best performance kit

[tdbaugha]

OEM Pistons

This is what Curt had to say:

"Hi Tory, since the 800 dragon first showed up in 2008 the cfi 800 has had the same issue and we have stuck with the same program to correct it. IMO you can't beat a Elko OEM piston, we correct the bore size if clearances are to loose (this has slowly gotten better from Polaris over the years) by re nicasiling the cylinders to our spec and stick with the oem piston. Excessive skirt clearance is the cause of the piston/cylinder skirt failures experienced over the years on the cfi 800.

Long story short, we tell our customers that no matter what they do, that cylinder won't safely run ANY piston beyond 2000 miles without risking skirt failure-any model, any year. We get them on a program to measure clearance at 1500-2000 miles and drop in a new set of pistons if needed. I can honestly say we have never had a skirt failure with that program.

Installing the "13 cylinder will add durability to your engine, check the clearances with new stock pistons and they need to be .0055-.006" max. Correct the bore if they exceed .006".
A real port job with a good pipe and head and that engine will make 170hp trouble free and typically need pistons replaced every other year assuming average mileage per year for a mountain sled.

Hope that helps!

Curt"

 

[RKT]

This is what Curt had to say:

"Hi Tory, since the 800 dragon first showed up in 2008 the cfi 800 has had the same issue and we have stuck with the same program to correct it. IMO you can't beat a Elko OEM piston, we correct the bore size if clearances are to loose (this has slowly gotten better from Polaris over the years) by re nicasiling the cylinders to our spec and stick with the oem piston. Excessive skirt clearance is the cause of the piston/cylinder skirt failures experienced over the years on the cfi 800.

Long story short, we tell our customers that no matter what they do, that cylinder won't safely run ANY piston beyond 2000 miles without risking skirt failure-any model, any year. We get them on a program to measure clearance at 1500-2000 miles and drop in a new set of pistons if needed. I can honestly say we have never had a skirt failure with that program.

Installing the "13 cylinder will add durability to your engine, check the clearances with new stock pistons and they need to be .0055-.006" max. Correct the bore if they exceed .006".
A real port job with a good pipe and head and that engine will make 170hp trouble free and typically need pistons replaced every other year assuming average mileage per year for a mountain sled.

Hope that helps!

Curt"

That is some decent advice...Curt is a knowledgeable person for sure.

Elko is a decent piston...but Polaris has not used the Elko piston since 2010.. None of the Pros are fitted with the Elko Piston.

The OEM pistons, when new out of the box, come in at .005"-.0065" clearance.. The issue is that they do not stay at that clearance very long at all..>>Most, immediately, begin skirt collapse and at as little as 200 miles could be at .009" or larger and they continue to collapse (this is also the problem with any Wiseco piston made today).

So, replating the cylinder may buy you a little time but with a piston that is continually "shrinking", you soon find yourself out of spec regardless of what you plate the cylinder at.

 

[4Z]

This is what Curt had to say:

" I can honestly say we have never had a skirt failure with that program.
Curt"

That right there is powerful.

 

[rmscustom]

All I know is that my 13 the first few hundred miles had great power but after that it seems to have gotten progressively more tired. 1300+ miles, oiler turned up to 32:1 from day one... Its gonna get some help this fall

 

[TARI]

I use a Japanese piston for our kits, which I feel is the best piston.
Some use Chinese pistons, which I wont use but some on here some feel these are the best. Problem is people that don't build engines everyday, really don't know, but are on the sites giving false information, which is bad for others reading. Some of the issues with the polaris piston is not just in the base of the piston skirt measurement, being .0055-.006" clearance. but in other areas.
Ted, Terra Alps

 

[tinkerjohnson]

Here's what it is in a nut shell!! IMO I believe that all the kits available on the market work, and work well for each person. But for any of these kits to preform at all you must have the clutching right for your sled riding style and elevation. With out that you can take the best running sled with the most HP and screw up the clutching and a stock 440 will run all over it.. So if your on a limit to what you want to spend on "said" kit make sure you spend the cash to clutch it right or the rest of the purchase will be a waste.

Bingo