Arctic Cat can't (or won't) reprogram the 800 ecu's I tried to get them to do it when I converted my '03 800 to a 900. I have one of D&D's pac kits to turn up the fuel pressure then lean the top end down with the restrictor or for that matter
I have a spare '04 900 ecu and a harness modified to put the ecu in the top of the airbox like they are on the '03 800 instead of on the side of the smaller airbox on the '04 900. PM if interested.
Don't risk it!! Get the 900ecu and harness, you will also need the 900 power valve cables to do it right. The issue is timing with the ecu's. Look for a guy on here named Johny Welch, he has posted some great info on this very swap. He's also a great guy to deal with and would be glad to answer any questions you have.
Originally posted by black1010@Sep 28 2005, 07:26 PM This sled is EFI and I talked to both D&D and simons cpr and they said it should not be a problem .
They also said unhook the ethynol wire and it makes it 3% richer
i will assume the timing curve is Ok but the fueling is way different. i remember on the RXL one could bump up fuel pressure to enrichen globally. with a WOT plug check one could calibrate 3/4 to open throttle. that is the easy part. the bottom 1/2 of throttle position is way more difficult. keep in mid EFI is developed by factory after 100's of hours on dyno and also in field. my experience is limited to speed density automotive systems. one can tune a car with a laptop and multiple datalogs. impractical with a sled. carb is the way to go.
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