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  1. #1
    wavedemonx's Avatar
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    Smile Change from race gas to pump gas

    hi' just wondering if anyone could give a idea on what i would have to change/do to go from race gas to pump gas, details of ski: gp1300r 2003 triple pipe, comp 150psi, setup for racing. will add more info just trying to get an idea. thank you


  2. #2
    billy's gpr's Avatar
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    after market heads are 145-150psi.......depending on timing nothing... http://www.4-tecperformance.com/inde...roducts_id=160

  3. #3
    wavedemonx's Avatar
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    cool so i should be right then to run ski on pump gas. cheers thanks

  4. #4
    Gus13letter's Avatar
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    Maybe I am missing something. You said you are at 150 for compression? Then you should be able to run premium 93 octane gas now. Mine is 150 with 3 degree keyway running premium. Save your money if you want a different head and find an already milled stock head or find a used stock head and have it milled.

  5. #5
    txgp1300r's Avatar
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    I have been running 150 psi w/ 3 deg key on a 1390 ported for a few years now on premium pump gas with no detonation problems.........I even ran it at mudbug on swamp gas from gro's 2 years ago.

  6. #6
    With the triples, it would have been built with an aftermarket ignition. You would need a pump gas safe ignition curve. Either a advent, [email protected], or msd if it is total loss. More info on the ski is needed. Your compression at 150 is safe with a proper ignition curve.

  7. #7
    krispaintballz's Avatar
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    With triples you have to ad 10% to the compression numbers to be safe because of the high rev and timing. Also running a 1300r on triples means he is running a stand alone ingnition like msd or running carbs. He might be running efi but I only know a couple of skis that did that. If it was a race ski I highly doubt the EFI. Either way it will put him in the race gas range. You can get away with using a 50/50 mix premium(93 pon)/race gas but i wouldnt go any lower.

    Bottom line add 10% to the 165 psi which would put him at least into 50/50 mix 93 pon premium/110.

    DO NOT switch your heads. These triples like to be at or around 150 psi. A lot bump to 180 or 200 because of the faster rev but it will hurt the free rev on top to get top rpm. But closed course racers really didnt worry about that because back in 2003 the only place you could rev out was either the first stretch or the back stretch. Or if you have a very open course.

  8. #8
    Moderator beerdart's Avatar
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    There pump gas is a much higher octane then ours and is rated in ROM only ours is rated Ron/Mom x2 and we also have corn in our fuel.

  9. #9
    krispaintballz's Avatar
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    Quote Originally Posted by beerdart View Post
    There pump gas is a much higher octane then ours and is rated in ROM only ours is rated Ron/Mom x2 and we also have corn in our fuel.
    I use Mon too, aviation lean octane rating, better measure of how the fuel behaves when under load, as its determined at 900 rpm engine speed, instead of the 600 rpm for RON.

  10. #10
    billy's gpr's Avatar
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    Quote Originally Posted by krispaintballz View Post
    With triples you have to ad 10% to the compression numbers to be safe because of the high rev and timing. Also running a 1300r on triples means he is running a stand alone ingnition like msd or running carbs. He might be running efi but I only know a couple of skis that did that. If it was a race ski I highly doubt the EFI. Either way it will put him in the race gas range. You can get away with using a 50/50 mix premium(93 pon)/race gas but i wouldnt go any lower.

    Bottom line add 10% to the 165 psi which would put him at least into 50/50 mix 93 pon premium/110.

    DO NOT switch your heads. These triples like to be at or around 150 psi. A lot bump to 180 or 200 because of the faster rev but it will hurt the free rev on top to get top rpm. But closed course racers really didnt worry about that because back in 2003 the only place you could rev out was either the first stretch or the back stretch. Or if you have a very open course.
    caltex vortexs 98,bp ultimate,and shell v power should be fine......v power is 100 octane the others 98....

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