Track and Lug Length = Sleepless Nights

[ClutchMaster]

With Yamaha's 2020 snow-check coming to an end in a few days, I need to pick a new sled to get in on their great offerings.
But my questions (shown above), still remain, and the background is the sled will be upgraded with internal engine mods (pistons, rods, cams) and upgraded turbo.
At bottom, what is the best way to put down 350-450 HP to the trail?
Will a 137" be just as effective as a 141 or a 146" track, and if not, would the longer track really be that much worse for trail riding? (I thought my '12 141" handled just fine.)
I'll not use the sled for any type of racing, lake or trail, I just want high HP in the trails for the giggle factor!

What do you think?

What turbo will you be running? Stock ECU?

 

[ktmhk53]

you would need 2 cartsfor that pile of hardware. is the pic when new? or are you actually riding in snow

Yes, that pics was just after the initial studding. Fortunately, it looked exactly the same after almost 200o miles of hard riding

 

[ktmhk53]

What turbo will you be running? Stock ECU?

I'm likely to follow in either Brent68's footsteps (LINK) and have Precision Sport set up a kit with a Xona Rotor 4948 turbo and Motec ecu and tune, OR follow the path Tarzan took (LINK) and go with a MC Xpress kit and BorgWarner EFR 6258 turbo.
A Hypersports setup is another option too, as they have their own ECU for Sidewinders!

Hypersports 998 ECU

All new Hypersports plug & play ECU for the 998 Arctic Cat / Yamaha turbo sleds.

$2275.00 USD plus shipping

NO JUMPER HARNESS! NO WIRING! NO FUSS!

All of the same features and benefits of the record setting Link ECU, in a waterproof, direct plug in unit, that is suitable for race or trail use.

•Mounts in stock location
•Retains OEM gauge and reverse function
•All inputs and outputs are fully configurable
•Bigger injectors? Bigger map sensor? No problem!
•Full datalogging at 100hz with configurable parameters allows you to analyze engine performance and optimize clutching
•Optional plug and play wideband O2 sensor with no wiring required
•Open or closed loop fuel control
•Open or closed loop boost control
•Adjustable knock control
•Powerful built in igniters eliminate the need for add on ignition
•Expansion port for additional inputs and outputs without having to modify harness
•Switch tunes on the fly
•Limited lifetime warranty.
•Access to Hypersports extensive library of tunes

 

[Brent68]

QUOTE="ktmhk53, post: 1485871, member: 5084"]I'm likely to follow in either Brent68's footsteps (LINK) and have Precision Sport set up a kit with a Xona Rotor 4948 turbo and Motec ecu and tune, OR follow the path Tarzan took (LINK) and go with a MC Xpress kit and BorgWarner EFR 6258 turbo.[/QUOTE]
If you decide to go the Motec route, I would suggest a couple adjustments from where I started, especially if it’s going to end up as a snow drag sled.
1. Start with a header rather than stock manifold. I wanted one almost immediately. The bigger turbo spools a tad slower than the stocker....only noticeable on log file but it got to me.
2. There are some really cool cam options. If you’re pulling the motor apart right away for rods, pistons, head studs....add cams with better valve springs. Off snow it’s going to over shoot your target RPM by at least 500rpm. I was constantly dealing with the rev limiter. The big cam options show really nice power gains too.
3. Swain coat the exhaust valves for extra protection. When I pulled mine apart, they showed some stress from heat.
4. In the “would be nice category” is head work. Nice flow gains and looks really cool when putting the motor together .
5. Consider going up one size on injectors on Martin’s standard kit. I run low 80% duty cycle on pump gas on cold days. Not much room to turn it up.

 

[ClutchMaster]

Might I add the viper/nytro cams are substantially larger than the Sidewinder cams, a cheap but effective option if running above 9000rpm.