900-975 Big bore kit pros, con's, concerns - Polaris ATV Forum
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post #1 of 1 (permalink) Old 01-09-2017, 12:21 PM Thread Starter
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900-975 Big bore kit pros, con's, concerns

So after A LOT of headache I finally have my 900xp back together with the 975 kit installed. Aftermarket fuel pump is installed as well as a Dobeck AFR+ controller (which I love). I haven't taken it out on the trail yet as I have a couple issues I'm still working out. If I plug in the controller it idles puuuurfect but if I give it gas it goes WAY lean, like off the gauge lean and dies when I let off. If I take the controller out and just run it in open loop the idles getts crappy but wont die if I give it gas.

Do I need to reprogram the ecu for a diffrent spark curve?
Should I put new injectors on it (has new factory stock now) and if so how big should I go and how big is to big.

This is one of my "lead guide" rigs and I'm not looking for making huge horsepower, I prefer reliability. But ya know, there's no replacement for...

Who else has run one of these kits and what problems or benefits have you seen?
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