Thread: dissapointing results
05-16-2010, 01:03 PM #1
breezy, light ripples, half a tank ....about as good as it gets
71.5 @ 7850rpm.
It'd spin up to 8150 on the take off...then drop off and slowly climb back to 7800-7850. That's it.
Now, I'd been running a 14/19+1 at 8150 in the heat.....I don't get it. I didn't figure the leading edge would bog down my r's at the top end when it didn't seem to hurt the start.
05-16-2010, 02:34 PM #2
C'mon....30 views and no ideas?
I'll entertain any and all serious thoughts. Please?
Okay...more info....a coupla long leaf pine needles in the pump. Also....this is the first time I've run a nose cone since my oem walked up the shaft on me a coupla years back.
I thought I had it on tight enough....even used blue loctite....it was loose on the impeller.....real loose.
Could it have walked up the shaft then slid back a bit before I pulled it outa the water?.....don't figure so...but?
Would a loose nose cone cost me 150-200rpm?
05-16-2010, 02:37 PM #3
I'm loath to put the tweek on a brand new impeller...but...if I gotta.
05-16-2010, 02:43 PM #4
Dude, I just read this thread of yours and I have no freaking clue what you've done to your ski, what you've changed and what your trying to do. Write up a story of whats happened and what you want to happen so people have a history of what your saying.
To answer one of your questions, yes you change the leading pitch it will make a difference in your rpms up top as well. The two pitches coincide with one another. I think thats what your were asking but I am unsure.
05-16-2010, 03:05 PM #5
my mods are listed in my sig.
I'm trying to run a 15/20 instead of a fully tweeked 14/19.
I experience cavitation for the first time when I had the 14/19 in while running the S3SC.
My thoughts..I'd like to hit 73-74+mph while running a 15/20...even if I'm not quite turning the maximum r's.
Keep in mind....there will be no additional mods done to the ski for the rest of the year...at least...no more go fast goodies...no exIC....no more fuel...ect.
05-16-2010, 03:08 PM #6
another question...I found the pump cone under pressure. Never had it come off so easy. A coupla weeks ago I loaded it with grease....maybe too much?....coulda been putting pressure on the pump bearings?....binding me a little bit?
05-16-2010, 03:42 PM #7
i have loaded my old pump with grease and it didn't slow things down ( i have since changed to a oil bath )is it possible that you have a boost leak ? and how many hours has it been since you had the SC rebuilt ? maybe worth checking the torque on it
05-16-2010, 03:45 PM #8
SC was rebuilt last fall...less than 20hrs...no worries there...I wouldn't think.
boost leak is possible...will check that now.
05-16-2010, 04:27 PM #9
SC to TB hose tightened a 1/4 turn of the screw....enough to cause a leak?
05-16-2010, 04:44 PM #10
the 14/19 should be exactly what you need, especially since you don't have an aftermarket intercooler. check your wear ring which could be why you are hitting limiter on start and going back down. also it's definitely worth looking at the slip on the charger, 20hrs should be time to look again. you must be higher than 9Nm.
you might hit 73-73mph, but only with an aftermarket intercooler and 14/19
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