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Discussion Starter #1
ok, so i got a set of pipes off ebay for my sled. they are SLP's but im not sure if they are low or high RPM. i was thining of just using a 42/34 helis with an EPI white secondary, polaris blue primary with 10A weights. what do you all think??
 

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Are there any #'s stamped on them. I would get slp's recomndation and then go from there. There clutching is spot on but their jetting way off.

On my stock ultra I was running a 45/36 polaris helix. I think you may need more ramp than the 42/36.
 

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Discussion Starter #3
45/36?? was it a single pipe ultra? that seems like a steep angle. i havent got the pipes yet. they're in the mail. ill let you know when i get them.
 

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Yes it was. Stock helix was a 36.
 

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Discussion Starter #5
hmmmm. well my machine only pulls hard to about 70. after that, its sort of a slow climb. i want it to pull hard to 85 or so. im thinking a different helix and differetn weight profile. what do you think?
 

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I don't really know since you have the pipes, contact skipanator. He has done lots of work with the piped 680's.
 

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Discussion Starter #7
well i got the pipes in today. SLP reccomends i use 30's for pilot jets, 247-P-4 needle jets and they reccomend their own needle that doesnt exist anymore. i just dont know what i have stock in my sled right now so i dont know if i can get by with just changing out the mains. does anyone know what all the stock jetting is in a 1996 ultra SKS?

thanks.
 

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Originally posted by indy_guy
[br]well i got the pipes in today. SLP reccomends i use 30's for pilot jets, 247-P-4 needle jets and they reccomend their own needle that doesnt exist anymore. i just dont know what i have stock in my sled right now so i dont know if i can get by with just changing out the mains. does anyone know what all the stock jetting is in a 1996 ultra SKS?

thanks.
Stock needles and Q-2 or Q-4 needle jets. (247)
 

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Discussion Starter #9
SLp tells me to use the stock 247 P-4 needle jets. why change them?
 

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Originally posted by indy_guy
[br]SLp tells me to use the stock 247 P-4 needle jets. why change them?
SLP made special needles to work with stock P-4's. If you don't use them, you can't use stock P-4's. Too small. You'll run too lean in midrange and melt pistons. Using stock needles changes other settings as well. Your better off letting a pro set it up for you.
 

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Discussion Starter #11
i heard the needles were used to clean up the RICH spot in mid range. the Q-4's sort of seem too big. i dont want ot lean out but i dont want to find that im too rich either.
 

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That's the range I was given to start with. Now running Q-2's for two years with stock needles in a friends ultra w/SLP's. @8200 rpm. My ultra is setup for Aaen high RPM pipes with a slightly different carb setup. Mine is running stock pilots and a different needle position. @9200rpm. Maybe compare to a '97 SPX setup. My XLT w/Ultra SPX motor was a whole different setup.
 

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I just set my brothers 97 ultra up with SLP pipes yesterday. Use SLPs clutching, 30 pilot jets, try and find some of SLPs needles and use #4. Put 380-390 mains in and hang on! Should run around 8600RPM
 

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Hey indy guy, I am having a few sets of needles made per SLP's print. I may have one set sold already and I should have another set to sell, If you are interested, let me know. The SLP needles are quite a bit different than the stock ones and should be used to get it set up RIGHT. Different needle jets can be used, but will not be optimal. I also reccomend you go to SLP's website and download the manual for your pipes, there is quite a bit of important information in the manual such as a required timing change.

I have also read that the pipe stamped "SLP" can be measured to determine if the pipes are the high or low RPM versions. I think 9" down the fat part of this pipe is low RPM and 8" in the same location is the high RPM version. I am going to call SLP to verify this though.
 
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