Questions on Psi Twin Pipes
Hello, I recently got psi twin pipes that came off of an 03 Polaris Liberty 700 (not sure if it was a VES). Now I now that the bolt patterens are different but I mocked them up on an 01 500 VES (useing 2 bolts) and it ran amazingly. My plan is to make my own flange to convert the small block bolt pattern to the big block bolt pattern, while keeping it as short as posible to prevent fitment issues. Does anyone think it would work, and will it need to be rejetted? If so by how much? What was needed to be done for the 700 back then? (Also if your wondering, I didn't buy them for performance, I bought them for the sound, and if I ever get a 700 or 800. It sounds weird but I'm not aloud to have anything above a 500 becuase of my parents, so I'm doing bolt on mods that can be transferred to a higher perfromance sled.). So any and all information and/or help about them would be great. Thanks!
Here's some pictures of them in my sled...
I also have a video of it running if anyone is interested.
Here's some pictures of them in my sled...
I also have a video of it running if anyone is interested.
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Take the pipes off. The sled will run like garbage with them on and you'll spend all winter trying figure out jetting and clutching. I'm all for kids doing work themselves and I applaud your effort but you will deprive yourself of having the ability to ride a really fun sled because you need to put in another set of pistons after yet another jetting "lesson".
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Yeah gotta agree with first two, you will do more harm than good. Now a set from a 600 may not hurt performance much but as stated those 500’s were over achievers.
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Those are center dump pipes so they are a little different animal than the typical twin pipes.Id have to agree that there is a good chance your performance will get worse with those pipes.Those 500s ran really good when they were jetted a little leaner and clutched correctly.(I might still have a hot seat clutch kit for one)
At any rate,if you are hell bent on running around with those pipes you will need to learn how to read spark plugs and piston wash.I would GUESS that you might not even need bigger jets if nobody ever played with the carbs because they were crazy rich from the factory.
I would make a short 300 foot wide open throttle pass and see what the plugs look like.Dont forget that twins are also more difficult to keep tuned for all around riding conditions.
If you are off on the tuning you may also be learning how to rebuild an engine in the near future so Id only do this if you have two sleds.
At any rate,if you are hell bent on running around with those pipes you will need to learn how to read spark plugs and piston wash.I would GUESS that you might not even need bigger jets if nobody ever played with the carbs because they were crazy rich from the factory.
I would make a short 300 foot wide open throttle pass and see what the plugs look like.Dont forget that twins are also more difficult to keep tuned for all around riding conditions.
If you are off on the tuning you may also be learning how to rebuild an engine in the near future so Id only do this if you have two sleds.
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So would you all just recommend selling them and useing the money to buy a can instead? And if so what would you recomend for cans?
As much as I hate the sound of those cans this is a far better option. You will need to do some searches to find a can. I doubt you will find any New Old Stock ones so eBay or Marketplace will be your best bet. Aftermarket cans weren't terribly popular when that sled was new so your options will be limited. Cans became popular when off-trail became popular because off-trail sleds technically do not need to follow the same noise restrictions as trails sleds.
Just ride is for a year as is.
Yep, just put the stock pipe, and can back on or at least find one for an edge 600...it'll run a hell of a lot better than messing with those twins. Only aftermarket can that ran good on those small block liberty 500's that we tested was a dynoport. Most others made the sled louder, and run slower. Real hard to find a better exhaust that the oem one.
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Yeah at least the dynoport wont lose any power as most do.
The cans actually becsme popular when the triple days were coming to an end.Back then everybody wanted triple pipes and when twins came slong guys still wanted to make some noise without the tuning hassles of twin pipes.
The cans actually becsme popular when the triple days were coming to an end.Back then everybody wanted triple pipes and when twins came slong guys still wanted to make some noise without the tuning hassles of twin pipes.
I had a well ported xcr 600 made to run with triple aaen pipes that i eventually setup with the stock 3-1 pipe while using a dynoport can vs the stock one...the sled ran way better at 8500 rpm than it did with the stock can. Yeah, it was a bit louder at idle, but the mid and top end weren't far having the triple pipes back on. Using the stock can was like someone stuffed a potato in the outlet.
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Yeah those older mufflers were pretty restrictive.By the late 90s/early 2000s some were pretty decent.
I cut open an xcr800 muffler and couldnt believe the sled could actually run.
Problem we saw on a later bone stock xlt 600 3-1 exhaust using a dynoport can, it made a tiny bit less hp than with the stock can. Those dynoport cans seem to work very well with ported engines.
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I would vote for the stock exhaust also. There is a lot of math that goes into making a pipe that considers bore and stroke and other factors that are specific to each engine for the pipe to work efficiently, and the pipes you have were not designed around your engine. A can designed for that engine would be a good option but keep in mind that loud exhausts are not always welcome by land owners that the trails use and traverse by and have resulted in loosing access and trails. I cant say what performance gains or loses are but the starting line cans all had just a little more sound but were not offensive. There is added performance just making sure all drive line bearings are spinning with grease in them and a properly tensioned and aligned track. Belt deflection set properly and clutches that are clean without worn out bushings and springs in them also will insure the best performance. As others stated learning how to tune carbs and clutching can result in performance gains for a relatively low cost. Factory jetting is normally set for 20 or 30 below zero and when leaned out for the 20 degree day you will normally ride in your engine will run much crisper and perform better. If you tune for a warm day remember you have to jet back up on the cold days. If you install a Holtzman tempa flow you can jet for -20 deg and it will compensate for the warmer days which improves performance at all temps. I installed at least a half dozen of them on different Polaris sleds and most did not require any tuning beyond air and fuel screw adjustments for the low speed circuits. There was probably room to tune leaner but I was happy with the results. The tempa flow in my opinion is one aftermarket product that truly delivered everything the MFG said it would. Olav Aaen (Aaen performance) has two books out that are very informational one on clutching and one on carb tuning that I have used to learn how these systems work. Awesome to see young blood who are not afraid to wrench on something and try to improve on what the factory designed.
Im curious what it sounds like with center dumps on a small block
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ctr. dump pipes are low rpm pipes. a well tuned 500 xcsp will spin 8400-8500. so absolutely will not work on that sled. period. no jetting etc. going to help. a 500 moves way less air then a 700. stinger outlet dia. lengths of the pipe sections etc. all play a major role here. get rid of them. put the stock ex. one and tune and maintain what you have. P.S.I. pipes are junk.
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Not in all cases...We had the Quickest Open Fuel sled in the midwest back in the early 1990's (660')...The exact same sled set up for NSSR speedruns held the 1320' speed record during the same time period (162mph)...Both had PSI pipes...
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I could be wrong but those dont look like center dumps.
Nvm…..I missed the highlighted remark.
Some of that stuff worked pretty well on race sleds.
Nvm…..I missed the highlighted remark.
Some of that stuff worked pretty well on race sleds.
Yeah, most of the psi pipes our guys used were on race sleds with good fuel....they did well. Back in the day i heard aaens top pipe guy went to work for psi....not sure if true or not.
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The guy your thinking of is Jeff Simons...Olaf taught him everything he knows when he worked for him as a very young kid...I dont remember him working for Bruce @ PSI...He did work for Richerts Yamaha in the early 1990's and built a 6 cylinder V-Max 4 engine...Then he started his own shop SimonsCPR...Not sure what he's doing these days...
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