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Discussion Starter #1
what rpm should my primary engage at? right now its 4600. or is that more of a question for the pipe manufacturer. they are psi modblasters.
 

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Usually with pipes they are around 45-5000 rpm.
 

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The PSI pipes are very weak on the bottom end, most of us that run PSI's hold the engagemant up a lot higher. my 96 with PSI's engages at 54 on the button.
 

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Discussion Starter #4
Ah, bulldog, gald u caught this. i had a buddy ride this ultra, and he says that it feels like it aint shiftin out, doesn't pull hard at all. psi said to go with 54 gram wieghts, currently it has 49. still has the stock helix which i think is 36. psi said go with a 44/32. i have a 45/36 layin around, and plan on puttin 56 wieghts in. this should make it pull alot harder, but isnt going to bring down the engagement rpm?
 

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I also have psi modblasters in my ultra. Mine takes off good, i have 55 gram weights, blue primary spring, and a black secondary spring. I have a 45/36 helix that i am going to try in it when we get enough snow. In grass it will lift the skis about 4 feet high or so.
 

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Discussion Starter #6
sweeeet!!! i meant i am gonna install 54's. but with the current setup my piped xlt will wax it 0-60 while its packin the skiis a foot off the ground. i think my ultra was embarassed [:p]
 

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Try the setup that psi recomends and see if that works. The weights i have are the full tail weights. Mine will hold the skis about a foot off the groud for a ways not sure exactlly how far. At 60 they are still up a little.
 

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you can't just change from a 49 to a 56gram weight without a equal spring change. i agree with psi that 49's are light. i'd put 56's in and then change your primary spring to a EPI red or black. the red is 145/300 and the black is 145/280 so if you try the black and it doesn't pull enough rpm. try the red. come to think of it a 56 might be a tad bit high. can you borrow springs/weights from anybody?? i think a 10A or 10AL is a 55 gram, with a black spring.

as far as the helix goes the 45/36 you have will be fine. i can't remember what spring was in the secondary.

while your at it check and make sure you have 1 1/4" belt deflection.
 

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Discussion Starter #9
i think i will go that way for sure, the ultra goes, don't get me wrong, but doesnt even think about packin the skiis and with a 2" 144 it should have plenty of bite to do so. and iv'e got the suspension soft as snot with the front limiters all the way out. you think that helix will work? this 45/36 is cheaper than new!![8D]
 

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Discussion Starter #10
sorry bulldog, i meant i was gonna go with 54's. so let me see if i get this: the more weight will make it shift and pull harder, but may drop my rpm on both ends, so the bigger spring will help counter that?
 
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