XPL Coffman build - 7760 rpm
- Thread starter seadooaddiction
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seadooaddiction
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Nope. I'm not running aggressive squish or timing really. The reflash in the mpem from novitec is for 93 octane.
seadooaddiction
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This appears to be the only casualty. I will still replace this pedal. That is if I can separate the manifold from the spacer as a result of my exuberant ultra black application.
seadooaddiction
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It's been a doozey of a beginning of the season. Had a piston meltdown due to lean condition caused by air leak. Got a new piston and had bore cleaned up with hone. Now that motor is back together for the 3rd time this season I took it out for a break in period. 1st time I got on around a right hander splines on the prop sheared right off.
Dang I'm sorry to hear that. Keep fighting the fight though you'll have it in a sweet spot soon.
seadooaddiction
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Thanks! My piston meltdown was the reason for my absence at the lake norman ride. I'm not discouraged from this one. The top end rebuild was more discouraging cuz it was brand new to begin with. Idk what it is but there's something that tickles my fancy that it sheared the splines. Too much power! (I wish) I keep finding myself laughing each time I inspect the splines.... pretty surprising.
seadooaddiction
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I put the motor back together with a thicker base gasket this time. Should help avoid any detonation.
seadooaddiction
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Good Luck! I assume you have to break everything in?
seadooaddiction
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Good deal. I'm swapping the prop back in that I had in the middle of last season. A previous post indicates I was turning almost 7650 rpm with this prop prior to porting. Now that it's ported I'm nervous it's gonna turn too many revs. I'm hoping for the one or two rides this weekend, I'll be ok.
seadooaddiction
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Took the boat out yesterday and was able to get on it for the 1st time. The thing has great pull on the bottom and through the rpm range. I was seeing about 7350 rpm but had a miss after the 3/4 throttle position, especially on a nice left hander under load. Kept adding fuel on top to eliminate miss till it started to hesitate and cough. Backed off 1/8 turn from there on the highs. Max rpm was 7390 with the smaller prop. Didn't even bother with a GPS reading. I was expecting 200 rpm higher. It's definitely rich as it climbs the last 70 to 100 rpm. I still had some 100 low lead av gas in the tank from the break in period so my spark plug readings could be skewed but the looked ok at they time. Not sure if I want to lean things out much more just yet.
Sounds like a good day. You got to feel the power without breaking anything. Sounds like you were able to tune it into a safe spot also.
seadooaddiction
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Oh man where to begin with this thing.... Ski has been sitting under a cover since early September. Got my 951 x4 to play with at that point. But heres the quick and dirty: spun the splines out of the prop i was using so i sent it to skat. While at skat, glen and i discussed briefly about pitching it up a a little down the road depending on how things ran. Current directions were to bring back to oem 16/23. A few days later a box from skat showed up stamped 17/24. Against my better judgement i threw it in the pump.... BAD IDEA. Ski absolutely hated it. (Was testing a new porting setup) The motor was popping and breaking up all the way through the rpm band. Was way worse on any turns and couldnt get the macine to run # WOT. Put the ski on the trailer and havent even pulled the plugs. Ran it to fog the motor and winterize it but my guess is it needs a top end, again.
seadooaddiction
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seadooaddiction
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Found that my Coffman pipe has a leak in the water jacket. Im thinking its related to the additional water in the exhaust that shouldn't be there.
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