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  1. #1
    cjo632racing's Avatar
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    Timing and compression with the 51 cam?

    Ok I just got done putting in my new valves and Rude valve train upgrade, I am not lucky enough to have a 28 or a 29 cam yet, so I wanted to make sure my compression and timing sound correct. I got out my dial indicator and put #3 at TDC, I then put the cam locker in, lined up my marks and done. My compression was 120lbs full retard and 155lbs full advanced, does this sound about right? Will the 51 make as much compression as a 29? Also with the valve train upgrade (no aftermarket ECU yet) will I have to repitch to get 8100 rpm again? I have a 15/20 in right now, I have a 14/19 should I install that?


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    Moderator Snoman's Avatar
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    Quote Originally Posted by cjo632racing View Post
    Ok I just got done putting in my new valves and Rude valve train upgrade, I am not lucky enough to have a 28 or a 29 cam yet, so I wanted to make sure my compression and timing sound correct. I got out my dial indicator and put #3 at TDC, I then put the cam locker in, lined up my marks and done. My compression was 120lbs full retard and 155lbs full advanced, does this sound about right? Yes it does,Most 51 cams to my knowlage are set at 135 psi..IMO i would go with 140,thats just me...Will the 51 make as much compression as a 29? Also with the valve train upgrade (no aftermarket ECU yet) will I have to repitch to get 8100 rpm again? Very little if any I have a 15/20 in right now, I have a 14/19 should I install that?
    I would leave the 14/19 out until you see what the ski will do..See how it accelerates and what RPMS you pull with it..if your Rs are low and the ski has no acceleration then i would switch back to the 14/19....

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