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Engine Management Tech Progression

Racing drives new tech - In a game of inches, companies are always searching for the next big breakthrough. However, the combination of little things can add up to big gains.
It’s amazing how far snowmobiles have progressed in my generation! I started riding snowmobiles with my parents at age 1 back in the latter half of the 1970s. I remember sitting just in front of my dad on his brand new 440 Exciter. My sister would ride with my mom on her 250 Enticer, going everywhere we would go.

Once I started driving my own, my dad let me ride as much as I wanted, as long as I was the one to fix it. I put on a lot of miles and inherently broke a lot of stuff. Those experiences, along with a bunch of college courses, lead me to my career designing performance parts at Bikeman Performance.
Every day we are pushing technology beyond what the manufactures release. The performance market is a continuously changing field that is a thrill to be part of because we always have to be making leaps forward. The new designs and technology we are designing today will be everybody’s technology tomorrow.

The Progression
Early sled engines were basic, with carburetors, mixed oil and points ignition systems. Carbs were adjustable; usually with a couple screw style needle jets, one covers the low throttle and the other covers the high throttle. Early snowmobile carbs always needed adjustments. The points ignition systems were simple but required maintenance. You would leave on your journey with a pocket full of spark plugs and arrive smelling like fuel if you made it to you destination. Thankfully, those sleds were before I was born, and I am okay with that. The snowmobiles were unreliable, and the real performance was yet to come.

The next generation of sleds (the 70s and 80s) saw great advancements in oil injection, carbs, ignition and tuned pipe technology. With the addition of oil injection there was no more need to carry cans of oil along on your rides or worry if you are mixing at the correct ratio. Carbs advanced with metered jet sizes with charts that made it easy to predict jetting for air density changes. The Ignition systems went away from points, and put out a hotter spark much less prone to fouling. Performance companies sold pipes and other goods and recommended jetting specs. However, many people buying pipes and bigger builds that saw huge performance gains quickly found they were not as reliable as the stock machines. I experienced this generation of sleds first hand.

The 90s was the start of electronic fuel injection (EFI) and carburetors that adjusted automatically. The early EFI systems worked pretty well as long as your battery didn’t die. If it did, you needed to power up the system before it would even pull start. The automatically adjusting carburetors adjusted the pressure in the fuel bowl to richen or lean the fuel mixture to maintain proper jetting as temperature and altitude changed. The EFI systems were not very garage-mechanic friendly for people who wanted to make adjustments. There were chips you could buy that would add fuel flow but usually were not adequate. The automatically adjusting carburetors were much easier to make adjustments for added performance parts but many racers still used conventional carburetors. I was not a fan of EFI at all during this time because of the lack of tune-ability needed for added performance parts.

The new millennium brought on many changes to the world of ignition and fuel control. The manufactures added 3D ignitions, knock sensors, pipe temp sensors, high energy coils and higher tech EFI computers. The new EFI computers were much more precise at calculating the demand for fuel and ignition timing but were not easily adjustable at first. Then came the piggyback fuel controllers. The piggyback or intercept fuel controllers would take the signals going between the Engine Control Unit (ECU) and the fuel injectors and modify it, creating a richer or leaner condition. These fuel controllers opened up the EFI world for the aftermarket allowing them to make endless parts for the fuel injected sleds.

Finally, Dynojet revolutionized snowmobile piggyback fuel controllers by making a controller that used PC software. The Dynojet was so adjustable, I was convinced I could make performance products better tuned on an EFI sled vs. a carbed sled. This was the future. Even though I was familiar with concept and design from the automotive world, I knew I would have to expand my knowledge to stay on top of the advancing EFI technology.
The Bikeman R&D facility continuously tests and evaluates all available performance products, both ours and the competition. The Bikeman Team is proud to say we are constantly researching, learning, and designing new items with the goal to make the best performance products possible.
The Age of high tech EFI
The 4-stroke turbo sleds came in under the radar for many people but it was very exciting for folks like myself. Everything I studied in school was for EFI and by now I knew how to get deep into the binary code allowing us to push 4-strokes into the 400, then 500 and 600hp range, and finally to the 700hp monsters running 60 PSI at over 10,000 rpm. It wasn’t long before drag racing was filled with big 4-stroke turbos. In my opinion, the 4-strokes will continue to dominate the drag and top speed divisions of racing, but for other areas like mountain and aggressive trail riding, I believe the smaller more nimble 2-strokes will hang on.

Soon after the 4-stroke binary was cracked, we were able to get into the 2-stroke binary EFI code. This is the biggest improvement I have ever seen in the 2-stroke performance world. The conditions vary so much day-to-day that the only way to make a snowmobile run consistent is to have access to all of the tables the machine runs on, which we do have for the Polaris CFI and Axys models.

There are over 120 different maps, algorithms and tables that affect what the EFI system does. With a standard piggyback fuel controller you can get the tune right for a given condition but as conditions change you will not be tuned perfect. With our access to the full operating system we can adjust things to make a cold pipe act hot, virtually eliminating cold pipe bogs. This allows us to design our pipes differently to make the EFI system compensate for almost anything. In the last few years we feel we can truly make a modified sled run better and more reliably than a stock sled.

At Bikeman, we sell performance packages with the proper tuning designed for all the components installed. A lot of people ask about an open EFI tuning platform for the sleds to allow consumers to make changes. This is not something I would recommend for our customers because of the amount of time it takes to write a tune. We do it in a controlled environment at a high-tech facility, and the odds of the average consumer making positive changes to a tune is unlikely. Since we have had a closed tune platform our engine failures are no more likely than a stock machine and tech calls are extremely low. The age of high-tech EFI is here to stay and that’s ok with us!

- Joey Strub, Bikeman R&D
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