SLP Intake & Exhaust for Polaris RMK 800

We’ve been accused of using a lot of stuff from Starting Line Products, and we do. History has shown us that exhaust systems from SLP work as advertised, and do so across a wide range of conditions. So when it came time (after the one year warranty had expired) to juice-up the performance on our 2003 Polaris RMK 800, we turned to Starting Line for their complete intake and exhaust systems to make our RMK run with the more powerful mountain sleds.
We took our stock RMK 800 and installed the SLP single pipe exhaust and silencer, a set of #65 Boyesen RAD valves, the SLP airhorn kit, and mounted two of the round intake valves in the dash. Clutching was enhanced per SLP recommendations, with the addition of SLP MTX flyweights and a TEAM rapid Reaction roller secondary, all set-up according to the enclosed SLP spec sheet, running at 8000 RPM. SLP does an excellent job at providing stock-like grids with exact jetting and clutching specs for all elevations and temperatures, and they’re on the money. Our carb set-up only required changes to the mains and needle positions, and slight tweaks to the airscrew, with no changes to the pilots, needles themselves, needle jets, or slide cutaway, all per the SLP spec chart for our exact combination.
As expected, when the sled was unloaded in Island Park, Idaho it performed flawlessly. Jetting was right on, clutching was right on, everything was right on. Peak power was much stronger, midrange was snappy, the entire sled performed better in every type of riding.
What did we lose? Other than a bunch of weight, not much. Maybe the money it takes to make these improvements, but the end result is a proven performance package that eliminates the guesswork as to how to set it up and get it calibrated. The exhaust does add some noise, as does the airhorn and Flow-Rites, but the large volume canister silencer does a far better job at silencing that old-style glasspack silencers. We believe it is right there on the edge of acceptable if you’re under scrutiny, nothing like pipes of only a few years ago.
Weight savings amounted to 4.25 pounds less with the silencer (8.75 vs. 13) and 5.75 pounds on the expansion chamber and Y-pipe (8.75 vs. 14.5) for a total weight loss of 10 pounds.

Power gains are most impressive with this package; most 800 VES engines come in at about 138 HP, and we saw nearly 15 HP gain; the Y-pipe and expansion chamber is good for around 10 HP, and the airhorn kit and Flow-Rites add almost 3 HP, with a couple more from the reeds, so we’re up over 150 HP to 152-153, good enough to run with those pesky 900 Cats that wail out 152-153 when stock! If you want to run with a King Cat, this is what it takes!
All of these individual components can be added separately, or in most any combination, but we followed the suggested combinations supplied by SLP. Our only deviation from their specs were the RAD valves, which integrated into their package flawlessly. Some riders may choose to install the dash intakes and exhaust without the airhorn kit, some may only install the exhaust and some may do their own combo. We believe it to be very important to yield to the expertise of the SLP staff and utilize their specification charts, as they have done extensive testing on the listed packages and make those suggestions based on their field results. We have spent countless hours in the field testing with them and observing their procedures, and are confident in their process. This is why we can recommend their packages with such confidence. We’ve seen first hand how they do it and have followed their set-ups times after time with great results every time.

Time to tally up the damage. The Ceramic-coated single pipe and silencer with black Y-pipe runs $494. Two Flow Rites go for $17.95 each, that’s $35.90 total. High Flow Airhorn Kit adds another $39.95. The Boyesen RAD Valves were $268.75 (SLP suggests V-Force3 reed valves at $258 a set, we know both work well). The MTX flyweights go for $99.95 for the set. The complete package amounts to $938.55. Add to that the TEAM Rapid Reaction Roller Secondary and we’ve got another $350, so we’re up to $1288.55. There’s little guesswork here, it’s all proven, and it works. This is what it takes to run with the 900s, and it’ll still have a wide tolerance band that doesn’t need constant tweaking.
Starting Line Products has a host of dealers across the west who can hook you up with a package like this or one similar to match your needs and budget, or you can also contact SLP for your nearest dealer or work with them directly as they have a competent staff and excellent technical support that is the envy of the aftermarket. Call them at 208-529-0244 or visit startinglineproducts.com