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i got a polaris indy 440. when i got it it didnt have an airbox so i bought some uni filters with outerwears. what is the stock main jet for the 440? the carbs have 300 mains now. what should i do?
 

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i got a polaris indy 440. when i got it it didnt have an airbox so i bought some uni filters with outerwears. what is the stock main jet for the 440? the carbs have 300 mains now. what should i do?[/b]
Depends on year and model. You can find out what the stock jetting should be here:

http://parts.polarisind.com/Browse/Browse.asp

In the carb section it will tell you what your *stock* main jet should be, which probably applies to your riding conditions. I would check under the hood for a jetting chart just to be sure but make your baseline the stock main jet if you have no other guide. This is assuming your engine and/or exhaust is not modified.

The real question is where to go from there. I'm doing this exact same thing with my 530 LC but I'm still waiting for the exhaust back from the shop. I've asked this question a couple times and I really think nobody has a good answer. When I come up with some testing guidelines I'll report back, but here's my plan:

Change the current jet needle position to the richest.
Change main jet up...but how much? I'm thinking 10%-15%, so from 300 to 330-340 for example. But that is pure conjecture. I think the single exhaust will limit how much extra air is actually added by the pod filters, but on the other hand I could be way too low. Sounds like we both got the "dirt safe" filters which give less flow than the "snow only" filters, that's what I wanted.
Try to tune the air screws with current pilot jet to best throttle response. Start from a quarter turn and test throttle response at each position. I don't know yet if a new pilot jet will be required.

Now you have to remember that when you are tuning you really have to tune in the cold. If you tune it spot-on at 60 degrees, you will be melting down your engine at -10. I assume it's going to take a good sold half day just to get it to where I hope it's safe, and then I will probably be checking it and possibly fine-tuning for weeks. There is the chance that you'll get it right on the first try, but don't count on it.

If you don't know the process for testing the mixture at your different throttle positions, do a google search, there's very detailed articles out there.
 

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filters go up 3 in the mains, depending on the motor 2clips to start with and maybe back to 1 richer, pilots are usually good but some may need 1 size bigger,the air screw goes in....
 

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Discussion Starter #4
i read in my clymers manual that the stock mains were 230. so with my 300 i should be fine? the motor is from a different sled maybe the previous owner had clamp ons.
 
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