Just like any other snowmobiler, the thought of turbo charging my sled has lived in my mind from the moment I discovered aftermarket turbo systems. Although my intentions of buying a turbo had to date been more of a pipe dream than anything else, I found myself walking away with a new Silber turbo kit at the Denver Snowmobile Expo last year. The sled I intended on installing this on was my 2017 Ski Doo Summit 850 with 1,600 miles. After a year of running this set up here are my thoughts –
Installation – 4.8 / 5
Silber advertises that this kit can be installed in as little as 3-4 hours which is possible for an experienced technician with the correct tools on a new sled. For most users, plan on a full day especially if your sled has some mileage. Being that I was installing this kit on a sled with mileage not everything came apart as easy as the video shows, more specifically the primary clutch.
Silber includes decent instructions on how to install the kit but the best resource for installation is the video posted by Brandon Cox that goes step by step through the installation. This video is extremely comprehensive and includes all instructions you will need for installation. If you choose to do this yourself, save the headaches and buy the special tools needed to disassemble the clutches. Although it is possible to do it without the clutch tools, it will save a lot of time and headaches when you get to the clutching portion.
The video shows the steps to remove the ECU to have the fuel map reflash completed that comes with the kit. If you are installing in an area that does not have a Silber dealer nearby you will need to remove the ECU and send it to Silber. I am fortune enough to live near several dealers who can reflash the ECU while still on the sled so I was able to skip the steps of removing and reinstalling the ECU.
Installing the turbo assembly, airbox, intake & charge tube, oil lines & coolant lines was extremely easy but did take some time. Being that the sled I installed this on was not brand new, the clutch work was the most difficult portion of the install as it took some effort to get the clutches off and apart.
If I were to buy this kit again, I would likely do the installation myself again since I tend to do my own sled work, and this was a simple install. If you do not want to install the kit, there are a wide range of Silber dealers out there. Some good dealers are Advantage Tuning and Vickery Motorsports that will install the kit for a reasonable price.
Fitment – 4.5 / 5
Fitment of this system is extremely thought out and capable of passing as a factory set up. The turbine, blower, waste gate and all piping come assembled as one unit and fit exactly where the stock can was. The intake tube and charge tube run over top of the engine and take a bit of wiggling through the chassis supports but once in place, look as though they are meant to be. One of the strengths of the Silber system is the utilization of the stock air intake eliminating the need for a snorkel running through your side panel. Although this seems like a minor detail, it is critical in those deep days to eliminate powder bog. Except for the occasional bog on an epic day, I have absolutely no problems with clogged intakes.
The only place that I saw a minor flaw in the fitment is just above the turbo on the plastic vent that is used to cool the stock exhaust. Although not visible from the outside, the turbo will slightly melt the plastic vent enough to smell it while riding the first few times out. A fairly minor detail in my opinion but worthy to note.
Fueling & Clutching – 3.8 / 5
This system is marketed by Silber as tunerless “pull and go” and I would say this is 98% correct. The kit comes with weights for the primary and a chart for what weight and fuel to run at each elevation. Since most of my riding is over 8,000 feet, I choose to stay with 5psi last season in order to only need 91 pump gas.
The kit comes with a 3, 5 and 7psi spring with the ability to run up to 10psi by combining the 3psi & 7psi spring inside the waste gate. I’ve read online that it is possible to do this with the 5 and 7 to achieve 12 but have not tried it since the system isn’t intercooled.
Also included with the kit are new longer bolts for the primary clutch clickers, along with various size weights to put on the longer bolts. Instead of changing ramp angles on the stock clutch, Silber chose to lengthen the clicker bolts to allow room to add weights. This was likely done because it simplifies the install and allows for very quick clutching changes on the snow. Since the Summit comes stock with the clicker system allowing fast changes to the ramp angles, it makes sense that Silber would go with adding weight over changing ramps to simply the install.
Silber gives a chart showing the fuel type to run at each boost level along with the weight to run. When I bought the kit, I was advised by Silber to start at 5psi with my clickers on 3 and set my weights to the elevation I typically ride at. To change to 7psi the steps would be run 2 gallons of 110 mixed with standard 91, bump my clickers up one notch and change the spring.
Now for that 2% tuning that is needed. Since the boost is not controlled by the ECU, you get the same boost no matter the elevation. The clutching is set for a specific elevation / boost which creates a specific amount of horse power. This causes some mildly noticeable lag when getting to higher elevations due to the decrease in horse power being that the boost does not increase with the elevation. This is where the Boondocker Sidekick kit has a leg up. Boondocker uses an adjustable waste gate which allows the boost to increase and decrease with elevation. This equates to the same horsepower being created at all elevations allowing the clutching to be set for a specific amount of horsepower consistently being created. This will eliminates problems with under/overrevving with elevation changes and keep the sled running at peak performance no matter the elevation.
Because of the problem caused by fixed boost, you will need to watch for under/over revving to keep the sled running at top performance. I set my clutching to above 6,000 feet on Silber’s chart and adjust my clickers up or down if I see consistent over or under revving. Silber makes it very clear in their instructions running the 850 ETEC over 8,000 rpms will cause damage to the reeds so it is crucial to watch your rpms with varying snow conditions.
Function & Performance – 3.5 / 5
With close to 30 days on the snow last year I had the opportunity to ride this kit in windshield deep power to rock solid snow. Silber markets this kit as smooth consistent power and with the custom fuel map that Silber developed, I can say it truly is as smooth as they say. There are no flat spots, unusual bogging, or any other strange behavior. The sled runs as good or better then the stock map but with the added fun of boost.
The kit is most noticeable in the deep powder but more specifically it is a game changer if you like riding steep trees. The kit allows you to climb and be more technical with your line. When riding the steep and deep, keeping momentum is everything. This kit adds the horsepower needed to regain momentum after slowing the sled down when going through highly technical areas. As with any kit though, keeping that turbo spooled is key. Throttle modulation while using the brake lever becomes more important and with the custom fuel map that comes with the kit, the throttle response is quick when the turbo is spooled.
Now for the complaints – Although this is minor, when the ECU was reflashed, the altimeter always shows 26,800ft no matter the elevation. I was a bit worried at first that the ECU was fueling the sled incorrectly but the fueling seemed spot on so there must be a disconnect with the gauge output. After a quick talk this year with the Silber crew at the snow show this year, I found that the problem lives in the gauge itself and not in the map and there is not currently a fix for this.
The biggest item I noticed throughout the season on this system is the cooling. Let me start off by saying after close to 30 rides and 900 miles on this kit last season, I did not have a single problem with the sled overheating and never once worried about damaging the sled. One thing I did notice was the overflow tank always seemed to show as low when under pressure.
During the installation, a coolant line is removed from the overflow tank that instead of going directly from the engine to the overflow tank, changes to go through the turbo then to the overflow tank providing cooling for the turbo. Although this is unconfirmed, my theory to the cause of this problem is the heat from the additional fuel being burned and cooling the turbo itself is causing more expansion and contraction of the coolant then a stock sled. This means when running the engine hard, the coolant expands enough to come out the overflow and once it cools down, the system shows as slightly low on coolant.
If this truly is the problem, the simplest fix would be a larger overflow reservoir to allow more room for expansion of the coolant. In defense of the current design, once the overflow occurs once there would be adequate room for the additional expansion and therefore the over flow would not occur again. Being that this solution increases the price of the kit, I can understand how Silber chose to leave the kit as is since it doesn’t cause problems with cooling.
Total Score – 4.1 / 5
For several years I had thought about a turbo kit and the only reason I had to not buy was the price and reliability of the older kits. I can remember rides years ago with people that had the “piggyback” systems that require substantial tuning to get running properly and I felt that for the price paid versus the amount of time tuning simply didn’t pay off.
With the modern kits on the market today that are truly bolt on tunerless kits, the reliability concern I once had is no long there. The Silber kit truly is 100% reliable on new and used sleds, assuming of course the install was done properly, and your sled didn’t have preexisting conditions before install.
With price being the second thing that kept my turbo dreams at bay for several years, this kit also solved that problem. The best part of the kit is that it not only comes with the turbo system itself, it comes with all the clutching you need. When you pay for the kit, there are no additional items you must buy to get the sled performing properly, the price is the price for a pull and go system.
Lastly, value is something that is difficult to measure and lives in the mind of each person when buying a product. I can honestly say, Silber has put a product on the market that measured on a horsepower per dollar basis sets the bar high in the Turbo market.