2002 polaris 800 xc sp
Amsnow
W hen we test rode the 2002 800 XC SP, we noticed an improved performance feel in the new 800 VES engine. It was a bit snappier and felt a little stronger. We had no inkling of how much stronger the engine would prove to be on the dyno. The ol' seat of the pants kinda let us down on this sled.
Polaris made a number of improvements to the engine this season, to not only boost output, but also to make it a friendlier unit to own.
The addition of new variable exhaust valves is the most blatant of these improvements. But the engineering department addressed a major concern from the previous year's version and added a decompression system to the cylinder to lighten the effort needed to pull the engine over. A small vent hole is cast in the cylinder from the interior wall of the piston, through the water jacket and out the VES housing. "As we were redesigning the cylinder our engineering team designed a way to reduce the compression at startup, but keep the compression when the engine is running," explained Polaris' Bow Crosby. "When the engine is not running the VES slide leaves the hole open. But as the engine speed increases and cylinder pressure builds, the valve slides up and effectively closes the decompression hole. It's the best of both worlds." Our test crew heartily agreed.
Other changes to the engine package include a new crankshaft design and lighter weight pistons. All in an effort to make the mill more efficient and durable.
Our dyno test sled was one of the first units to hit the east coast in the early fall. It showed us a tremendous gain over last year's 129 horsepower. While Polaris only claims a four-percent bump in output on the top end, our test unit delivered an astounding 140 ponies at 7700 rpm. That doubles the factory estimates at an eight percent bump.
"We had to work a little to find that kind of power from the engine," noted our dyno tester, Rich Daly from Dynoport. "We dropped a ton of jet sizes to get there. This unit was jetted very conservatively out of the crate. We pulled about four or five horses stronger at peak jetting over stock. But guys should be careful when they do jet down."
We didn't notice that kind of performance in our test rides last spring, but that's just part of riding prototype and preproduction units. Sometimes they change. This time it is for the very good.
Special thanks to Ingles Performance in Phoenix, New York (315/598-7422) for providing our test unit on such short notice!