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  1. #1
    isa alnoaimi's Avatar
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    maximum boost on sho motors

    i just discovered that my riva head gasket was blown , i raised the boost till 180 kpa that means 26 psi , i used a 109 VP race fuel .

    i was using a riva head gasket !!!

    note i have the data log .


  2. #2
    ksalles's Avatar
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    In my opinion and experience, the engine assembly, overall build and tune determine the tolerable boost levels.

  3. #3
    seen them box stock tolerate 26 around 9500 for a good while with a blower.how long it lasted depended alot on how often and long it was being pinned open.if you are running high boost recreationally adjust your riding style and turn things down a bit if you are going to be aggressive
    Last edited by FXSlowKroozer; 11-14-2014 at 07:49 AM.

  4. #4
    AWA MEMBER
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    Quote Originally Posted by isa alnoaimi View Post
    i just discovered that my riva head gasket was blown , i raised the boost till 180 kpa that means 26 psi , i used a 109 VP race fuel .

    i was using a riva head gasket !!!

    note i have the data log .

    Did you use the Riva cylinder head stud kit?

  5. #5
    isa alnoaimi's Avatar
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    Quote Originally Posted by JoeyDFZS View Post
    Quote Originally Posted by isa alnoaimi View Post
    i just discovered that my riva head gasket was blown , i raised the boost till 180 kpa that means 26 psi , i used a 109 VP race fuel .

    i was using a riva head gasket !!!

    note i have the data log .

    Did you use the Riva cylinder head stud kit?
    yes im using them

  6. #6
    isa alnoaimi's Avatar
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    i looked at my data and it appears that i was over boosting thats why my riva head gasket was blown , i do have a manual boost controller and a boost gauge .

    so im rising and lowering boost based on my boost gauge , last time when i rode my ski the boost gauge wasnt working , and i was raising the boost based on my feeling of the ski (BIG MISTAKE) .

    in the pic the intake manifold pressure is 290 kpa !!! that means 27.5 psi !!!

    thank god it was only the head gasket and nothing else was damaged

    Click image for larger version. 

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  7. #7
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    Your injector duty is high I don't like to go over 80% yours is 112 and lean at 12.9

  8. #8
    ksalles's Avatar
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    As Joey had mentioned, you need to get the afr more in check. I wouldn't suggest 12. anything for extended WOT runs with a turbo. The turbo will pull a load , even with richer AFR numbers. If you're doing recreational riding and some extended WOT runs, keep the afr in the low to mid 11's. You may suffer a few rpms, but you increase the life of your motor. Your duty cycle being 112% is not suggested either. Is this a result of your kpa levels being that high? Are they lower once you get your boost levels back where you're comfortable? As far as "over boosting", 27psi is far from what these motors can handle.

    Quote Originally Posted by isa alnoaimi View Post
    i looked at my data and it appears that i was over boosting thats why my riva head gasket was blown....

    ...in the pic the intake manifold pressure is 290 kpa !!! that means 27.5 psi !!!

    ....thank god it was only the head gasket and nothing else was damaged

    Click image for larger version. 

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  9. #9
    Leendert's Avatar
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    35 psi at 9600 on oem gasket with arp bolts all day. On a ski that I know

  10. #10
    SLAP~YA's Avatar
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    Quote Originally Posted by Leendert View Post
    35 psi at 9600 on oem gasket with arp bolts all day. On a ski that I know
    Jesus christ!

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