AFPR?

The only two that I know about are Vari-Flow and Dial-a-Jet. I installed Vari-Flow this summer, and have used it once this year and loved it. However, I've got carbs, not EFI. Any EFI I've seen don't need either of these devices. I've got Pyros to monitor EGT's. I'd love to install a RacePak, but it all costs money. What range of elevations are you riding at?

The 91 is not smart enough to change for a large range of elevation change. By large I mean that you can not ride in Wisconsin one week, and then climb to the top of Vail Pass (9500 feet) in Colorado the next. Someone that can program the sled will need to program it for high altitude riding. I believe that the cutoff is at 5000 feet. I tried, and it was a dog at 9000 feet, really bad to the point that you could not go down hill without sputtering. But at 900 feet it pulled your arms off.

RXL,

Are you saying that it can adjust itself over a 5000 foot spread. like if you set it up to run at 2000 feet it would run ok up to 7000? Just curious I have one and in WA there is no shortage of mountains...

I need spellcheck!

I think RXL is saying the program was only good up to 5000ft and at 9000ft it was a richdog! But at 900ft it was screamin lean burnin power machine!
With a AFPR you could take out a couple of LBS of fuel pressure and run fine at the higher elevations or add a couple at the lower levels to run with cooler temps! You need EGT gauges so you dont take out to much pressure and run lean! Lean is more powerfull than rich. To lean of a burn causes cilinder/piston melt down!
Most people say it was running awesome then bam! it blew up!

91 polaris indy 650 RXL EFI

You got it correct! If I was led down the correct path, the 91 RXL can be programmed for high elevation > 5000 ft, or low elevation < 5000 ft. Now why they did not make a toggle switch, i'll never know. I do know that there is an aftermarket regulator for cat's efi that will allow you to regulate the pressure. But, I believe that this is only to insure that you are running correct pressure, not as a tuning device. The way that I see it is you have to have everything working in unison to make that triple pig run like a "lean burning power machine." For what it is worth, i'd have your mechanic make the switch. Now, my 500 SP EFI was set up for Colorado's mountains, and I have never switched the EFI module back for flatland riding. She rides really nice without any signs of running lean. It is a 92, so they may have made a change in the EFI - but it's not broken, so I wont fuss with it.

Flange,
Be careful with your vari-flow. I like mine but I burned up my PTO piston last winter.
Dropped down in a hole where it was 20 degrees colder and fowled the plugs with aluminum (Not good!)

MnMark, I think black magic has one for the cats you might call and ask them.

Member #2 of the Arctic Cat Mind Control Team

I hear ya 2000TCMC! I'm pretty paranoid with it right now. I watch the EGT's pretty close. I've also got a keychain thermometer that I keep an eye on. I hope to make this a habit!