2001 polaris 800 twin
Amsnow
Polaris was the first to the modern market with an 800cc twin with its 2000 800 RMK. The sled roared, women swooned and Polaris looked like the king. This year, the 800 Polaris mill, whether in the XC SP, LE or RMK packages, will have competition.
For 2001, Polaris engineering has made some changes to its big twin. "We've bumped up the compression," commented Snowmobile Product Manager Bow Crosby. "We have also remapped the ignition timing and incorporated a lighter piston." All three changes have combined to offer better throttle response and it boosted the low end output on the big twin.
Similar to last year, the big twin will be fed by a pair of 40mm flat slide carbs with throttle position sensor and a fuel quality ignition switch.
"You can see the improvements the higher compression head creates at the low end," said our Dynoman Rich Daly, of Dynoport. "There's an increase in horsepower and torque all the way through the powerband, but it is most noticeable in the low and mid rpm ranges."
Daly also noted that the increased compression will be a bigger factor at higher elevations in the RMK packages.
The Polaris mill, unlike the Arctic Cat 800 twin, is a punched out 700 big block engine. If you do the math on the increase from 700 to 800, it comes out to a 14.29 percent volume gain. When you apply that percentage to the 700 engine's output of 112 hp at last year's Shoot-Out, you get 128 hp. Our dyno test sled actually produced 129.9 horsepower.
Like its predecessor, the 2001 engine offers tuners a long, broad power curve to shoot at. It maintains its 88 foot/pounds of torque peak for a huge 700 rpm range. It stays at or above 128 hp for 500 rpm, from 7700 to 8100. Polaris officials have indicated that this is slightly down from where their factory testing rated the engine. In keeping with Polaris official policy, however, they declined to offer a specific horsepower figure.
In our October issue, we reported that the 800 XC SP pulled ahead of its classmates and held them off for a half mile. We stand by that report. But after some serious re-engineering in the Arctic Cat and Ski-Doo plants, the competition looks to have made significant gains in engine performance. We'll have all three brands' full-production units on the dyno at this year's American Snowmobiler Shoot-Out. You can find the event's results in the Shoot-Out section of our Web site. The full reults will also be in our Spring, 2001 issue.