    P.s I run Cr9eix and they are a nice mud brown after my 5 min WOT runs.....11.9 / 12.2 Afr's

  8. #8
    jmatak9's Avatar
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    [QUOTE=sirbreaksalot;1574120]What Afr's have u set your tune too ?


    I was running 11.5 with 550cc injectors 43lb, but plugs were fouling after 4 to 6 hours, JW recommended going back to stock injectors and FP set at 48 lb. That's what I did and the ski seems to be running better, quicker acceleration. So maybe I should turn up fuel pressure a bit??

  9. #9
    jmatak9's Avatar
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    [QUOTE=jmatak9;1574140]
    Quote Originally Posted by sirbreaksalot View Post
    What Afr's have u set your tune too ?


    I was running 11.5 with 550cc injectors 43lb, but plugs were fouling after 4 to 6 hours, JW recommended going back to stock injectors and FP set at 48 lb. That's what I did and the ski seems to be running better, quicker acceleration. So maybe I should turn up fuel pressure a bit??
    going to put in some new plugs and turn up FP, should be ok

  10. #10
    JET250's Avatar
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    dont be guessing get an afr meter, but put it at 50 psi until you do. better to waste fuel and some plugs then cut a piston.

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