STAIN
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- 2024 Arctic Cat Riot 9000
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Those vents in the knee area are a no go for me.
I get that...I thought they would be an issue as well but I have had them on my SW for 5++ years and they have withstood the knee pressure they take very well. I also think they vent the most heat. It depends on how much structure you leave under the vents when drilling the panels.
mrtwostroke
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- Sidewinder MTX 240 Tune Sidewinder XTX 240 Tune MountainMax SL 153.
Yamaha Sidewinder Belly Pan Vents
All of our custom snowmobile vents come with a indestructible pvc coated mesh that is bonded to the frames. Our side vents come with a special layer of pre-filter material that will help protect your clutches from any moisture.
www.moflowvents.com
Last edited:
baggs66
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- 06 apex gt
I used frog skins and made my own venting, cheap and have large selection of size and shapes to put where ever you like, have used on multiple sleds with great results.
number1kyster
TY 4 Stroke God
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IMO, it isn’t really an issue. I have a long groomed forest road behind my house. My SW literally had dozens of long WFO, 124GPS pulls in the time I had the sled. 0 muffler issues, no melted plastic, just a boot that seperated at the seam.
I know the gentleman that purchased my sled. It is at almost 10k miles now, 9,000 with the SM tune.
Turboflash
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- '17 ZR9000 Ltd. 137 - PEFI Stage 4
IMO, venting certainly doesn't hurt at any performance level.
That said, most important issue to allow a 998 to live at wfo is managing IAT, engine oil temp, and coolant temp. Oil temp being easiest to manage since good synthetic oils can easily live healthily at 275+ degF.
IAT affects charge density which affects how much timing and boost can be run safely. High IAT means much greater chance of deto. Biggest challenge or limiting factor is coolant temp.
The stock cooling system in this chassis is not able to shed enough BTUs to keep engine at thermostat temp at wfo. Not only is the total volume of coolant in the entire system inadequate, but specifically, the volume of coolant in the head is just too small to cool the head enough to be able to run wfo a long distance (1 mile+) without saturating and overheating. The coolant passages in the head are too small, and there is not enough aluminum in contact with coolant to absorb enough btus to cool the head at wfo. And, there is not enough heat exchanger volume to cool the coolant back down to thermostat temp prior to it re-entering the head. Just watch your coolant temp on your cluster as you run wfo, or back-to-back-to back wfo runs, or try to run long distance wfo. At wfo, the temp starts a continuous upward climb. Remember, the temp you see on your cluster is coolant temp coming into head from heat exchangers, not temp of coolant leaving the head. If you're seeing 190-200+ on cluster, the coolant temp leaving head is more like 225-235+!! This will lead to detonation, heat soak, and probably piston damage.
That said, most important issue to allow a 998 to live at wfo is managing IAT, engine oil temp, and coolant temp. Oil temp being easiest to manage since good synthetic oils can easily live healthily at 275+ degF.
IAT affects charge density which affects how much timing and boost can be run safely. High IAT means much greater chance of deto. Biggest challenge or limiting factor is coolant temp.
The stock cooling system in this chassis is not able to shed enough BTUs to keep engine at thermostat temp at wfo. Not only is the total volume of coolant in the entire system inadequate, but specifically, the volume of coolant in the head is just too small to cool the head enough to be able to run wfo a long distance (1 mile+) without saturating and overheating. The coolant passages in the head are too small, and there is not enough aluminum in contact with coolant to absorb enough btus to cool the head at wfo. And, there is not enough heat exchanger volume to cool the coolant back down to thermostat temp prior to it re-entering the head. Just watch your coolant temp on your cluster as you run wfo, or back-to-back-to back wfo runs, or try to run long distance wfo. At wfo, the temp starts a continuous upward climb. Remember, the temp you see on your cluster is coolant temp coming into head from heat exchangers, not temp of coolant leaving the head. If you're seeing 190-200+ on cluster, the coolant temp leaving head is more like 225-235+!! This will lead to detonation, heat soak, and probably piston damage.
